Majority Of Pts Research Articles

LABORATORY PROFILE OF INDOOR PATIENTS ADMITTED WITH ACUTE ENCEPHALITIC SYNDROME IN A TERTIARY CARE CENTRE OF NORTH-BENGAL

Background: Acute encephalitis syndrome (AES) is dened as the acute-onset of fever and a change in mental status (including signs and symptoms such as confusion, disorientation, delirium or coma) and/or new-onset of seizures (excluding simple febrile seizures) in a person of any age at any time of the year. Most AES is considered to be due to a viral-encephalitis, virus like West Nile, Herpes simplex virus, Flaviviruse like JE and dengue are more prevalent in South East Asia. Methods: This observational Cross sectional Study was conducted in the indoor patients of Department of Medicine at Tertiary care Hospital in North Bengal from May 2013 to April 2014. All consecutive patients of AES admitted during this period were included in the study. The study region covers the various districts of North Bengal. Template was generated in MS excel sheet and analysis was done on SPSS 20.0 software. Results: Among 104 acute encephalitis syndrome patients, 68 (65.38%) were male and 36 (34.62%) were female. The majority of pts (54.81%) were >40yrs of age. The lowest wbc count was 3000/cumm and highest was 21,200/cumm with mean wbc count being 10462.56±3567.832/cumm. Asignicant number 56 (53.85%) of patients had serum potassium levels between 2.5-3.5meq/dl. The no. of JE Positive patients was 75 (72.12%) which may be due to the local endemicity of the disease Conclusions: Majority of cases were in the age-group of more than 40 years, with male predominance. The no. of JE Positive patients was 75 (72.12%) which may be due to the local endemicity of the disease.

Radiomic features of renal cell carcinoma primary and metastatic sites as predictors of TERT and BAP1 mutations.

282 Background: TERT and BAP1 mutations are associated with poor clinical outcome in patients (pts) with metastatic renal cell carcinoma (mRCC) (Dizman et al JITC 2020; Joseph et al J Urol 2016). In this study we explore radiogenomics as a non-invasive method to identify these alterations. Methods: Pts with mRCC who had genomic testing in the course of routine clinical care were included in the current analysis. Pts were assessed with the GEM Extra assay, a CAP-accredited, CLIA-certified test encompassing paired tumor-normal whole exome sequencing (WES) and tumor whole transcriptome sequencing (TGen; Phoenix, AZ). Pts underwent CT imaging; radiomic analysis was performed on the segmented metastatic and primary lesions. Features were independently correlated with TERT and BAP1 mutation status to generate Pearson correlation values (PCVs). Results: 92 pts (65:27 M: F) were included in the analysis; of these, the majority of pts (84%) had clear cell histology. Alterations in the TERT gene were seen in 12 pts. In these pts 1,325 radiomic features of the primary tissue were examined and 251 features correlated with a PCV ≥ |0.2|. Of these, 42 features were correlated with a PCV ≥ |0.3|. Highest correlation with TERT mutation was seen with Gray Level Cooccurrence Matrix (GLCM) and First Order Features (FOF). 9 pts had BAP1 mutation with 5 detected in primary tumor and 4 in metastatic sites. Analysis of primary tumor imaging yielded no significant associations between radiomic features and BAP1 mutation. However, out of approximately 1,500 radiomic features noted in metastatic sites, 111 features correlated with BAP1 mutation with a PCV ≥ 0.2. Of these, 15 features correlated with a PCV ≥ 0.3. The radiomic features with the highest correlation with BAP1mt were Gray Level Dependence Matrix (GLDM) and GLCM. Conclusions: By identifying a correlation between radiomic features of TERT mutation in primary tumors and BAP1 mutation in metastatic sites, our work may ultimately yield a non-invasive method of discerning mutational status in patents with mRCC. Efforts are ongoing to validate our findings within The Cancer Imaging Archive.

SGNTUC-019: Phase II basket study of tucatinib (TUC) and trastuzumab (Tras) in previously treated solid tumors with HER2 alterations: Urothelial cancer cohort (trial in progress).

TPS499 Background: Tucatinib (TUC), a highly selective HER2-directed TKI recently approved for HER2 overexpressed/amplified (HER2+) metastatic breast cancer, is being developed as a novel therapy for patients (pts) with metastatic CRC, gastric cancer, and other GI tumors. In xenograft models of HER2+ and HER2-mutated (HER2-mut) tumors, dual targeting of HER2 with TUC and trastuzumab (Tras) showed superior activity to either agent alone. Despite the development of several new therapies for metastatic urothelial cancer, response durations generally remain short and the great majority of pts succumb to the disease, highlighting the need for therapeutic approaches. Given that 20-30% of urothelial cancers have molecular alterations of the ErbB family, TUC in combination with Tras warrants further evaluation in this population. The SGNTUC-019 basket study is evaluating TUC in combination with Tras in pts with HER2+ or HER2-mut solid tumors, including a cohort of pts with locally advanced or metastatic (LAUM) urothelial cancer. Methods: SGNTUC-019 (NCT04579380) is a multi-cohort, open-label, international phase II study evaluating pts with previously treated solid tumors displaying HER2 overexpression/amplification or activating mutations. Eligible pts must have HER2+ or HER2-mut LAUM solid tumors, with progression on or after the last systemic therapy for advanced disease. Pts must be ≥18 years old, with ECOG PS ≤1, adequate hepatic, hematological, renal, coagulatory, and cardiac function, and no prior exposure to HER2-directed therapy. For eligibility, HER2 alterations can be demonstrated by HER2 overexpression/amplification in tumor tissue by prior IHC/ISH (IHC 3+/signal ratio ≥2.0 or gene copy number >6), or by HER2 amplification/mutation in a prior or on-study NGS assay of ctDNA or prior tissue NGS assay. The HER2 overexpression/amplification urothelial cancer cohort will enroll 12 RECIST 1.1 response-evaluable pts. If ≥2 responses are observed, the cohort will be expanded to a total of 30 pts. Pts with HER2-mut urothelial cancer will be enrolled in a cohort of 30 pts for all solid tumor types except breast cancer and non-squamous NSCLC. If justified, a separate cohort for HER2-mut urothelial cancer may be opened. The primary objective is antitumor activity in each cohort, with confirmed ORR as primary endpoint, and disease control rate, duration of response, PFS, and OS as secondary endpoints. Pts will receive TUC 300 mg orally twice daily and Tras 8 mg/kg IV on Cycle 1 Day 1 and 6 mg/kg q21 days from Cycle 2 Day 1. Disease assessments per RECIST 1.1 will occur q6 weeks for 24 weeks, then q12 weeks. Trough concentrations of TUC will be evaluated in all pts in Cycles 2-6, with a peak concentration sampled in Cycle 3. Quality of life will be evaluated q2 cycle using EQ-5D-5L. Sites will open in the US, EU, and Asia; enrollment is anticipated to begin in Dec 2020. Clinical trial information: NCT04579380.

First assessment of the stool mycobiome in patients (pts) with metastatic renal cell carcinoma (mRCC) receiving targeted therapy (TT) or immunotherapy (IO).

