Received Adjuvant Chemotherapy Research Articles

Superficial Neurocristic FET::ETS Fusion Tumor: Expanding the Clinicopathological and Molecular Genetic Spectrum of a Recently Described Entity

Superficial neurocristic EWSR1::FLI1 fusion tumor is a very recently described, clinically indolent tumor of the skin and superficial soft tissues, which differs in essentially all ways from Ewing sarcoma, despite harboring an identical fusion event. The EWSR1 and FLI1 genes are members of the FET and ETS gene family, respectively, and very rare examples of Ewing sarcoma harbor alternative FET::ETS fusion events, such as EWSR1::ERG, FUS::FLI1, FUS::ERG, EWSR1::ETV4 and others. We report 5 new cases of this very rare entity, harboring in 3 cases alternative FET::ETS fusion events. The tumors occurred in 2 males and 3 females (median age 14 years; range 8-69 years) and presented as solitary dermal/ subcutaneous masses of the thigh, foot, shoulder, arm and back (median size 1.8 cm; range: 1-2 cm). All patients underwent wide excisions; one received adjuvant chemotherapy. Clinical follow-up on 3 patients (median: 24 months; range: 18-31 months) showed all to be without disease. Morphologically, all tumors displayed typical features of this entity as described, with nests of cytologically bland, diffusely S100 protein/SOX10-positive round cells without mitotic activity, surrounded by fibrous bands containing spindled cells with similar nuclear features. The tumors also showed membranous CD99 (4/5) and nuclear NKX2.2 (3/3) expression. RNA sequencing (4 cases) demonstrated FUS::FLI1, FUS::ERG, EWSR1::FLI1, EWSR1::ERG, and a novel FUS::ETV5. Methylation profiling (4 cases) showed all to cluster with previously reported superficial neurocristic EWSR1::FLI1 fusion tumors and apart from conventional and “adamantinoma-like” Ewing sarcoma.Our findings confirm the distinctive clinicopathological features of this very rare, recently described entity and expand its molecular genetic spectrum. Reflecting these findings, we propose modifying the name of this entity to “superficial neurocristic FET::ETS fusion tumor”.

Chemotherapy affects the development of pathological scarring after general thoracic surgery in children.

Globally, a great number of children have been suffering from physical dysfunction and psychological stress due to uncontrollable scar growth and a lack of effective modalities. Despite chemotherapy's established role as a primary treatment for pathological scarring in adults, its efficacy in preventing or minimizing scar formation in paediatric patients remains underexplored. This retrospective cohort study aimed to refine the relevant clinical evidence and investigate the effect of chemotherapy on pathological scars in children. In this single-centre retrospective cohort study, the data of children aged ≤18 years who underwent thoracic surgery at the Children's Hospital of Fudan University between 1 January 2018, and 31 December 2021 were assessed. The primary outcome was pathological scarring, and the secondary outcomes were subjective symptoms accompanying pathological scarring, such as pain and itching. To mitigate indication bias, analysis was performed by inverse probability weighting (IPTW) log-binomial regression models. The cohort comprised 102 children, among whom 36 received adjuvant chemotherapy perioperatively, while 66 did not. Under the IPTW model, a statistically significant difference in pathological scarring incidence was observed between the chemotherapy and non-chemotherapy groups (16.7% vs. 29.4%, p = 0.027). And the children received chemotherapy post-operatively had a lower relative risk of pathological scarring, compared with those received chemotherapy both before and after surgery (19.8% vs. 28.8%). Adjuvant chemotherapy treatment after surgery may reduce the incidence of post-operative pathological scarring in children.

