Negative Patients Research Articles

Association between Group B Streptococcus and Clinical Chorioamnionitis by Gestational Week at Delivery-A Multicenter Cohort Study.

In the era of group B Streptococcus (GBS) screening and intrapartum antibiotic prophylaxis (IAP), GBS colonization has been associated with a lower risk of chorioamnionitis, possibly due to a protective effect of IAP. We sought to confirm this finding and assess whether this association varies by gestational week at delivery. We performed a retrospective cohort study of term (37.0-42.6 weeks), singleton parturients with known GBS status who delivered from 2005 to 2021 at two academic medical centers in Israel. We excluded patients who underwent planned cesarean, out of hospital birth, or had a fetal demise. Patients received GBS screening and IAP for GBS positivity as routine clinical care. The primary outcome was a diagnosis of clinical chorioamnionitis as determined by the International Classification of Diseases 10th Revision code, compared between GBS-positive and -negative groups, and assessed by gestational week at delivery. Of 292,126 deliveries, 155,255 met inclusion criteria. In total, 30.1% were GBS positive and 69.9% were negative. GBS-positive patients were 21% less likely to be diagnosed with clinical chorioamnionitis than GBS-negative patients, even after controlling for confounders (1.5 vs. 2.2%, adjusted odds ratio: 0.79, 95% confidence interval: 0.68-0.92). When assessed by gestational week at delivery, there was a significantly greater difference in rates of clinical chorioamnionitis between GBS-positive versus GBS-negative groups with advancing gestational age: 1.5-fold difference at 38 to 40 weeks, but a twofold difference at 42 weeks. The risk of clinical chorioamnionitis remained stable in the GBS-positive group, but increased significantly in the GBS-negative group at 41- and 42-week gestation (2.0 vs. 2.9%, p < 0.01 at 41 weeks; up to 3.9% at 42 weeks, p < 0.01). In a large multicenter cohort with universal GBS screening and IAP, GBS positivity was associated with a lower risk of chorioamnionitis, driven by an increasing rate of chorioamnionitis among GBS-negative patients after 40 weeks. · GBS positivity and IAP may be associated with lower risk of chorioamnionitis.. · GBS-positive patients were less likely to be diagnosed with chorioamnionitis.. · This difference increased with advancing gestational age after 40 weeks..

Clinicopathologic Characteristics of MYC Copy Number Amplification in Breast Cancer.

Introduction. MYC overexpression is a known phenomenon in breast cancer. This study investigates the correlation of MYC gene copy number amplification and MYC protein overexpression with coexisting genetic abnormalities and associated clinicopathologic features in breast cancer patients. Methods. The study analyzed data from 81 patients with localized or metastatic breast cancers using targeted next-generation sequencing and MYC immunohistochemical studies, along with pathological and clinical data. Results. Applying the criteria of MYC/chromosome 8 ratio ≥5, MYC copy number amplified tumors (n = 11, 14%) were associated with invasive ductal carcinoma (91% vs 68%, P = .048), poorly differentiated (grade 3, 64% vs 30%, P = .032), mitotically active (Nottingham mitotic score 3, 71% vs 20%, P = .004), estrogen receptor (ER)-negative (45% vs 12%, P = .008), and triple-negative (56% vs 12%, P = .013) compared to MYC non-amplified tumors. Among MYC-amplified breast cancer patients, those with triple-negative status showed significantly shorter disease-free survival time than non-triple negative MYC-amplified patients (median survival month: 25.5 vs 127.6, P = .049). MYC amplification is significantly associated with TP53 mutation (P = .007). The majority (10 of 11; 91%) of MYC-amplified tumors showed positive c-MYC immunostaining. Conclusion. Breast cancers with MYC copy number amplication display distinct clinicopathologic characteristics indicative of more aggressive behavior.

Evolution and prognostic significance of HER-2 changes from primary to residual disease in patients with HER-2–negative breast cancer receiving neoadjuvant chemotherapy.

583 Background: HER-2 changes during the neoadjuvant chemotherapy has not been thoroughly evaluated. The current study aimed to analyze the HER-2 status changes from primary to residual disease in HER-2 negative patients after neoadjuvant chemotherapy and evaluate its impact in survival outcomes. Methods: HER-2 negative breast cancer patients with residual disease after NACT who had paired pre- and post-therapeutic HER2 testing results were retrospectively analyzed. Data on clinical and pathological characteristics, treatment information, and survival outcomes were collected for all eligible patients. HER2 changes from the primary to residual disease were described and logistic regression were performed to identify factors associated with HER2 changes. The Kaplan–Meier method and multivariate Cox regression were used for survival analysis. Results: 571 HER-2 negative breast cancer patients with residual disease after NACT were enrolled, including HER2-zero (35.2%, n=201) and HER2-low (64.8%, n=370) patients before NAC. The overall rate of HER-2 changes rate was 32.4% (negative to positive 1.1%, low to zero 15.4%, zero to low 15.9%). Among the patients with HER-2-zero before NAC, patients with HER-2 changes (zero to low) were likely to be hormone receptor positive (68.1% vs 36.7%, P&lt;0.0001) and had a higher proportion of patients with Ki-67≤20 (Ki-67≤20 27.5% vs 15.6%, P=0.035). Among the patients with HER2-low before NAC, a higher proportion of hormone receptor negative were observed in HER2 changes patients (low to zero) (31.8% vs 18.4%, P=0.008) and the Ki-67 is relatively high in HER-2 changes patients (Ki-76 &gt; 20 73.9% vs 65.0% P=0.030). Multivariable logistic regression analyses showed patients with hormone receptor positive before NAC were related to underwent HER2-zero transferring to HER2-low (OR, 3.436, P&lt;0.0001). The median follow-up time was 50.0 months. In the HER-2 zero group, HER2 changes (zero to low) was significantly associated with better DFS comparing with constant HER2-zero (HR0.49, P=0.01) after adjustment, with 4-year DFS rate was 80.1%,55.7% (Log-rank P =0.033). Subgroup analysis showed that in the hormone receptor positive subgroup, patients with HER2 zero to low has a significant better DFS than patients with constant HER2-zero (Log-rank P=0.037). In the HER2-low group, no significant differences in survival outcomes between constant HER2-low and HER2 low to zero (HR1.07, P=0.778). Conclusions: HER2 status showed instability from primary tumor to residual disease after neoadjuvant treatment. HER2 changes (zero to low) was associated with better DFS in HER-2 zero patients.