337 Background: Previous studies have associated specific stool bacterial species with response to both targeted therapy and immunotherapy (Routy et al Science 2018; Dizman et al Cancer Med 2020). Abundant fungal elements also constitute the human microbiome (the so-called “mycobiome”); we explore whether these could be related to clinical benefit (CB) from TT. Methods: Pts from 2 simultaneously conducted studies were included in the analysis. Both studies enrolled patients with histologically confirmed RCC with metastatic disease; in one study, pts received standard of care (SOC) TT, while in the other pts received SOC IO. In both studies, stool was collected at baseline and at multiple timepoints thereafter. Whole metagenome sequencing was performed for fungal microbiome composition (TGen North, AZ). Linear discriminant analysis (LDA) effect size (LEfSe) was used for comparison of the gut mycobiome in patients who obtained clinical benefit (CB; complete response, partial response or stable disease > 6mos) versus no clinical benefit (NCB; progressive disease or stable disease ≤6mos) from TT or IO. Results: A total of 50 samples from 24 pts (19:5 M:F) were included in the analysis. The majority of pts (19; 79%) had clear cell histology. 15 pts received TT while 9 pts received IO. The fungal genera demonstrating the highest abundance was Saccharomyces with a median relative abundance of 86.9% (range, 11%-99%). LEfSe performed in different taxonomic levels revealed Malassezia globosa (LDA = 4.93; P = 0.038) and Alternaria infectoria (LDA 4.94; P = 0.018) as gut mycobiome components associated with NCB, and order Russulales associated with CB from TT (LDA = 4.93; P = 0.018). In contrast, no association was identified between mycobiome profile and CB in the IO-treated group. The presence of several pathogenic fungi such as Candida albicans and Aspergillus fumigatus was noted in a minority of pts and did not have any bearing on clinical outcome. In pts with serial samples, a trend towards decreasing Saccharomyces spp. (the most abundant species) and increasing fungal diversity was noted. Conclusions: Our study is the first to highlight potential associations between the mycobiome and CB with TT. Our finding of Malassezia spp resulting in lack of CB with TT bolsters findings from Aykut et al (Nature 2019), implicating the same genera in progression of pancreatic cancer. Confirmation of these findings in larger series is underway.

Efficacy of enfortumab vedotin in advanced urothelial cancer: Retrospective analysis of the Urothelial Cancer Network to Investigate Therapeutic Experiences (UNITE) Study.

443 Background: Enfortumab vedotin (EV) is an antibody-drug conjugate targeting Nectin-4, which is FDA approved for patients (pts) with treatment-refractory advanced urothelial cancer (aUC). The activity of EV in pt subsets of interest such as those with distinct histological variants has not been well defined. Methods: A retrospective study of pts with aUC treated with ≥1 dose of EV as standard of care (SOC) or on a clinical trial (if trial results already reported) at 12 US sites was undertaken. Objective response rate (ORR) was investigator-assessed for pts with at least one post-baseline scan or clear evidence of clinical progression. ORR was compared across subsets of interest using proportion test. Results: A total of 184 patients with aUC were included; median age at diagnosis 70, 20% women and 60% with definitive surgery. Most common primary sites included bladder (70%) and upper tract (28%). Majority of pts (72%) had pure urothelial histology (UH) per local review, but 26% had at least a component of variant histology (VH), most commonly squamous (14%), micropapillary (8%) or plasmacytoid (3%). EV was given as monotherapy in 84% and as SOC in 58%; and 81% had ≥ 1 prior treatment in the metastatic (met) setting. ECOG PS was ≥2 in 15%; 37% had baseline neuropathy, 15% diabetes and 9% had GFR≤30. At median follow-up of 37.0 (IQR: 20.5-60.2) months from initial diagnosis, median time from met diagnosis to EV start was 11.7 (IQR: 4.3 – 20.5) months. Median duration of EV was 5.5 (IQR: 1.4 – 6.7) months, and 84% of pts were evaluable for response. ORR for evaluable pts was 53% (8% CR, 45% PR); 25% had SD and 21% PD. Median PFS and OS were not yet reached. At data cutoff in 9/2020, 55% had stopped EV (36% due to PD, 19% intolerance) and 65% were alive. Comparison of ORR in subgroups of interest for 127 evaluable pts treated with EV monotherapy is shown in the table below. Notably, among 31 pts with FGFR3 alterations, 26 were evaluable and ORR was 46%. Conclusions: In a large, retrospective, multi-institutional cohort, responses to EV were observed across a broad range of aUC pts, including pts with variant histology component, FGFR3 alterations and also in populations previously excluded from clinical trials such as pts with GFR<30 and significant baseline comorbidities. No significant differences in ORR were demonstrated for patient subsets of interest. [Table: see text]

Absolute eosinophil count as predictive biomarker of irAEs in patients with metastatic renal cell carcinoma (mRCC) treated with immune checkpoint inhibitors (ICIs).

345 Background: Nivolumab and ipilimumab are associated with immune-related adverse events (irAEs) and, to date, few biomarkers predictive of ICIs toxicity are reported in mRCC. Methods: We conducted a single-center, observational, retrospective study at Clinical Oncology Unit, Careggi University Hospital, Florence, Italy. We evaluated 43 patients (pts) with mRCC treated with ICIs from April 2013 to May 2020. Absolute Eosinophil Counts (AEC, N°/μL) were registered at baseline and at time of occurrence of irAEs. This study aims to evaluate whether the AEC could be a predictive biomarker of irAEs in patients with mRCC treated with ICIs. Results: Median age was 65 years and males were 81.4%. 10 pts received Nivolumab+Ipilimumab, while 33 pts received Nivolumab single agent. 74.4% pts (32/43) developed at least 1 irAE, 11.6% with G3-G4 irAEs. The most frequent first irAE was endocrine event (40.6% pts; 37.5% with hypo-/hyper-thyroidism). The baseline mean AEC was 163.1/μL in our cohort, in particular 132.2/μL in pts who did not develop irAEs and 176.7/μL in pts who developed irAEs (p=0.134). Among the pts who developed irAEs, the mean AEC was lower in pts with G1-G2 (153.1/μL) than in those with G3-G4 (330/μL; p=0.0013) irAEs. At the time of onset of the first irAE, the mean AEC increased to 247/μL (Δ 140.1%). Analyzing the trend of AEC from baseline to time of occurrence of irAE for the 32 pts who had developed at least one irAE, 53.1% (17 pts) showed an increasing trend; among these pts, the most frequent irAEs were endocrine occurring in 4/17 pts (23.6%). An increasing trend was also observed in the majority of pts who developed G1-2 (14/27, 51.9%) and G3-4 (3/5, 60.0%) irAEs. Additional analyzes are ongoing to identify appropriate cut-offs of AEC to better stratify patients. Conclusions: There is little evidence in the literature about the potential role of absolute eosinophil counts as a predictive biomarker of irAEs in patients with solid tumors treated with ICIs, and most refer to patients with melanoma. In this study we observed that the baseline AEC values in patients that will develop irAEs are higher than in those without irAEs and, among the former, the values are lower for patients with toxicity G1-G2 vs G3-G4. We also found an increase of the mean AEC from baseline to the onset of the first irAE. Of the patients who experience toxicity, most have an upward trend in AEC at the onset of the first irAE. Compatibly with all the limitations of a retrospective analysis, our is the first experience exploring the role of the eosinophil count in the development of irAEs in mRCC patients treated with ICIs, and a prospective study is ongoing in our Unit to confirm the role of the eosinophil count in patients treated with ICIs.