Treatment patterns of adenoid cystic carcinoma of the breast: A systematic review.

e13147 Background: Adenoid cystic carcinoma of breast (ACC-B) is a rare subtype of breast cancer (BC) accounting for 0.1% of all BCs. It shares histologic features with ACCs arising in the salivary glands and other locations. Given the hormone receptor (HR) negative phenotype [negative expression of the estrogen receptor (ER), progesterone receptor (PR)], some clinicians treat ACC-B as a basal subtype of BC, which is predominantly treated with chemotherapy. However, ACC-B has a more indolent and favorable clinical behavior. There are no established treatment guidelines for ACC-B. We conducted a systematic review of the literature on the treatment patterns for ACC-B. Methods: We followed the PRISMA criteria using the database in Cochrane, Embase, PubMed, Scopus, and Web of Science. The Covidence software was used for screening and data extraction. Eligible studies discussed the management of stage I-III ACC-B from 1960 to 2022. Individual patient (pt) demographics, tumor characteristics, treatment and outcomes were collected, when available. Results: The database search found 2864 studies, of which 187 articles met the inclusion criteria in the study protocol. Given the rarity of this subtype of BC, most studies were case reports (n=104). A total of 4370 pts with a median age of 57 years were eligible for analysis. Information on ER, PR and HER2 status was not available for all cases. For the cases in which this was reported, most were ER and/or PR negative (76% ER negative and 83% PR negative). Surgery was the primary treatment reported for 3984 pts. A total of 21.5% underwent mastectomy, 40.7% lumpectomy and 37.7% were treated with other modalities of surgery. In the group of patients for which information was available regarding the receipt of systemic therapy (n=3147), 82% did not receive neoadjuvant or adjuvant chemotherapy. Metastatic disease was reported to have developed in 2.2% of the total patients (n=98). Median time to recurrence was 31 months (0-460) with a median overall survival of 134 months (1-462). The most common site of metastases were the lungs (60%). Among the patients who developed metastatic disease and for whom initial treatment information was available; radiation was given to 32 pts, 26 received adjuvant chemotherapy and 15 received both radiation and chemotherapy. No patients that developed metastatic disease received neoadjuvant chemotherapy. Conclusions: Our results suggests that ACC-B has a clinical behavior different from basal subtype of BC. In our review, only 2.2% of pts relapsed with metastatic disease, even though most of the pts did not receive prior systemic therapy. We need to better understand the genomic landscape of ACC-B, to identify pts who may be at risk for recurrence and develop specific guidelines to treat this rare type of BC.

Is neoadjuvant chemotherapy necessary for T2N0-1M0 hormone receptor-positive/HER2-negative breast cancer patients undergoing breast-conserving surgery?

IntroductionFor HR-positive/HER2-negative patients who can undergo breast-conserving surgery (BCS) but have a tumor size of 2–5 cm or 1–3 lymph node metastases, neoadjuvant chemotherapy (NAC) is still controversial.MethodsPatients with T2N0-1M0 HR-positive/HER2-negative BC who underwent BCS between 2010 and 2017 were selected from the SEER database. Propensity score matching (PSM) was used to minimize the influence of confounding factors. The overall survival (OS) and breast cancer-specific survival (BCSS) of patients were estimated by Kaplan‒Meier curves and Cox proportional hazard models. Independent prognostic factors were included to construct a nomogram prediction model.ResultsA total of 6475 BC patients were enrolled, of whom 553 received NAC and 5922 received adjuvant chemotherapy (AC). In the T2N0-1M0 population and T2N1M0 subgroup, AC patients before PSM had better OS and BCSS than NAC patients. After PSM, there was no significant difference in OS or BCSS between the two groups. However, in the T2N0M0 subgroup, there was no difference in survival between the AC and NAC groups before and after PSM. Stratified analysis revealed that for complete response (CR) patients, survival was roughly equivalent between the NAC and AC groups. However, the survival of no response (NR) and partial response (PR) patients was significantly worse than that of AC patients. Cox analysis revealed that radiotherapy after BCS was an independent protective factor for OS. NAC is an independent risk factor for NR and PR patients. The nomogram has good prediction efficiency.ConclusionNAC before BCS is not necessary for T2N0-1M0 HR-positive/HER2-negative BC patients.