A method to comprehensively identify germline SNVs, INDELs and CNVs from whole exome sequencing data of BRCA1/2 negative breast cancer patients.

In the rapidly evolving field of genomics, understanding the genetic basis of complex diseases like breast cancer, particularly its familial/hereditary forms, is crucial. Current methods often examine genomic variants-such as Single Nucleotide Variants (SNVs), insertions/deletions (Indels), and Copy Number Variations (CNVs)-separately, lacking an integrated approach. Here, we introduced a robust, flexible methodology for a comprehensive variants' analysis using Whole Exome Sequencing (WES) data. Our approach uniquely combines meticulous validation with an effective variant filtering strategy. By reanalyzing two germline WES datasets from BRCA1/2 negative breast cancer patients, we demonstrated our tool's efficiency and adaptability, uncovering both known and novel variants. This contributed new insights for potential diagnostic, preventive, and therapeutic strategies. Our method stands out for its comprehensive inclusion of key genomic variants in a unified analysis, and its practical resolution of technical challenges, offering a pioneering solution in genomic research. This tool presents a breakthrough in providing detailed insights into the genetic alterations in genomes, with significant implications for understanding and managing hereditary breast cancer.

Results from METIS (EF-25), an international, multicenter phase III randomized study evaluating the efficacy and safety of tumor treating fields (TTFields) therapy in NSCLC patients with brain metastases.

2008 Background: For non-small cell lung cancer (NSCLC) with brain metastases (BM) stereotactic radiosurgery (SRS) is the current preferred therapy. Due to frequent intracranial failures, there is a high unmet need for salvage therapies. Whole brain radiotherapy (WBRT) reduces intracranial failure but used less frequently due to cognitive consequences. Tumor Treating Fields (TTFields) are electric fields that disrupt cancer cell division and have shown improved survival and safety in patients with glioblastoma and metastatic NSCLC. Phase 3 METIS trial [NCT02831959] aimed to evaluate the efficacy and safety of TTFields therapy in NSCLC patients with BM treated with SRS, specifically in terms of lengthening time to intracranial progression without cognitive decline. Methods: Mutation negative (M-) NSCLC patients with 1–10 BM were randomized 1:1 to receive stereotactic radiosurgery (SRS) followed by Tumor Treating Fields (TTFields; 150 kHz) therapy with best supportive care (BSC) or SRS followed by BSC. Patients with Karnofsky Performance Status (KPS) ≥70, newly diagnosed with one inoperable or 2–10 supra-/infratentorial brain metastases suitable for SRS and receiving optimal extracranial disease therapy were included. Exclusions were prior WBRT and single operable or recurrent brain metastases. Primary endpoint was time to first intracranial progression (RANO-BM) based on cumulative risk. Patients were followed every two months until second intracranial progression. Cognition and patient quality of life (QoL) were evaluated. Results: Between July 2016 and September 2022, 298 patients were randomized. Baseline characteristics were balanced: median age was 63.5 (range 37-84) years, 37.6% females, majority of patients had a KPS ≥ 80, median time from initial NSCLC diagnosis was 1.8 months (range: 0.2-55.7), 77% had adenocarcinoma. Median treatment duration of TTFields was 16 weeks, with a median usage time of 67%. Primary endpoint, time to intracranial progression from SRS, was significantly prolonged with SRS followed by TTFields therapy with BSC vs. TTFields plus BSC arm (median of 21.9 vs. 11.3 months); HR=0.67 [0.48-0.93], p=0.02. TTFields-related AEs were mainly dermatological, and Grade ≤2. TTFields therapy also improved deterioration-free survival of global health status, physical functioning, and fatigue according to QoL, and did not negatively impact cognition. Conclusions: METIS study met its primary endpoint, demonstrating that TTFields therapy following SRS in mutation negative NSCLC patients with BM, significantly prolongs time to intracranial progression and could postpone WBRT, without QoL and cognition decline. Clinical trial information: NCT02831959 .

Evaluation of candidemia risk factors and Candida species distribution in intensive care units among patients with and without COVID-19.

To assess the risk variables related to the types of candidemia for each patient, who was admitted into the intensive care unit regardless of the patient with or without complete diagnosis of COVID-19, during the period of March 2019 to December 2022. The evaluation comparison of demographic and clinical data of COVID-19 positive and negative patients with candidemia confirmed in blood, 113 cases were assessed. Variables such as gender, age, age of hospitalization, history of hospitalization, concurrently infection, The acute physiology and chronic health evaluation-II scores, comorbidity checking, intubation, central venous catheter use, parenteral nutrition use, steroid use, antibiotic use, lymphopenia, and laboratory variables were evaluated. Candida species distribution, antifungal susceptibility in blood culture were determined. Coronavirus disease-19 was present in 62.8% of cases confirmed candidemia, and these cases were significantly different from COVID-19 negative cases. Significance was found in more intubation, central venous catheter use, parenteral nutrition, and steroid therapy in Group 2. There was no significance with species distribution and associated infection. In total, COVID-19 positive had higher hemoglobin, aspartate aminotransferase, alanine transaminase, and white blood cell levels, which may be associated with the possibility of revealing and controlling candidemia. Candida albicans and Candida Parapsilosis (C. parapsilosis) are the species seen in infected COVID-19 patients, while C. parapsilosis and Candida tropicalis are found in non-COVID-19 ones. Risk factors were intubation, parenteral nutrition, central venous catheter, and steroid in the COVID-19 group.