Abstract PS7-19: Pre/perimenopausal (preMeno) women receiving palbociclib (PAL) for hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (ABC) in a real-world setting: Treatment patterns from POLARIS

Abstract Background: POLARIS is an ongoing, prospective, real world, noninterventional study in patients (pts) with HR+/HER2– ABC receiving PAL. This interim report describes real-world PAL use in preMeno pts. Methods: POLARIS has a targeted enrollment of 1500 pts from ~110 sites in the United States and Canada. Using patient data collected from medical charts and physician surveys, baseline demographics, clinical characteristics, and treatment patterns were analyzed descriptively in self-reported preMeno pts with ABC. Results: At the data cutoff of May 20, 2020, 1208 pts were enrolled; 134 (11.1%) from 61 sites were preMeno, of whom 14.2% completed ≥6 months of PAL treatment. Among 134 preMeno pts (74.6%) who received first-line (1L) therapy, 69.0% received PAL+letrozole (LET) or anastrozole, 28.0% PAL+fulvestrant, and 3.0% PAL+exemestane. Median disease-free interval was 39.3 (range: 0 to 236) months; median treatment-free interval was 14.8 (-3 to 134) months. Of 34 pts (25.4%) who received PAL as second or later line (≥2L), 23.8% previously received hormonal therapy, 28.6% chemotherapy, and 14.3% both. The majority of pts (96.27%) initiated PAL at 125 mg regardless of line of therapy (Table). During the first PAL treatment cycle, 2.9% of all preMeno pts, 1% of 1L pts, and 8.8% of ≥2L pts had a dose reduction; 8.2%, 9%, and 5.9%, respectively, had an interruption. Dose reductions/interruptions peaked in cycle 2 (11.9%/15.7%); 56.67% of these modifications were due to adverse events. Conclusions: PAL is routinely prescribed in clinical practice for preMeno women with HR+/HER2- ABC. The majority of preMeno pts in this real-world dataset received PAL+LET as 1L ABC treatment; PAL was primarily initiated at the recommended dose (125 mg) and was well tolerated with few dose modifications required. Clinical trial identification: Pfizer (NCT03280303) Table.CharacteristicFirst-Line Pre/Perimenopausal Patients (n=100)Second or Later Line Pre/Perimenopausal Patients (n=34)Pre/Perimenopausal Patients (N=134)Age at study enrollment, yMedian (range)44 (22-61)42.5 (27-58)44 (22-61)Distribution, n (%)<4032 (32.0)12 (35.3)44 (32.8)40–5045 (45.0)17 (50.0)62 (46.3)51–6923 (23.0)5 (14.7)28 (20.9)Race, n (%)White73 (73.0)26 (76.5)99 (73.9)Black or African American16 (16.0)4 (11.8)20 (14.9)Asian1 (1.0)1 (2.9)2 (1.5)Native Hawaiian or other Pacific Islander2 (2.0)0 (0.0)2 (1.5)American Indian or Alaska Native1 (1.0)0 (0.0)1 (0.7)Other3 (3.0)2 (5.9)5 (3.7)Not reported because of confidentiality regulations4 (4.0)1 (2.9)5 (3.7)Hispanic/Latino ethnicity, n (%)10 (10.0)3 (8.8)13 (9.7)Disease status, n (%)Visceral35 (35.0)13 (38.2)48 (35.8)Nonvisceral61 (61.0)17 (50.0)78 (58.2)Not reported4 (4.0)4 (11.8)8 (6.0)Bone metastases at mBC diagnosis, among patients with metastatic (stage IV) disease at study enrollment, n (%)Bone only40 (40)8 (23.5)48 (35.8)Bone plus other metastases32 (32)13 (38.2)45 (33.6)Disposition of patient ABC/mBC diagnosis at study at study enrollment, n (%)Recurrent from earlier stage (Stage 0-III)72 (72.0)18 (52.9)90 (67.2)De novo (Newly diagnosed Stage IV at enrollment)26 (26.0)15 (44.1)41 (30.6)Not reported2 (2.0)1 (2.9)3 (2.2)ECOG performance status at study enrollment (N, %)041 (41)15 (44.1)56 (41.8)126 (26)7 (20.6)33 (24.6)28 (8)3 (8.8)11 (8.2)32 (2)0 (0)2 (1.5)Not reported23 (23)9 (26.5)32 (23.9)Starting dose, first cycle of PAL treatment n (%)125 mg96 (96.0)33 (97.1)129 (96.3)100 mg2 (2.0)1 (2.9)3 (2.2)75 mg2 (2.0)0 (0.0)2 (1.5)Reason for first cycle starting dose <125 mg, n (%)Patient preference0 (0.0)1 (100)1 (25.0)Other3 (100)0 (0.0)3 (75.0) Citation Format: Meghan S Karuturi, Adnan Garrett, Joanne L Blum, Jay Anderson, Erin Jepsen, Timothy Pluard, Thomas Stanton, Kenneth Manning, Joseph C Cappelleri, Faith Beery, Yao Wang, Debu Tripathy. Pre/perimenopausal (preMeno) women receiving palbociclib (PAL) for hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (ABC) in a real-world setting: Treatment patterns from POLARIS [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-19.

Abstract PS7-25: Geicam/2014-03 (RegisTEM): A prospective registry of unresectable locally advanced or metastatic breast cancer: Characteristics of a subset of patients with triple negative subtype

Abstract Background: There is limited prospective data for advanced breast cancer (ABC) patients (pts), both unresectable locally (ULABC) or metastatic (MBC) treated as per clinical practice. RegistEM study will provide epidemiological, pathological and clinical data, including treatments for different disease settings. Understanding the real distribution of BC subtypes is the primary objective. This is a non-interventional cohort study that will enroll around 1,867 pts (males or females) with ABC diagnosed from January 2016 to December 2019, either after recurrence or as first diagnosis, in 38 Spanish sites. Triple negative (TN) subtype histologically confirmed in the primary tumor (PT) and/or in a metastatic tumor lesion (M1) and recurrent disease from early stage, has been identified as an interesting group from a clinical perspective for detailed analysis. Methods: In this analysis, we describe the characteristics of 131 pts with TN subtype by local evaluation at any disease stage [in PT only (PT group), in M1 only (M1 group) and in both PT and M1 (group PT/M1)] until progressive disease (PD) at first-line and data of therapeutic options at second-line. Results: Distribution of 131 pts within the groups; PT, M1 and PT/M1, was 45.8%, 27.5% and 26.7%, respectively. To date, 32.1% pts have shown a change of subtype along their BC evolution, >50% of those changes was between TN and Luminal B HER2-. Median time from early BC (EBC) diagnosis until recurrent disease in terms of MBC or ULABC was 33.4 months (mo) (PT and PT/M1-26.0 mo; M1-60.2 mo), with the majority of pts recurring >12 mo (91.6%). Median age at diagnosis of ABC was 58 years (range 31-84), most pts were Caucasian (96.9%), female (99.2%) and postmenopausal (65.6%). Family history of BC and/or ovarian cancer was reported in 41.2% pts, a hereditary-risk genetic test was performed in 21.4% pts (8 pts with BRCA1/2 mutation). Lung (40.5%), lymph nodes (35.9%), bone (35.9%) and liver (20.6%) were the most frequent metastatic locations; central nervous system metastases were developed by 12.2% pts. The rate of visceral involment (60-70% pts) was similar among the 3 subgroups. The most frequent first-line therapies were chemotherapy (CT) (51.1%) and CT/biological therapy (BT) (32.8%). Most pts (68.7%) received CT in monotherapy (capecitabine 50%, taxanes 26.1%). Bevacizumab was the most frequent BT within the CT/BT combination (76.7%). Median duration of first line therapy was 4 mo (range 0.2-20.0). Progression to the first-line CT +/- bevacizumab was reported in 51.1% pts with a median time to progression (TTP) of 4.7 mo (range 0.8-19.0) in the whole group, being similar in pts with TN in and PT and PT/M1 (4.4 mo), and higher in pts with TN in M1 (7.1 mo), no statistically significant difference (p=0.38). A second-line therapy was reported in 57.3% pts and the most frequent therapies were CT (78.7%) (eribulin 33.9%, capecitabine 22.0%, platinum-based 22.0%) and CT/BT (12.0%) (CT-containing bevacizumab 77.8%). Median duration of second-line therapy was 3 mo (range 0.03-15.8) and PD has been reported in 80.0% pts. Third-line therapy was reported in 35.9% pts of this subset. Conclusion: In this subset of pts with TN ABC due to recurrent disease, lung, lymph nodes and bone are the most frequent metastatic locations. The main first- and second-line therapies were CT in monotherapy. Progression to the first-line conventional therapy (CT +/- bevacizumab) was reported in 51.1% pts with a median TTP of 4.7 mo (range 0.8-19.0) in the whole group, being similar in pts with TN in PT and PT/M1 (4.4 mo), and higher in pts with TN in M1 (7.1 mo), no statistically significant difference. 36% of the initial subset of pts reported to be treated in the third-line setting. Pts with TN only in M1 seem to have a longer time to progression from EBC. Citation Format: Carlos Jara, César A. Rodríguez, Isabel Alvarez, Catalina Falo, Purificación Martínez, Raquel Andrés, Josefina Cruz, Marta Mori, Encarna Adrover, Ariadna Tibau, Silvia Antolin, Mireia Margeli, Jose L. Alonso, Bella I. Pajares, M. Carmen Camara, J. Jose Miralles, Susana Bezares, Federico Rojo, Sara López-Tarruella, Angel Guerrero- Zotano. Geicam/2014-03 (RegisTEM): A prospective registry of unresectable locally advanced or metastatic breast cancer: Characteristics of a subset of patients with triple negative subtype [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-25.