Cisplatin monotherapy as a treatment option for patients with HER-2–negative breast cancer facing hepatic visceral crisis or impending visceral crisis: A single-center cohort study.

e13057 Background: The international consensus guidelines, ESO-ESMO's fifth edition, characterize visceral crisis (VC) in advanced breast cancer (ABC) as a swift rise in bilirubin during disease progression. The guidelines also briefly address the impending VC (IVC) definition. Systemic treatment data for hepatic VC/IVC are scarce and lacking in international guidelines regarding BC treatment. This study explores cisplatin monotherapy's safety and efficacy in HER2-negative BC patients with hepatic IVC/VC. Methods: In this retrospective cohort study conducted at a Reference Cancer Center in Southern Poland, data from HER2 negative ABC patients who underwent cisplatin monotherapy (60-80mg/m2, every 3-4 weeks) between 2016 and 2023 were examined. Hepatic VC followed ABC5 definition of rapid bilirubin elevation &gt;1.5 times the upper limit of normal (ULN) due to diffuse liver metastases, in the absence of biliary tract obstruction or Gilbert's syndrome; IVC was characterized by rapid, symptomatic liver progression, a majority of liver involvement, with ALT or AST &gt;2 x ULN, and significant increases in LDH, alkaline phosphatase, or GGTP. Results: The study included 33 female participants (24 hormonal positive) with a mean age of 53.8 years (range 34-77). Among them, 10 were identified with hepatic VC, and 23 with IVC. Median number of previous palliative systemic treatment lines was 2 (range: 0-5). The median progression-free survival was 1.87 months and the median overall survival was 2.67 months. Patients received median 1 cycle of cisplatin (1-6): 17 patients received only one cycle, 6 patients two cycles and 10 patients ≥three cycles. Using the Conditional Inference Trees algorithm allowed to assess that patients with performance status (PS) 0 or 1 (15 patients) had a 66.67% chance of achieving stable disease (SD) or partial regression (PR) as the best response, while patients with PS ≥2 (18 patients) had a 5.6% chance of achieving SD or PR as per Response Evaluation in Solid Tumors 1.1 Criteria (median time from cisplatin initiation to imaging studies 2.23 months). Eight patients experienced adverse events of grade ≥3, such as fatigue or nephrotoxicity leading to dose reduction in 5 cases and treatment discontinuation in 2. Conclusions: The differentiation between IVC and VC lacks precision. Due to the hepatotoxicity of BC-active drugs, specific recommendations for systemic treatment are lacking. Our study explored cisplatin's potential use, finding it to be a feasible choice in patients with PS ≤1 experiencing hepatic IVC/VC, regardless of liver function parameters. Almost one-third of our patients were administered treatment in the last 30 days of life, potentially adversely affecting their quality of life and causing unwarranted suffering and costs. Academic clinical trials should be organized to address this pressing medical gap.

A phase Ib/II study of an anti-CD137 agonist antibody ADG106 in combination with weekly paclitaxel and dose-dense doxorubicin/cyclophosphamide.

e14507 Background: ADG106 is a fully human agonistic anti-CD137 IgG4 monoclonal antibody which modulates the tumor microenvironment and has demonstrated increased efficacy when added to chemotherapy in preclinical models. We studied the combination of ADG106 with chemotherapy. Methods: We conducted a phase Ib trial in patients with advanced solid tumors to determine the recommended phase 2 dose (RP2D) of ADG106 + weekly P (paclitaxel 80mg/m2) or ddAC (doxorubicin 60mg/m2, cyclophosphamide 600mg/m2 Q2W with pegfilgrastim), followed by a phase II trial of neoadjuvant ADG106 + weekly Px12→ADG106 + ddACx4→surgery in stage I-III HER2 negative breast cancer patients. In phase Ib, one dose of single agent ADG106 was administered followed 2 weeks later by ADG106 + ddAC (Cohort 1) or ADG106 + weekly P (Cohort 2). Dose levels (DL) of ADG106 were 50mg (DL-1), 100mg (DL1), 200mg (DL2). Serial tumor biopsies were performed at baseline, after single agent ADG106 and at disease progression in phase I, and at baseline, after single agent ADG106, after cycle 1 ADG106 + P, and at surgery in phase II for translational studies. Results: 11 patients were enrolled into Phase Ib with median 3 (range 2-11) prior lines of palliative systemic therapy. ADG106 + ddAC (n=2 at DL1) was deemed intolerable with 1 patient experiencing G4 neutropenia and the other G3 infection; thus ADG106 was not added to ddAC in phase II. No DLTs were observed in all patients receiving ADG106 + P (n=6 at DL1; n=3 at DL2); ADG106 RP2D was declared at 200mg + P. In this cohort, the most common all-grade AEs were neutropenia (n=6), peripheral neuropathy (n=6) and fatigue (n=6); significant ≥G3 AEs were infection (n=2) and G3 neutropenia (n=6). 5/11 (45%) patients in phase I achieved clinical benefit (CBR; PR=2, SD=3) which is clinically meaningful as 9/11 (82%) had prior taxane exposure. 18 of the planned 30 patients have been enrolled into Phase II (ADG106+weekly P→ddACx4→surgery); 10 have completed study treatment and 5 have undergone surgery. While on ADG106 + P, 4 patients experienced G3 adverse events (AEs): neutropenia (n=3), hypophosphatemia (n=1), fever (n=1). Most common G1-2 AEs were ALT elevation (n=4), acneiform rash (n=3) and peripheral neuropathy (n=3). While on ddAC alone, all AEs were low grade except for 1 patient who had G3 pneumonitis from Pneumocystis Jiroveci Pneumonia. 26 sets of matched tumor biopsies have been collected (9 in phase I; 17 in phase II) and will be tested for a panel of 40 markers by multiplex IHC, including CD137, PD-L1, and CD3/4/8. Conclusions: ADG106 when combined with ddAC exacerbates neutropenia and is not tolerable despite prophylactic pegfilgrastim. The RP2D of ADG106 in combination with P is 200mg and is safe and tolerable; manageable G3 neutropenia was the most common AE. There are no new safety signals thus far in Phase II. Further efficacy analyses and studies on tumor immune markers are ongoing. Clinical trial information: NCT05275777 .

Use of Oncotype vs. Breast Cancer Index (BCI) for extended endocrine therapy decisions: A single center analysis in stage IA hormone receptor positive breast cancer.

e13083 Background: Extended Endocrine Therapy (EET) for hormone receptor positive HER-2 negative early-stage breast cancer reduces late recurrence risks but raises concerns about toxicity. Biomarker tests like the Breast Cancer Index (BCI) are vital for identifying patients who could benefit from continued ET, reassuring others against unnecessary extension. This study evaluates prognostic implications for both Oncotype Dx (Recurrence score, RS) and BCI amidst concerns about added testing costs in patients with early stage, estrogen receptor (ER) positive breast cancer. Methods: This is a single institution retrospective review of Stage IA ER positive HER-2 negative breast cancer patients who underwent both Oncotype Dx and BCI testing from January 2021 to December 2023. Pearson's correlation coefficient (r) was used to assess the linear relationship between the assays (p&lt;0.05 for significance), analysis was performed with SAS software, version 9.4. Results: Fifty-eight patients with Stage IA ER positive HER-2 negative breast cancer who had both Oncotype and BCI results were identified (100% female; mean age 72.2 years [54-87]). After a median followed up of 72 months (63-75), no systemic or locoregional recurrences were reported. A low positive correlation between Oncotype and BCI was observed across the entire cohort (r=0.4058; p=0.0016). However, subgroup analysis showed no significant correlations: Oncotype &lt;11 (n=17; r=0.2415; p=0.3504), Oncotype ≤18 (n=43; r=0.0914; p=0.5600), Oncotype &lt;26 (n=51; r=0.2530; p=0.0733); Oncotype ≥26 (n=7; r=-0.5634; p=0.1878). Correlation was also not found in patients with Grade 1 tumor (n=16; r=0.3138; p=0.2365). Thirty-nine patients (67.24%) had their treatment recommendation changed based on BCI results. Side effects from ET affected 15 patients (25.86%) and included arthralgias (60%, n=9), hot flashes (26.67%, n=4), depression (13.33%, n=2), insomnia (6.67%, n=1), and others (53.3%, n=8). Twenty-two patients (37.93%) developed new osteopenia, and 6 (10.34%) new osteoporosis while on EET. Eight patients (13.79%) had ET interruption during their treatment course. Conclusions: Despite inclination towards cost-saving measures, Oncotype DX may be more useful to give prognosis in the early adjuvant period whereas BCI is more useful to evaluate late recurrence risk. Low or high Oncotype scores and tumor grade may not align with BCI findings. Considering the importance of managing toxicity against the risk of late recurrence, incorporating BCI testing can enhance EET recommendations, even for Stage I, node-negative, ER positive patients.

Frequency of dose reductions of abemaciclib in metastatic and early-stage hormone positive, HER2 negative breast cancer.

e13099 Background: Abemaciclib is a CDK4/6 inhibitor which in combination with endocrine therapy (ET) improves progression-free survival in hormone receptor (HR)-positive, HER2 negative advanced breast cancer, as well as invasive disease free-survival in high-risk early-stage breast cancer. However, abemaciclib is associated with adverse events which may limit treatment adherence. In this single-center study, we describe real-world safety outcomes of early-stage and advanced HR-positive, HER2 negative breast cancer patients prescribed abemaciclib in conjunction with ET. Specifically, we analyze the frequency of adverse events and dose reductions (DR). Methods: We conducted a retrospective study of patients treated at Scripps Clinic between 1/1/2019-1/1/2023 with HR-positive, HER2 negative breast cancer prescribed abemaciclib with ET. Primary analyses were performed to discern clinical characteristic differences between groups. Categorical variables were summarized as frequencies and compared between arms by Chi-Square tests or Fisher’s Exact Tests. All continuous variables were summarized as means and standard deviations and compared between arms by T-Tests if normally distributed or summarized as medians and compared between arms by Mann-Whitney Tests otherwise. Statistical significance was set to 0.05 and all analyses were conducted in R. Results: A total of 77 patients were analyzed including 62% in the adjuvant setting and 38% in the metastatic setting. 51% of patients required DR. Patients requiring DR were older relative to those not requiring DR (59 vs 52 years of age, p=0.019). Those requiring DR remained on abemaciclib longer relative to those without DR (509 vs 350 days, p=0.057). Among those requiring DR, there were higher rates of grades II-IV diarrhea (p&lt;0.001) and Loperamide use (p=0.083). Those requiring DR also had higher rates of neutropenia (54% vs 29%, p=0.027), abdominal cramping (39% vs 8%, p=0.002), nausea (39% vs 13%, p=0.011), and fatigue (51% vs 32%, p=0.079). Among 9 patients who expired on abemaciclib, 7 were in the metastatic setting and 1 was linked to an adverse effect from abemaciclib; none required DR (24% vs 0%, p&lt;0.001). Finally, patients in the adjuvant setting remained on abemaciclib longer relative to those in the metastatic setting (526 vs 281 days, p=0.01). 95% of patients experienced symptom improvement with DR (p&lt;0.001). Conclusions: Our study describes real-world safety outcomes of patients with HR-positive, HER2 negative breast cancer treated with abemaciclib and ET. More than half of patients required DR. Those who reduced their abemaciclib dose had improvement of clinical symptoms and remained on therapy longer. Based on our findings and given the importance of adherence in treatment efficacy, a lower starting dose of abemaciclib may be a more tolerable strategy, especially among older patients who required more DR in our study.

Nationwide real-world practice pattern and clinical data of palbociclib in patients with HR(+), HER2(-) metastatic breast cancer (KCSG BR21-15).