Abstract PD13-06: Incidence and management of central nervous system metastases in patients with inflammatory breast cancer

Abstract Background: Patients (pts) with inflammatory breast cancer (IBC) have a high risk of central nervous system (CNS) metastasis (mets) with their associated impact on longevity and quality of life. Given evolving CNS-directed treatments, including focal radiation (RT), we compared the proportion of pts diagnosed with asymptomatic CNS mets before and after 2012 as data from Phase III trials in the preceding years (yr) increasingly supported the use of stereotactic radiosurgery (SRS). Specific attention was paid to pts treated with tri-modality therapy (TMT), defined as preoperative systemic therapy, surgery, and RT to determine whether screening for asymptomatic CNS mets would be beneficial. Methods: We retrospectively reviewed the records of pts diagnosed with IBC 1997-2019 and enrolled in an IRB-approved registry at a dedicated IBC center. CNS met-free survival time was defined as the time from IBC diagnosis to date of CNS mets. Alive CNS met-free pts were censored at their latest survival date and death was treated as a competing risk. Cumulative CNS mets incidence was computed. Analyses were stratified based on stage at diagnosis (III vs. de novo IV) and receipt of TMT. For pts completing TMT, the completion date was the starting point for cumulative incidence calculations. Overall survival (OS) was estimated as the time from CNS mets diagnosis to death, with censoring for pts who were still alive. Results: A total of 531 pts were identified; 372 (70%) with stage III; 159 (30%) with de novo Stage IV disease. The median follow-up for pts presenting with stage III and stage IV disease at diagnosis was 5.6 yr and 1.8 yr, respectively. 124 pts had CNS mets; 5 of them at diagnosis. CNS was the first site of mets or progression in 50 pts (9.4%). The cumulative incidence of CNS mets stratified by stage at diagnosis and receipt of TMT is seen in Table 1. Among the 50 de novo Stage IV pts who completed TMT, 4 developed CNS mets prior to surgery. The median overall survival (mOS) after CNS mets was 0.6 yr (IQR: 0.2 - 1.4). Results stratified by tumor subtype were: HER2+ disease (n=51) 1.4 yr (IQR: 0.6 - 3.7); hormone receptor+/HER2- (n=27) 0.6 yr (IQR: 0.2 - 1.2); triple negative (n=40) 0.2 yr (IQR: 0.1 - 0.5). Most pts with CNS mets (87/124, 70%) had neurologic symptoms prompting imaging. There was no difference in the proportion of asymptomatic pts diagnosed with CNS mets prior to or after 2012. Management of CNS mets was as follows: 47 pts (38%) received whole brain RT (WBRT) alone, 22 (18%) SRS alone, 15 WBRT + SRS (12%), 6 resection + WBRT (5%), and 5 resection + SRS (4%). The remaining pts received several of these modalities with or without intrathecal chemotherapy (13, 11%) or CNS treatment was not documented (16, 13%). A total of 258/531 pts have died (49%). Of these pts, 103 (40%) had CNS mets. 67/103 (65%) died due to CNS mets. Conclusions: Among pts with IBC completing TMT, the incidence of CNS mets is as high as 20% both in de novo Stage IV pts at 1 yr and in Stage III pts within 5 yrs, supporting routine surveillance brain MRI among pt with Stage IV disease. The majority of pts continue to receive WBRT with its resultant toxicities. Efforts should be made to identify CNS mets early to facilitate more focal therapy. Future research on systemic therapy with CNS penetrance for IBC patients should be pursued. These data support an ongoing prospective study of screening brain MRI in pts with Stage III IBC to quantify the incidence of CNS mets, utilization of WBRT and impact on neurologic quality of life (NCT04030507). Cumulative Incidence of CNS MetsNo.1 year (95% CI)2 year (95% CI)3 year (95% CI)Stage III (All)3725% (3-7)9% (6-12)18% (14-23)Stage IV (All)15417% (12-24)30% (22-37)42% (32-51)Stage III (TMT)3045% (3-8)11% (8-16)19% (14-24)Stage IV (TMT)4621% (10-34)28% (16-43)35% (20-50) Citation Format: Laura Warren, Samuel M Niman, Marie Claire Remolano, Jean Landry, Faina Nakhlis, Jennifer R Bellon, Meredith M Regan, Beth A Overmoyer. Incidence and management of central nervous system metastases in patients with inflammatory breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD13-06.