1068 Background: Introduction of cyclin-dependent kinase 4/6 inhibitors in hormone-receptor (HR) positive/ human epidermal growth factor-2 (HER2) negative metastatic breast cancer (MBC) have dramatically improved clinical outcomes in terms of progression-free survival (PFS) and overall survival (OS). Although PALOMA-2 trial has met its primary outcome, it showed relatively shorter OS compared to other pivotal phase III trials with ribociclib and abemaciclib. In Korea, there are limitations to use palbociclib + AI + GnRHa in premenopausal women, and bilateral salpingo-oophorectomy is necessary before starting palbocliclib based on unique approval status. We analyzed the real-world clinical outcome of letrozole + palbociclib, including distinct baseline characteristics in Korea. Methods: Between August 2016 to December 2022, 1,017 HR-positive, HER2 negative postmenopausal MBC patients treated with letrozole with palbociclib as first line treatment were enrolled from 21 tertiary institutions participating Korean Cancer Study Group (KCSG) breast cancer committee. Medical records were collected retrospectively. Primary endpoint was the PFS of letrozole + palbociclib in total patient population and the survival difference according to the method of menopause (natural menopause or bilateral salpingo-oophrectomy, BSO). The key secondary endpoint was OS, post-progression treatment pattern, overall response rate and safety. Results: Median age of the patient was 56 years (range 27~92), with median follow-up duration of 44.8 months (interquantile range 30.8~56.47). Among total patient population, 51 patients (5%) were below 40 years of age. Most patients diagnosed as recurrent breast cancer (633, 62.2%) received adjuvant tamoxifen +/- GnRHa (404, 73.5%). Median PFS and OS was 28.0 months (95% CI 25.53-32.10) and 61.6 months (95% CI 56.93-66.80). Patients who received BSO prior to palbociclib showed similar mPFS compared to natural menopause group (28.07 vs. 28.0 months) (P=0.35). Patients with primary -tamoxifen resistance showed inferior PFS compared to secondary resistance (mPFS 14.63 vs. 27.07 months, P=0.0059). ORR was 47.5% with DCR of 89.6%. Most patients experienced any grade of neutropenia (967 patients, 95.1%), 638 patients with grade 3 neutropenia (62.7%). Among 549 patients with progressive disease, 317 patients (58.1%) received second-line endocrine treatment, with everolimus + exemestane most used. In 204 patients (37.4%) who received cytotoxic chemotherapy, capecitabine was most frequently used (95, 17.3%). About 10% patients participated in clinical trials. Conclusions: To our knowledge, this is the largest country-based real-world data of 1st line palbociclib in Asia. Palbociclib showed OS over 60 months, comparable to other pivotal clinical trials. Further follow-up analysis of PFS2 and subsequent treatment is warranted.

The immunomodulatory impacts of endocrine therapy on host immunity in early-stage hormone receptor positive, HER2 negative breast cancer.

572 Background: Endocrine therapy (ET) reduces mortality in hormonally driven breast cancer (BC). The impacts of ET on the estrogen receptor are well known; however, there is limited data on the impact of ET on the host's immune system. This project aims to elucidate the potential immunomodulatory effects of ET-induced estrogen deprivation in HR+/HER2 negative early-stage breast cancer patients (pts) as well as baseline differences between BC pts and healthy controls (HC). Methods: Pts with Stage I-III HR+/HER2- BC initiating ET after completion of local regional therapy and/or chemotherapy were enrolled (NCT03719495). Whole blood, E1 (estrone) and E2 (estradiol) levels were collected at baseline (T1), 4 weeks (T2), 12 weeks (T3) and 24 weeks (T4) after ET initiation. 5 cohorts were enrolled: premenopausal and postmenopausal HCs, premenopausal pts on tamoxifen (TAM) or aromatase inhibitors (AIs) plus ovarian suppression, postmenopausal pts on AIs. Bulk RNA sequencing of whole blood was performed using NuGEN mRNA-seq on the Illumina Nova-seq platform. Differential expression analysis was performed using DESeq2 between HC and ET groups at T1, and between T1 and T4 within BC pts. The Benjamini-Hochberg method was used to adjust the P values for multiple comparisons. A curated set of 192 immune related gene signatures was used in the gene signature analysis. For each signature/module, a score was computed by taking the median of the expression values from all genes in each gene signature. CIBERSORT analysis was performed using the LM22 signature gene file and 100 permutations. Paired t-test was performed to compare T1 and T4. Results: Between 2019 and 2023, 64 pts were enrolled. Pts with missing samples or prior chemotherapy were excluded in this analysis. T1 samples of 25 pts with BC versus 14 HCs revealed marked changes in circulating immune cell (IC) composition with 537 DEGs (p value &lt; 0.05). Circulating ICs in BC pts had marked upregulation of genes associated with oxidative phosphorylation, adipogenesis, interferon alpha, reactive oxygen species compared to HCs. Immune cell composition was inferred by CIBERSORT analysis which suggests that BC pts had fewer circulating naïve B cells (p=0.048) whereas regulatory T cells (p=0.025) and activated NK cells (p=0.0039) were higher in BC pts than HCs at T1. BC pts with reductions in E1/E2 levels 6 months after ET had 77 DEGs in PBMCs between T1 and T4. Gene signature analysis shows that B cells and NK cells (p=0.0077) signatures are elevated post ET whereas a reduction of neutrophil signature (p=0.0034) was noted. Conclusions: There are significant differences in the baseline IC repertoire/activity in BC pts compared to HCs. The reduction in B cell activity/number and an increase in regulatory T cell number suggests a possible compromised immune system in BC pts. After surgery and 6 months of ET, these suppressed immune phenotypes reversed. Clinical trial information: NCT03719495 .

Is there a correlation between estrogen receptor expression level and early breast cancer survival? A retrospective study.

e12574 Background: The optimal cut-off of estrogen receptor (ER) positivity is still debatable; however, adjuvant hormonal therapy is usually given if ER expression is ≥ 1%. The present study aims to assess the clinicopathological features and survival outcomes of patients with low compared to high ER expression levels. Methods: In this retrospective, we checked non-metastatic hormonal receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer patients who presented to three hospitals in Egypt and Saudi Arabia between 2016 and 2019. Different clinicopathological factors and data on relapse were checked in patients’ medical records. These data were compared in patients with ER-Low (1–10%) vs. ER-High (&gt;10%) expression levels. Results: We included 419 patients who met the eligibility criteria for the study. Only 3.3% of patients had ER-Low. Compared to the ER-high group, the ER-low expression group was more likely to have grade 3 tumours (64.3% vs. 21.0%, p = &lt;0.0001) and PR-negative tumors (64.3% vs. 16.3%, p = &lt;0.0001). Furthermore, younger age (≤ 50 years) was more frequent in the ER-Low group compared to ER-High patients (71.4% vs. 42.5%, respectively, p = 0.032). Likewise, ER-high patients were more likely to have high ER-staining intensity (74.1% vs. 0.0%, p&lt;0.0001). Disease-free survival (DFS) was numerically improved in patients with ER-high, but without statistical significance. After adjustment of different clinicopathological prognostic factors, the DFS benefit in the ER-high group was more definite (hazard ratio (HR) = 3.59, 95%, confidence interval (CI) = 1.11–11.55, and p value = 0.032). Conclusions: A lower estrogen receptor expression level (varying from 1 to 10%) in hormone-positive early breast cancer patients is an uncommon pattern associated with more aggressive disease features at diagnosis. This group of patients had a lower DFS than those with a higher degree of estrogen receptor expression, although there was no statistically significant difference in OS.

Personalized neoadjuvant strategy in ER positive and HER2 negative breast cancer to increase BCS rate (PLATO): A prospective, multicenter, phase II clinical trial.

595 Background: Neoadjuvant therapy significantly enhances the likelihood of breast-conserving surgery (BCS) in breast cancer patients. However, in ER-positive and HER-2 negative breast cancer, the response to neoadjuvant chemotherapy (NCT) is not as good as HER-2 positive or triple-negative breast cancer. In addition, with the evolution of multi-gene assays, many patients of this subtype may not require adjuvant chemotherapy. This study explores the potential of tailored neoadjuvant treatments (NCT or endocrine therapy (NET)) guided by 70-gene assay (Mammaprint, Agendia) to improve BCS rates in ER-positive/HER-2 negative breast cancer. Methods: A prospective, multicenter cohort study was conducted across four Korean centers from 2019 to 2023. Participants were clinical stage II-IIIA, ER-positive/HER2-negative breast cancer patients deemed unsuitable for BCS. Suitability was further verified by an independent three-surgeon panel using mammography or MRI. Out of 130 screened patients, 100 were enrolled. We analyzed 90 patients, excluding 10 cases; 2 with a basal type or HER2 type result in the blueprint, 7 who refused neoadjuvant therapy, and 1 who underwent surgery at another hospital. Before initiation of therapy, each surgeon recorded a target tumor size at which the surgeon would be able to do BCS considering location of the tumor and patient’s breast size. Based on the 70-gene assay results from core needle biopsies, high-genomic-risk patients received NCT (anthracycline + cyclophosphamide for 4 cycles, followed by 4 cycles of docetaxel), while low-risk patients underwent 16 weeks of NET with letrozole (±leuprolide for premenopausal women). Results: Out of the patients, 66 (73%) were high-genomic-risk and underwent NCT, while 24 (27%) received NET. Median tumor size was 3.7cm (85.6% clinical T2 and 14.4% T3/4). The primary endpoint, achieving the pre-established target tumor size for BCS, was reached by 70.0% (95% CI: 59.4-79.2%) of patients, significantly surpassing the set goal of 50.8% (a 15% increase from historical control). The rates were 74.2% for NCT and 58.3% for NET. The actual BCS rate was 58.9% overall (63.6% for NCT and 45.8% for NET). Clinically, 5.6% exhibited complete response (CR), 74.4% partial response (PR), 18.8% stable disease (SD), and 1.1% progressive disease (PD). Pathologic complete response (pCR) was achieved in 2.2% (all in the NCT group). No severe adverse events beyond expectations were observed. No pre-treatment clinical or pathological factor was significantly predictive for the BCS conversion. Conclusions: For ER positive, HER2 negative breast cancer patients initially ineligible for BCS, the use of pre-treatment multi-gene assays to guide selective NCT or NET could substantially increase BCS rates and reduce unnecessary chemotherapy. Clinical trial information: NCT03900637 .

Comparative genomic profiling of circulating tumor DNA and paired formalin-fixed paraffin-embedded (FFPE) DNA from Indian patients with breast cancer.

e14554 Background: Breast cancer (BC) is the most frequent malignancy and a leading cause of mortality in women worldwide. Although most BCs are treated with curative intent, 30-40 % patients experience disease progression or metastatic relapse. Considering high heterogeneity of BC, mutational profiling of solid biopsy may not be adequate for informed treatment decisions in all cases. Liquid biopsy based on circulating tumor DNA (ctDNA) analysis is emerging as an equivalent and alternative to tissue biopsy in clinical settings. Though extremely critical for management of BC, liquid biopsy is not a standard of care in India. Here we compared comprehensive genomic profiles of ctDNA and paired biopsy samples to determine the efficacy of ctDNA assay in detecting actionable mutational targets. Methods: Retrospectively, genomic DNA and matched ctDNA was isolated from both FFPE and blood samples of14 BC patients. The patients were confirmative with pathological findings, having metastatic infiltrating ductal carcinoma, or triple negative breast cancers. Genome-wide HRD, TMB and MSI scores based on the OncoIndx comprehensive gene panel (CGP) was determined. OncoIndx CGP targets 1080 cancer related genes along with 47 HRR genes and 1600 MSI signature sites. Libraries were prepared using a hybridization-capture method based on custom-designed OncoIndx 1080 CGP and sequenced (depth 5500 X) on Illumina Nextseq 2000 in a pair-end mode (150 x2). Variant calling was performed using a proprietary bioinformatics pipeline iCare. Results: All patients were diagnosed with metastatic infiltrating ductal carcinoma, or triple negative breast cancers. From the patient cohort, microsatellite instability (MSI) from ctDNA showed 100% concordance with FFPE DNA while tumor mutation burden (TMB) and homologous recombination deficiency (HRD) scores showed 71.4 % and 64.2 % concordance with FFPE DNA respectively. At the individual gene mutation level, the concordance TP53, BRCA1/2, PI3K family of genes, ESR1, PTEN, ERBB2, PALB2, and BRAF genes between ctDNA and FFPE DNA was 54.7%, 92.8%, 54.7%, 78.5%, 92.8%, 100%, 100%, and 100% respectively. Many important genomic alterations including PIK3CA:p.L334H, PIK3CA:p.E81K, ESR1:p.Q375L, BRCA2:p.X3040_splice, PTEN:p.D19H were exclusive to ctDNA thereby denoting potential tumor heterogeneities which could be missed from FFPE DNA. Conclusions: Our results suggest a high correlation between ctDNA and FFPE DNA detected by OncoIndx test in metastatic or triple negative breast cancer patients of Indian ethnicity. Although not a part of standard of care, liquid biopsy could be of significant potential for management of BC in the standard clinical settings. However, a thorough investigation of cancer stage, and clinical presentations are necessary to carefully evaluate the selection of ctDNA or FFPE DNA-based genomic profiling.