Abstract PS10-15: Analysis of systemic therapies following progression on frontline CDK4/6-inhibitor therapy

Abstract Background: Hormone receptor positive (HR+)/human epidermal growth factor receptor 2 negative (Her2-) breast cancers represent the majority of metastatic breast cancers (mBC) among women and are often treated with sequential courses of endocrine therapy (ET) prior to the eventual need for chemotherapy (CT). Inhibitors of cyclin-dependent kinases 4 and 6 (CDK4/6i) block cell cycle progression and decrease proliferation of breast cancer cells. Currently, there are three available CDK4/6i: palbociclib, ribociclib and abemaciclib. Each has been shown to improve progression-free survival (PFS) when given with ET in the frontline setting, compared to ET alone. After progression on CDK4/6i, no standard of care exists for the next line of systemic therapy, and there are no prospective data to help guide clinical practice. Analysis of real-world data may provide insight into optimal second-line treatment for women who have progressed on CDK4/6i therapy. Methods: The nationwide Flatiron Health electronic health record-derived de-identified database was utilized for this analysis. We evaluated patient data collected from 2015-2020 for women with HR+/Her2- mBC who received CDK4/6i as frontline therapy and received a documented second-line systemic therapy. The objectives of this study were to describe what therapies were given as second-line treatment and estimate the real-world PFS (rwPFS) of those therapies. rwPFS was defined as time between initiation of second-line therapy until clinician-recorded progression (or death). Patients (pts) who did not progress or die were considered censored at the end of follow-up or end of second-line therapy. Results: A total of 1,210 pts with HR+/Her2- mBC received CDK4/6i with ET in the frontline setting, including 29.1% with de novo metastatic disease. Average age at diagnosis of metastatic disease was 64.4 years (range 28-84). A majority of pts received palbociclib in the frontline setting (88.2%), and 68.8% received an aromatase inhibitor (AI) as the frontline ET partner. 839 pts subsequently received second-line therapy (Table 1). CDK4/6i was continued as part of second-line treatment in 308 (36.7%) pts. 249 (29.7%) pts received CT as second-line treatment. The proportion of pts who continued CDK4/6i increased from years 2015-2020 (p=0.035), and the proportion who received CT decreased over time (p<0.001). Of the 308 pts who received a CKD4/6i in the second-line setting, most received the same CDK4/6i in both lines; however, pts treated with abemaciclib or ribociclib in the first-line setting were more likely to receive a different CDK4/6i than those who started with palbociclib (54.2% and 39.1%, respectively, vs. 22.3%). Among 160 pts who received CDK4/6i with fulvestrant in the second-line setting, 81.2% had previously received an AI in the frontline setting. Unadjusted rwPFS appears to favor those pts who continued the CDK4/6i (rwPFS 11.27 months, 95% CI [8.87, 13.31]), compared to CT (rwPFS 4.73 months, 95% CI [3.88, 5.59]), fulvestrant (rwPFS 3.68 months, 95% CI [2.99, 5.22]), or mammalian target of rapamycin (mTOR) inhibitor-based therapy (rwPFS 4.27 months, 95% CI [3.23, 6.14]) (p<0.001). Conclusion: The use of CDK4/6i continuation after frontline progression has increased over time, while the use of CT has decreased. Continuation of CDK4/6i in the second-line setting appears to be the strategy with the greatest rwPFS benefit on unadjusted analysis. Adjusted rwPFS and overall survival will be reported in the future. TABLE 1. Second-Line Therapy Used. F, fulvestrant; T, tamoxifenSECOND-LINE THERAPYOverall (N=839)AI23 (2.7%)CDK4/6i4 (0.5%)CDK4/6i + AI97 (11.6%)CDK4/6i + F160 (19.1%)CDK4/6i + F + AI35 (4.2%)CDK4/6i + F + T3 (0.4%)CDK4/6i + T3 (0.4%)CT249 (29.7%)F70 (8.3%)F + AI14 (1.7%)mTOR99 (11.7%)PARP4 (0.5%)PI3K16 (1.9%)T11 (1.3%)Clinical Trial51 (6.1%) Citation Format: James M Martin, Elizabeth A Handorf, Alberto J Montero, Lori J Goldstein. Analysis of systemic therapies following progression on frontline CDK4/6-inhibitor therapy [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS10-15.

Abstract PS7-35: Geicam/2014-03 (registem): A prospective registry of advanced breast cancer: A subset of triple negative breast cancer patients with her2 low expression

Abstract Background: The RegistEM study will provide prospective data from advanced breast cancer (ABC) patients (pts). Understanding the real distribution of BC subtypes is its primary objective. A new nomenclature has been proposed for those cases with HER2 1+ or 2+ by immunohistochemistry and negative in situ hybridization, HER2-low BC. In clinical practice, these tumors are reported as HER2 negative. Methods: This is a non-interventional study that will enroll approximately 1,867 pts with ABC diagnosed from January 2016 to December 2019, either after recurrence or as 1st diagnosis, in 38 Spanish sites. Biological samples (primary and/or metastatic tumor lesions, and blood) collection is part of its procedures. In this analysis (cut-off date 01/April/2020, database ongoing), we describe the characteristics of pts with Triple Negative (TN) subtype and HER2-low expression (as mentioned above). Biomarkers, including HER2, were determined in either primary tumor (PT), M1 or in both, PT and M1. Results: This subset of pts make up 37.4% (n=49) of TN pts considered for this analysis (n=131). Their distribution within the three groups (PT, M1 and PT/M1), was 46.9% (n=23), 42.9% (n=21) and 10.2% (n=5), respectively. These pts were diagnosed with early BC (EBC) and at recurrence, 91.7% presented distant metastases. Median time from EBC diagnosis until recurrent disease in terms of ABC was 29.8 months (mo), with the majority of pts recurring at >12 mo (95.9%), similar to the whole TN subset. Most pts were Caucasian (98%), and at diagnosis of ABC, the median age was 60 years (range 31-84) and 65.3% were postmenopausal. A change of BC subtype was documented in 15/49 (30.6%) pts, with the higher rate in M1 group (52.4%); as opposed to the TN subset, a change to HER2+ disease was reported in 6/15 (40.0%) pts and just after the TN subtype in all cases. Family history of BC and/or ovarian cancer was reported in 42.9% pts and any genetic test to assess the hereditary risk was performed in 30.6% pts. Similarly to TN subset, lung (36.7%), lymph nodes and bone (34.7% each) and liver (24.5%) were the most frequent metastatic locations; central nervous system metastases were developed by 14.3% pts. Visceral involvement was present in 66.7% pts, being this rate lower in M1 compared to PT and PT/M1 groups. The most frequent 1st-line therapies were chemotherapy (CT) (44.9%) and CT/biological therapy (BT) (36.7%). Type of CT mainly included capecitabine (36.4%), taxanes (27.3%), eribulin (13.6%) and platinum-based combinations (13.6%). Most pts received CT as monotherapy (86.4%). Bevacizumab (BVZ) was the most frequent BT associated to CT (77.8%), mainly with capecitabine and/or paclitaxel (72.2%). Progressive disease to 1st-line therapy in the whole group was reported in 73.5% pts (higher than in TN subset), with a median time to progression (TTP) of 5.7 mo (range 1.7-15.0); PT was the group with a higher PD rate. A 2nd-line therapy was reported in 63.3% pts. Similarly to 1st-line setting, the most frequent 2nd-line therapies were CT (74.2%) and CT/BT (12.9%) (with BVZ in 75.0% pts). CT in monotherapy was reported in 69.6% pts (capecitabine 31.3%, eribulin 25.0%). Median duration of this line therapy was 3.0 mo (range 0.6-15.8), PD has been reported in 96.8% pts (similar between groups), and 3rd-line therapy in 25/49 (51.0%) pts. Conclusions: In TN/HER2-low ABC pts, lung, lymph nodes and bone were the most frequent metastatic locations. As opposed to TN subset, HER2+ disease is part of the subtype changes reported. Although the main 1st- and 2nd-line therapies were CT and CT/BT, similarly to TN subset, the rate of pts with PD to 1st- and 2nd-line therapies is higher, and also those pts treated in the 3rd-line setting. Citation Format: Carlos Jara, Isabel Álvarez, César A Rodríguez, Purificación Martínez, Raquel Andrés, Álvaro Rodríguez-Lescure, Diego Malón, Jose Luis Alonso, Encarna Adrover, María José Echarri, Mireia Margeli, Ariadna Tibau, Judith Ramírez, Silvia Antolín, Ruth Campo, Juan José Miralles, Susana Bezares, Federico Rojo, Sara López-Tarruella, Angel Guerrero-Zotano. Geicam/2014-03 (registem): A prospective registry of advanced breast cancer: A subset of triple negative breast cancer patients with her2 low expression [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-35.