CGP-based IO biomarker assessment and treatment utilization across a major US health system.

e23109 Background: Immune checkpoint inhibitors (IO) have become a powerful precision therapy option to treat advanced stage cancer with biomarkers such as PD-L1, tumor mutational burden (TMB), and microsatellite instability (MSI) associated with improved patient response rates. Despite this, many patients do not receive genomic testing for all IO biomarkers. Providence, a large US community health system, developed a pathologist-directed testing protocol where comprehensive genomic profiling (CGP) was routinely used at time of diagnosis for advanced cancer patients. Methods: Advanced cancer patients who received CGP (ProvSeq 523) and IHC testing for PD-L1 between 2019-2023 were included in the study. Patients were required to be treated at Providence and were assessed for presence of IO biomarkers and subsequent therapy selection. Real world data were curated from patient charts and genomic laboratory data by employing a novel natural-language processing (NLP) approach to accelerate abstraction. Results: The study included 2,502 patients (53% female, median age 68y, 83% white). Top 3 tumor types tested were lung (40%), colorectal (9%), and breast (8%). Overall, 58% (N = 1,455) of patients had presence of ≥1 IO biomarker, with 46% (N = 1,155) being PD-L1 positive, and 27% (N = 682) being TMB-H. In PD-L1 negative patients (N = 1,347; 54%), 300 (22%) were TMB-H and 18 (1%) were MSI-H. 53% (N = 767) of patients who harbored an actionable IO biomarker received IO-based therapy. Fewer patients with an IO biomarker received chemotherapy compared to patients without an IO biomarker (23% vs 35%, p &lt; 0.001). Patients who possessed ≥2 IO biomarkers received an IO precision therapy 68% of the time vs 47% in patients with 1 IO biomarker (p &lt; 0.001). In PD-L1 negative patients, 26% (N = 78) of TMB-H patients received IO monotherapy compared to 5% (N = 49) of TMB-L patients. Conclusions: IO biomarker presence is associated with increased precision therapy use. CGP identified many TMB-H patients for IO monotherapy that would have been missed with PD-L1 testing alone. More than half of patients eligible for IO therapy don’t receive it; ongoing analyses will evaluate the impact of pathology-directed reflex testing on IO as well as targeted therapy approaches. [Table: see text]

Characterization of remote symptom alerts generated from patient-reported outcome (PRO) symptom monitoring in a real-world breast cancer population.

e23193 Background: Women with breast cancer experience debilitating symptoms, yet the patient-reported symptom burden among patients on treatment remains largely uncharacterized. This study characterized electronic PRO (ePRO) symptom monitoring data of patients with breast cancer in real-world settings to assess differences in remote symptom alerts by clinical characteristics. Methods: We conducted a retrospective descriptive study of complete case ePRO data reported by patients at twelve US sites using Carevive PROmPT, a remote symptom monitoring platform. Participants consent to share de-identified, aggregate ePRO symptom data and sociodemographic and clinical characteristics from the electronic health record. We characterized PRO-CTCAE symptom data reported by breast cancer patients on active cancer treatment enrolled between 9/2020 and 11/2023. The PRO platform generates an algorithm-based alert if the combination of symptom severity, frequency, and interference is moderate or severe. We used descriptive statistics to characterize symptom severity and number of alerts by baseline patient-report ECOG status, age, cancer stage (Stage I-III vs. IV), and breast cancer subtype. Results: Of 646 patients, 519 (80%) generated alerts during treatment. Population characteristics were: median age 56 years-old (range 26-84), 72% White, 20% Black/African American, 62% Stage I-III, 15% HER2 positive, 47% ER and/or PR positive, HER2 negative,18% triple negative. Patients reported a total of 19,425 symptoms over a median of 12 weeks with 80% compliance rate, of which 39% resulted in alerts. Participants generated a median of 1 alert per week. About 50% of alerts occurred in the first 12 weeks of ePRO completion, with a higher proportion in Week 1-4 across all subgroups (range, 15-38%). On average, ECOG 2 or greater patients generated more alerts per week than ECOG 0-1, (mean 2.1, (SD 1.3) vs. 1.7 (SD 1.0). Younger patients ( &lt; 50 years) generated more alerts compared to those older than 50 years (87% vs. 77%). Patients with early-stage disease reported more alerts than the Stage IV group (81% vs. 78%). In the metastatic setting, triple negative patients reported a median of 3 (range 1-8) moderate/severe symptoms per week; the other subtypes reported a median of 1 (range 1-8). Conclusions: Women on breast cancer treatment reported their symptom experience with high compliance rates in the real-world setting. Nearly 40% of symptom reports generated an alert, with a higher proportion in the first month of treatment. Younger, early-stage, and metastatic triple negative patients with breast cancer reported a higher symptom burden compared to other groups. Future work will investigate symptom experience by sociodemographic and clinical characteristics to further identify patients who may benefit from more intensive symptom reporting and management.

Monitoring ctDNA dynamics in early breast cancer using a novel ultra-sensitive tumor-informed structural variant approach combining whole-genome sequencing and multiplex dPCR.