Abstract PD2-03: Treatment exposure and discontinuation in the PALLAS trial: PALbociclib CoLlaborative Adjuvant Study of palbociclib with adjuvant endocrine therapy for HR+/HER2- early breast cancer

Abstract Background:Adherence to and tolerability of oral agents for the treatment of hormone receptor positive (HR+) breast cancer in the adjuvant setting may be challenging and can limit drug exposure. Palbociclib (P) is an oral CDK4/6 inhibitor; P in combination with endocrine therapy (ET) has demonstrated efficacy in HR+/HER-2 negative (HER2-) metastatic breast cancer (MBC). The global PALLAS study (NCT02513394) was designed to determine if the addition of P to adjuvant ET improves outcomes over ET alone in early breast cancer. The goal of this analysis is to describe P exposure and discontinuation in PALLAS, and explore any impact on study endpoints. Methods:Pts with stage II-III HR+/HER2- disease were randomized to receive 2 years of P (starting dose 125 mg daily, 3 weeks on, 1 week off) in combination with adjuvant ET (Arm A) or ET alone (Arm B). The primary objective was to compare invasive disease-free survival (iDFS) between arms; secondary endpoints included safety, quality of life, adherence, and translational science. Dose adjustments were defined per protocol in the setting of emergent toxicity. Continuous monitoring of toxicity, dose modifications, and early discontinuations was performed throughout the trial. Statistical analysis included tabulation of dose levels/reductions and reasons for treatment discontinuation, as well as landmark analysis comparing iDFS between those receiving > 12 months (mo) vs < 12 mo of P. Ongoing analyses include exploration of relative dose intensity and modeling of P dose intensity/duration and impact on iDFS. Results:A total of 5760 pts were randomized; 83% had received prior chemotherapy; 68% initiated aromatase inhibitor and 33% tamoxifen, with or without ovarian suppression. Grade 3/4 neutropenia was more common in Arm A vs B (62% vs 0.4%); febrile neutropenia was uncommon (1%). Other all-grade adverse events (AEs) more common in Arm A included other hematologic toxicity, fatigue, upper respiratory infection, nausea, diarrhea, and alopecia. A total of 55% of pts required P dose reduction to 100mg, and 34% to 75 mg, at some point during treatment. At a median follow-up of 23.7 mo at the second interim analysis, no significant difference in iDFS was observed between the arms (3-year iDFS of 87.9% vs 88.4%, HR 0.93, 95% CI 0.76, 1.15); consequently, pts in Arm A stopped P, and all pts moved to long-term follow-up. At time of data cut-off, 32% had completed the planned 2 years of P, 26% were still receiving P, and 42% had discontinued P prematurely. P discontinuation was 18% at 6 mo, 30% at 12 mo, 38% at 18 mo, and 45% projected at 24 mo. A total of 27% of Arm A pts (770 of 2840) discontinued therapy due to AEs, primarily neutropenia (460, 16%) and fatigue (71, 3%). Other reasons for P discontinuation included non-compliance (128, 5%), recurrent disease or second malignancy (104, 4%), or withdrawal of consent (100, 3%). Last observed dose level was 125mg, 100mg, and 75mg for 45%, 22%, and 33% pts, respectively. Among those discontinuing due to AEs, dose level at time of discontinuation was 75mg for 62%, suggesting some discontinuations occurred without maximum dose reduction. Pts who received > 12 mo of P had a 2-year iDFS of 96.6%; those receiving <12 mo had 2-year iDFS of 95.7% (HR 0.86, 95% CI 0.55-1.34). Conclusions:An early analysis of PALLAS has demonstrated that 2 years of adjuvant P in combination with adjuvant ET did not improve iDFS when compared with ET alone in pts with HR+/HER2- breast cancer. While 2 years of adjuvant P was feasible for the majority of pts, 42% discontinued P early, primarily for AEs. Further data examining drug discontinuations and relationships between drug exposure and clinical outcomes will be presented, expanding upon initial point estimates suggestive of a possible explanation of trial results. Citation Format: Erica L. Mayer, Christian Fesl, Amylou Dueck, Michael Gnant, Angela DeMichele, on behalf of the PALLAS study team. Treatment exposure and discontinuation in the PALLAS trial: PALbociclib CoLlaborative Adjuvant Study of palbociclib with adjuvant endocrine therapy for HR+/HER2- early breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD2-03.

Real-world genomic and treatment landscape in advanced colorectal cancer identifies treatment differences pre- and post-ctDNA genomic profiling.

39 Background: Clinical insights gained from real-world data have led to numerous advances in oncology including new and expanded drug approvals and an understanding of real-world clinical utilization. In this precision oncology age, integrating real-world clinical data with genomic data can lead to further advancements. We aimed to understand the genomic and treatment landscape in advanced colorectal cancer (aCRC) by leveraging a uniquely large and detailed clinical-genomic database. Methods: The GuardantINFORM (Guardant Health) database comprises aggregated commercial payer health claims and de-identified records from over 100,000 individuals with comprehensive ctDNA results (Guardant360). GuardantINFORM was queried for patients (pts) with a diagnosis of CRC. Pts with fewer than two pharmacy claims prior to or after the first ctDNA test were excluded from the regimen analysis. Latest claims data was truncated as of 8/31/2020. Results: 10,845 pts had a total of 13,510 ctDNA tests (1 – 19 tests/pt). The first ctDNA test date was from 06/2014 - 06/2020. The majority of pts had one ctDNA test (86.7%) while 5% had three or more tests. 87.9% of ctDNA tests had at least one genomic alteration identified, with the distribution of alterations consistent with prior reports (Table). 78% of pts had at least two pharmacy claims before and/or after the first ctDNA test. Of those pts with at least one CRC treatment, the most commonly prescribed CRC regimens up to one year prior to the first ctDNA test were FOLFOX +/- bevacizumab (16%, 18%), FOLFIRI +/- bevacizumab (17%, 11%), capecitabine (15%), 5-FU (12%), and regorafenib (5.2%). Anti-EGFR mono and combination therapy was reported in 6% and 16% of pts pre ctDNA testing. Immune checkpoint inhibitor (ICPi) mono and combination therapy was reported in 2% and 0.5% of pts. The most commonly prescribed CRC regimens post first ctDNA test were capecitabine (16%), FOLIRI +/- bevacizumab (15%, 13%), tipiracil and trifluridine (15%), FOLFOX +/- bevacizumab (12%, 14%), 5-FU (11%), and regorafenib (10%). Anti-EGFR mono and combination therapy was reported in 8% and 18% of pts post ctDNA testing. ICPi mono and combination therapy was reported in 5% and 1% of pts. Conclusions: Using a large and uniquely detailed clinical-genomic dataset, we produced results that replicate the observed distribution of ctDNA identified mutations present in aCRC. This genomic information combined with real-world clinical data provides valuable insights into the variety of longitudinal treatments, including before and after comprehensive ctDNA genomic profiling, allowing for detailed outcomes research, especially focused on precision oncology. [Table: see text]

Vaccination against tick-borne encephalitis (TBE) after autologous and allogeneic stem cell transplantation

IntroductionOur aim was to assess response and side effects of 4 doses of TBE vaccine to patients (pts) after allo- and autologous stem cell transplantation (SCT). PATIENTS: Included were 104 pts with leukaemia, myeloma and lymphoma, median age 61 yrs. METHODS: Vaccine (FSME-Immun®) was given at 9, 10, 12, and 21 months post-transplant. Serum samples were obtained before and after vaccinations. Healthy controls (n = 27) received 3 vaccinations. Assessments of TBE specific IgG antibodies were performed by Enzygnost anti-TBE ELISA test (Siemens, Sweden). ResultsAntibody levels (>12 U/mL; “seropositivity”) were seen in 77% and 80% of pts after allo- and autoSCT; IgG levels; 89 vs 94 U/mL. Ongoing chronic GvHD and immunosuppression (n = 29) was associated with sero-negativity in the last sample (p = 0.007). All controls (n = 27) developed protective antibody levels. ConclusionsTBE vaccination was safe, and 4 doses starting 9 months post-SCT, induced seropositivity in a vast majority of pts.