568 Background: Persistent circulating cell-free tumor DNA (ctDNA) detection during neoadjuvant treatment of early-breast cancer (EBC) indicates high-risk disease. Detection of ctDNA post-resection of EBC (molecular residual disease, MRD) indicates occult metastatic disease and impending disease relapse. For ctDNA to be integrated into EBC management, accessible and scalable diagnostic tools are required. Here, we apply a highly sensitive, personalized tumor-informed approach to ctDNA evaluation predicated on analyses of structural variants (SVs) using a novel digital PCR (dPCR) SV technology. Methods: 170 patients with EBC and eligible for neoadjuvant therapy (NAT) were recruited through the prospective SCAN-B study (NCT02306096) between Dec 2014 and Mar 2019 (25.8% TNBC, 47.1% HR+/HER2- and 24.1% HER2+). Interim results are presented for the first 46 consecutive patients (comprising 567 plasma samples) where minimum QC criteria were met (10% tumor content and 10x sequencing depth). Whole genome sequencing (WGS) was performed on tumor material and personalized multiplex dPCR assays designed tracking up to 8 SVs for use in ctDNA analyses. Plasma samples were collected at baseline, during NAT, pre- and post-surgery and at 6-monthly intervals during follow up. Clinical characteristics and recurrence outcomes were recorded. Results: ctDNA was detected at one or more timepoints prior to surgery in 43/46 (93%) patients across all breast cancer subtypes, at a median variant allele frequency (VAF) of 0.14% (range 0.0002% - 27.6%). ctDNA levels remained detectable at the end of NAT in 24% patients (11/46); 5/11 (45%) ctDNA positive patients experienced disease relapse versus 1/35 (3%) ctDNA negative patients (P=0.002, Fisher’s exact test). At one or more post-operative timepoints, ctDNA was detected in 6/6 (100%) patients who experienced clinical recurrence, with lead times up to 52 months (median 11.8 months, range 3.5 to 52 months). In 40 patients without presentation of clinical recurrence to date, ctDNA was undetectable across 285/287 (99.3%) plasma timepoints collected post-surgery. Post-operative detection of ctDNA associated with poor overall survival (OS) compared to absence of ctDNA (log-rank P&lt;0.0001). Conclusions: In this interim analysis of an ongoing prospective study in patients with EBC receiving NAT, we analyzed plasma for ctDNA using a novel tumor-informed dPCR assay tracking patient-specific SVs. ctDNA detection post-neoadjuvant therapy, prior to surgery associated with high-risk of disease relapse. Postoperative ctDNA detection was observed in 100% patients with clinical recurrence, and associated with poorer OS and long lead-times. Our data demonstrate the feasibility of SVs as an MRD analyte and provide evidence for high levels of clinical sensitivity achievable with this approach in EBC. Clinical trial information: NCT02306096 .

Results of neoadjuvant therapy for patients with triple negative breast cancer in a public hospital in Brazil (Federal District).

e12660 Background: Breast cancer is the neoplasm with the highest number of deaths among women in Brazil. Triple negative breast cancer contributes to the worsening of this condition, considering that it is more aggressive, accounting for 15% of deaths. Furthermore, more aggressive treatments and new medications have recently been added to neoadjuvant protocols, improving the complete pathological response, but with more side effects. In this way, it is predictive to understand the profile and treatment of choice for patients diagnosed with triple negative breast cancer, contributing to a better understanding of the treatment outcome, survival and quality of life in patients with this health condition. Methods: observational and cross-sectional study with retrospective data collection, in the electronic medical record of the TrakCare system. Patients diagnosed with triple-negative breast cancer between January 2020 and December 2021 and who underwent neoadjuvant treatment were included. Information was collected regarding the date of treatment, age, color/race, comorbidity, staging, type of chemotherapy used, postoperative response rate, and patient evolution during follow-up. Results: 78 patients with triple-negative breast cancer were included. The average age of patients was 56.3 years (26 – 83 years) and approximately 38.5% of patients were under 50 years of age. Around 42.3% of patients had hypertension and 33.3% were obese. Only 28.2% of patients did not have associated comorbidities. Approximately 59% of patients were staged T4 and 35.9% staged T3. Pathological complete response (cPR) was achieved in 56.4%, but progression was recorded in 13% of cases. In 88.5% of patients, the AC-T protocol was used (doxorubicin and cyclophosphamide followed by weekly paclitaxel) and 52% obtained CPR. On the other hand, only 11.5% (9 patients) used the AC-TC protocol (doxorubicin and cyclophosphamide followed by paclitaxel and carboplatin) with a CPR of 89% (p=0.016), with no record of progression or death. Conclusions: Triple negative patients were young and tended to have at least one comorbidity in addition to a highest rate of locally advanced tumor. The more aggressive protocol (AC-TC) was used less often, but has a higher rate of cRP and should be used more frequently in this scenario despite the greater complexity of these patients.

TDP-43 Is Associated with Subiculum and Cornu Ammonis 1 Hippocampal Subfield Atrophy in Primary Age-Related Tauopathy.

TAR DNA binding protein 43 (TDP-43) has been shown to be associated with whole hippocampal atrophy in primary age-related tauopathy (PART). It is currently unknown which subregions of the hippocampus are contributing to TDP-43 associated whole hippocampal atrophy in PART. To identify which specific hippocampal subfield regions are contributing to TDP-43-associated whole hippocampal atrophy in PART. A total of 115 autopsied cases from the Mayo Clinic Alzheimer Disease Research Center, Neurodegenerative Research Group, and the Mayo Clinic Study of Aging were analyzed. All cases underwent antemortem brain volumetric MRI, neuropathological assessment of the distribution of Aβ (Thal phase), and neurofibrillary tangle (Braak stage) to diagnose PART, as well as assessment of TDP-43 presence/absence in the amygdala, hippocampus and beyond. Hippocampal subfield segmentation was performed using FreeSurfer version 7.4.1. Statistical analyses using logistic regression were performed to assess for associations between TDP-43 and hippocampal subfield volumes, accounting for potential confounders. TDP-43 positive patients (n = 37, 32%), of which 15/15 were type-α, had significantly smaller whole hippocampal volumes, and smaller volumes of the body and tail of the hippocampus compared to TDP-43 negative patients. Subfield analyses revealed an association between TDP-43 and the molecular layer of hippocampal body and the body of cornu ammonis 1 (CA1), subiculum, and presubiculum regions. There was no association between TDP-43 stage and subfield volumes. Whole hippocampal volume loss linked to TDP-43 in PART is mainly due to volume loss occurring in the molecular layer, CA1, subiculum and presubiculum of the hippocampal body.