Adjuvant therapy in patients with resected pancreatic adenocarcinoma: Analysis of treatment allocation patterns in a Canadian provincial institution.

383 Background: In recent years adjuvant therapy (AT) for pancreatic cancer has evolved. Improved overall survival (OS) was demonstrated first in 2017 with gemcitabine and capecitabine (GemCap), and then further improved in 2018 with FOLFIRINOX compared to gemcitabine (gem) alone. Given these options, we retrospectively reviewed the patterns of AT allocation in the province of British Columbia (BC) during these periods of adoption of newer AT regimens. Methods: Patients (pts) treated at BC Cancer centers between January 2017 to June 2018 (the GemCap era), and July 2018 to July 2019 (the FOLFIRINOX era), who had undergone curative intent resection and received at least one cycle of AT were included for chart review. Patient and disease characteristics, treatment details, and stated rationale for choice of AT regimen were collected. Analyses were performed with one-way ANOVA for comparison of means between regimens, and Chi-squared or Fisher Exact tests to determine correlation between clinicopathologic factors and likelihood of undergoing a given AT regimen. Results: 122 pts were identified: 67 treated in the GemCap era (gem: 25, 37%, and GemCap: 42, 63%) and 55 treated in the FOLFIRINOX era (gem: 18, 33%, GemCap: 18, 33%, FOLFIRINOX: 19, 34%). Examined variables included age, gender, ECOG, T and N stage, margins, lymphovascular invasion and post-operative CA19-9. In the GemCap era, use of GemCap vs Gem was associated with younger average age (p = 0.001) and positive lymph node status (91% vs. 60%, p = 0.005). In the FOLFIRINOX era, use of gem AT was associated with a delayed time from surgery to consultation. (p = 0.036) AT assignment was not influenced by high volume vs low volume centre in the GemCap era; however, pts were more likely to receive GemCap in low-volume centres during the mFOLFIRINOX era (p = 0.045). The most common stated reasons for choice of a less intense AT regimen were pt comorbidities or functional status (GemCap era: 24% and FOLFIRINOX era: 31%). Conclusions: Despite improvements in survival with newer AT regimens, the majority of pts in our real-world setting were assigned a less intense AT regimen. Within the limits of a small sample size, significant pt or disease factors predictive of AT assignment were not identified aside from age and lymph node positivity in the GemCap era, and time from surgery to consultation in the FOLFIRINOX era. Efforts to improve adoption of newer AT regimens and optimize pt eligibility for FOLFIRINOX are warranted.

Phase II trial of bintrafusp alfa in patients with metastatic MSI-H cancers following progression on immunotherapy.

79 Background: Microsatellite instability-high (MSI-H) tumors are characterized by deficient mismatch repair, high tumor mutation burden, and exceptional anti-tumor responses to immunotherapy. While durable disease control is often observed for advanced MSI-H cancers treated with immune checkpoint blockade (ICB), some patients (pts) experience treatment resistance. In melanoma and urothelial cancer, acquired resistance to ICB has been associated with increased signaling of the immunosuppressive TGF-β pathway. Bintrafusp alfa (BA) is a first-in-class bifunctional fusion protein composed of the extracellular domain of the TGF-βRII receptor (a TGF-β “trap”) fused to a human IgG1 monoclonal antibody blocking PD-L1. Methods: In this phase II study (NCT03436563), pts with MSI-H metastatic solid tumors who had progressed on prior ICB were eligible. Pts received 1200 mg BA intravenously every 14 days. Paired tumor biopsies were collected for biomarker analysis. The primary objective was to estimate response rate (RR) per iRECIST. Median progression-free survival (PFS) and overall survival (OS) were calculated according to the Kaplan-Meier method. Adverse events (AEs) were assessed according to CTCAE v5.0. Results: 15 pts [arising from the colon/rectum (12), pancreas (1), duodenum (1), appendix (1)] were enrolled. Median duration of prior ICB before progression was 7.2 months (range, 1.8-24). All pts were evaluable for toxicity, and 14 for response. There was 1 grade 3 treatment-related AE (adrenal insufficiency) and 1 grade 5 treatment-related immune AE (hepatic failure). Median number of doses with BA was 4 (interquartile range, 2-4). There were 3 pts with stable disease and 11 with progressive disease as best response. RR was 0% (95% confidence interval (CI), 0-24%), and disease control rate was 21% (95% CI, 5-51%). Median PFS and OS were 1.8 months (95% CI, 1.5-5.7) and 9.1 months (95% CI, 5.3-not estimable), respectively. One pt with colorectal cancer demonstrated sustained stable disease (20.5 months) with BA. Conclusions: Dual inhibition of TGF-β and PD-L1 by BA did not demonstrate significant anti-tumor activity in the majority of pts with MSI-H metastatic cancer who had progressed on prior ICB. One pt did experience prolonged clinical benefit from BA. Ongoing correlative studies may inform on the effect of TGF-β and PD-L1 modulation by BA within the tumor microenvironment. Clinical trial information: NCT03436563.

Socioeconomic status (SES) and survival outcomes in patients with gastrointestinal (GI) cancers: An analysis of 1.4 million patients in the National Cancer Database (NCDB).

458 Background: SES and access to care are factors that may impact patient outcomes. We examined the impact of SES on survival in patients (pts) with GI cancers. Methods: Data obtained from the NCDB were used to examine the association between SES and outcomes of GI cancer pts. Pts were categorized by income and education levels. Logistic regression, Cox proportional hazards models, and chi-square tests were used to examine the differences between the groups. Results: A total of 1,409,177 pts diagnosed with GI cancers between 2004 and 2016 were retrospectively studied (table). The majority of pts were male (54.3%), and 83.7% were white, 11.5% black, and 4.7% of other races. Of the entire cohort, 31% of pts lived in the highest income areas, whereas 18.3% were in the lowest and 50.6% in middle-income areas; 23% lived in the highest high school graduation rate (>93%) areas, whereas 17.4% lived in the lowest graduation rate (< 79%) areas; and 82.4% resided in metropolitan areas. Pts in the lowest compared to highest income areas were more likely to be black (OR: 6.5, 6.4-6.6), uninsured (2.9, 2.8-3.0), or have Medicaid (4.13, 4.04-4.22), and have a Charlson-Deyo score ≥ 1 (1.35, 1.33-1.36). In the multivariate analysis, cancer type, stage, tumor differentiation, income, education, insurance status, gender, race, Charlson-Deyo score, and type of treatment center were independent predictors for survival. After controlling for other factors, black pts had a 3% increased risk of death (HRadj = 1.03; 1.02-1.03; p < 0.001). Pts from lowest vs highest education areas had a 2% increased risk of death (HRadj = 1.02; 1.01-1.03; p < 0.001). Pts from the lowest income vs highest income areas had a 13% increased risk of death (HRadj = 1.13; 1.12-1.14; p < 0.001). Pts with Medicaid insurance had a 33% (HRadj: 1.33, CI 1.32-1.34, p < 0.001) and uninsured pts had 22% (HRadj: 1.22 (1.20-1.23, p < 0.001) increased risk of death compared to pts with private insurance. Pts from urban or rural areas vs metropolitan areas had a 1% increased risk of death (HRadj = 1.01; 1.00-1.02; p < 0.001). Conclusions: Low SES is associated with worse survival in pts with any GI cancer. Pts with low-income status and Medicaid or no health insurance had the highest risk of mortality. These stark inequities must be addressed with renewed efforts to identify, treat, and better support pts at highest risk for poor outcomes. [Table: see text]

Prognostic impact of rapid reduction of involved free light chains in multiple myeloma patients under first-line treatment with Bendamustine, Prednisone, and Bortezomib (BPV)

IntroductionLight chain involvement is observed in almost every patient (pt) with newly diagnosed multiple myeloma (MM). Owing to a relatively short half-life, rapid reduction in the involved free light chain (iFLC) is of potential prognostic value.MethodsThis retrospective analysis included 92 pts with newly diagnosed MM treated with bendamustine, prednisone, and bortezomib (BPV).ResultsAfter a median number of two (range 1–5) BPV cycles, the majority of pts (n = 86; 93%) responded with either sCR (n = 21), CR (n = 1), nCR (n = 25), VGPR (n = 20), or PR (n = 19). PFS and OS at 48 months were 39% and 67%, respectively. At baseline, 79 out of 92 pts (86%) had iFLC levels above the upper standard level and an abnormal ratio of involved to uninvolved free light chain ≥ 8. In a subgroup analysis of these pts, we evaluated the prognostic importance of an early reduction of the iFLC during the first two BPV cycles. A reduction ≥ 50% of the iFLC on day 8 of the first cycle was observed in 31 of 69 pts. These pts had a significantly better median PFS of 49 months as compared to 20 months in 38 pts with a lower iFLC reduction (p = 0.002). In contrast, OS did not differ significantly with a 48 months survival of 77% vs 69% (p > 0.05).ConclusionThese results indicate that a rapid decrease in the iFLC on day 8 is an early prognostic marker for newly diagnosed MM pts undergoing BPV treatment.

Analysis of Quality-of-Life (QoL) in Patients Receiving NEPA for Prevention of Chemotherapy-Induced Nausea (CINV) and Vomiting

Introduction: Chemotherapy-induced nausea and vomiting (CINV) is a common and distressing side effect that has a detrimental impact on QoL. For pts receiving highly emetogenic chemotherapy (HEC), which includes those on anthracycline-cyclophosphamide (AC)-based regimens, a triple combination of a neurokinin-1 receptor antagonist (NK1 RA), a 5-hydroxytryptamine-3 (5-HT3) RA and dexamethasone is recommended by the NCCN and MASCC/ESMO. The complexity of the NK1 RA-based schedules may be a reason for the low adherence to antiemetic guidelines and a not sufficient control of CINV in pts receiving HEC and MEC. NEPA is the only available fixed-combination antiemetic. It is composed of an NK1 RA, netupitant (300 mg) and a 5-HT3 RA, palonosetron (0.50 mg); thus, it acts by blocking two main emetic pathways in a single dose and eases compliance to guidelines. Methods: Prospective, non-interventional study at 162 sites in Germany from 09/2015 to 03/2018. The aim was to determine QoL of adult cancer pts receiving NEPA for the prevention of nausea and vomiting associated with 1 or 2 day HEC or MEC in daily clinical practice. The primary outcome was measured via the Functional Living Index-Emesis (FLIE) questionnaire. FLIE questionnaires were analyzed according to the FLIE scoring and administration manual v12; higher scores correlated to better performance on daily life activities due to the lower occurrence of nausea and vomiting. 'No impact on daily life (NIDL) activities' for individual nausea and vomiting domains was defined as a FLIE score higher than 53.8; NIDL for the combined domains of nausea and vomiting was defined as a FLIE score higher than 108. Secondary objectives included evaluating effectiveness, as determined by measuring the rate of complete response (CR) and rescue medication, as well as safety outcomes. Efficacy was documented by the treating physicians and via patient diaries for 3 Ctx cycles within 24 hrs and on 4 additional d after Ctx. Safety, additional medication and physicians' overall satisfaction was reported via eCRF. Results: A total of 2429 pts were enrolled, 2405 of whom were assessed for eligibility; of these, 2173 were included in the final analysis and constitute the full analysis set population (FAS). Evaluable FLIE questionnaires were collected from 1886 (88%) pts in cycle 1, 1795 (88%) pts in cycle 2 and 1698 (86%) pts in cycle 3. A total of 1389 pts received HEC and 764 MEC in cycle 1. The majority of pts (91%) were scheduled to receive 1-day ctx at study entry. More than half of the pts (1230, 56%) received anthracycline/cyclophosphamide-(AC), 19% carboplatin-, 8% cisplatin-, 7% oxaliplatin- and 9% other CTs. NIDL due to vomiting during cycle 1 was reported by 84% of pts in the HEC group and 82% in the MEC group. These frequencies were maintained in cycles 2 and 3. NIDL due to nausea increased from 54% in cycle 1 to 58% in cycle 3 for pts receiving HEC, and from 59% in cycle 1 to 66% in cycle 3 for pts in the MEC group. The rates for the combined domain of NIDL due to nausea and vomiting were consistent across cycle 1 (64%) and in cycles 2 and 3 (66% in each cycle) for pts in the HEC group, while the rates increased from 67% in cycle 1 to 73 and 74% in cycles 2 and 3, respectively, for pts receiving MEC. The CR rate (no emesis and no use of rescue medication) was 89% in the acute phase (0-24 h), 87% in the delayed phase (25-120 h) and 83% in the overall period (0-120 h) in cycle 1. The no significant nausea (NSN) rate was 79 % in the acute, 75 % in the delayed and 67 % in the overall phase in cycle. The majority of physicians (≥89%) and pts (≥86%) rated the effectiveness of NEPA prophylaxis as 'very good' or 'good' during all three ctx cycles. The most common NEPA-related AEs, which occurred in >1% of pts in the overall study period, were fatigue (3%), constipation (3%), nausea (2%) and insomnia (2%). There were no reports of NEPA-related deaths. Conclusions: Real-life data show that NEPA was effective in the prevention of chemotherapy-induced nausea and vomiting in cancer patients. NEPA had beneficial effects on the quality of life and was highly effective in the acute and delayed phase of HEC and MEC. NEPA antiemetic effectiveness was rated highly both by patients and physicians. Disclosures Karthaus: RIEMSER: Consultancy, Honoraria. Schilling:Riemser: Honoraria.

Hematopoietic Progenitor Cell Mobilization and Collection for Autologous Hematopoietic Cell Transplantation in AL Amyloidosis: A Single Center Experience

Hematopoietic Progenitor Cell Mobilization and Collection for Autologous Hematopoietic Cell Transplantation in AL Amyloidosis: A Single Center Experience