Abstract PO2-17-10: Metaplastic breast cancer: description of 16 cases treated at a reference center and review of the literature

Abstract Background: Metaplastic breast carcinomas (MBC) are very rare and represent less than 1% of all invasive breast carcinomas. It is a heterogeneous neoplasm characterized by a mixture of adenocarcinoma with other histological elements such as squamous cells, spindle cells or other mesenchymal differentiation. Most MBC are hormone receptor and Her2 negative and tend to have a worse prognosis when compared to triple negative carcinomas. Clinically, they manifest as a rapidly growing palpable mass, without necessarily involving lymph nodes. According to the nomenclature of the WHO Classification of Tumors of the Breast (2012), tumors were classified into 4 variants: spindle cell, squamous cell, mesenchymal and mixed. Since publications on MBC are scarce in the literature, we studied the cases that were attended at Hospital Pérola Byington in the period 2010-2021. Methods: A retrospective study was carried out by reviewing the medical records of patients treated at the Reference Center for Women's Health - Pérola Byington Hospital, São Paulo, Brazil. Patients with breast cancer, with anatomopathological result confirming the diagnosis of metaplastic carcinoma were reviewed. Clinical data and histopathological characteristics were evaluated, as well as the type of treatment performed and the evolution. Results: A total of 16 female patients diagnosed with MBC were included. The median age was 56 years (ranging from 34 to 88). The mean initial size observed was 7 cm (ranging from 2 to 20 cm) and 94% of patients presented with a palpable mass. The initial clinical staging were I (12%), II (32%), III (50%) and IV (6%). The most common histological subtype was spindle cell (50%), of which 2 were squamous (12%), 3 mesenchymal (20%), 1 mixed spindle/squamous (6%) and 2 were not classified. Regarding immunohistochemistry, 14 patients (88%) had hormone negative and Her2 negative (triple negative). Of the 16 cases, 8 underwent mastectomy and 6 partial mastectomiy and 2 patients did not undergo surgical treatment because they died despite treatment with neoadjuvant chemotherapy. All operated patients underwent sentinel lymph node biopsy or axillary dissection and 85% of them did not have axillary lymph node involvement. Radiotherapy was indicated in 13 patients. Chemotherapy was performed in 10 patients, 6 of which were neoadjuvant (since the tumors were not resectable) and 4 received adjuvant chemotherapy. Of the 6 patients that underwent neoadjuvant chemotherapy, 2 had disease progression, 3 partial response and 1 complete pathological response. During follow-up, 4 (25%) evolved with locoregional recurrence and 5 (31%) with metastatic disease. Of these women, 44% (7) are still alive. We also found that 6 of the 16 cases (37%) did not receive a diagnosis of MBC in the initial biopsy, requiring revision, a new biopsy or study of the surgical specimen for confirmation. Conclusion: As verified in the literature, MBC is a very rare histological type and corresponded to 0.2% of all cases of breast cancer in the period described above. Most patients have an advanced tumor at the time of diagnosis and little axillary involvement. The most common histological classification is the spindle cell variant and almost all tumors are triple negative. The CMM has an aggressive behavior and little response to chemotherapy treatments. Therefore, radical surgical treatments are preferred. Due to the rarity of this entity there is little data published in the international literature. Citation Format: Andre Mattar, Marcelo Antonini, Marina Diogenes, Andressa Amorim, Francisco Pimentel Cavalcante, Luiz Henrique Gebrim. Metaplastic breast cancer: description of 16 cases treated at a reference center and review of the literature [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-17-10.

An Overview of the Bench to Bedside Models of Breast Cancer in the Era of Cancer Immunotherapy

Lymphoma involves abnormal lymphoid cell growth, often originating in lymphatic tissue, but in this case series non-Hodking's lymphoma is visible in the extra-nodal region. This research explores different lymphoma cases, focusing on diverse presentations and utilizing modern imaging for evaluation. Four cases are detailed, involving an 18-year-old woman with tonsillar lymphoma, a 69-year-old man with ocular lymphoma, a 38-year-old lady with abdominal lymphoma, and a 30-year-old man with gastric lymphoma. All cases received adjuvant chemotherapy (RCHOP), leading to significant symptom relief after four cycles. One of the barriers to novel treatment developments within breast cancer is the ability to prove efficacy in the preclinical setting before moving on to clinical trials. Preclinical models range from single cell monolayers to more sophisticated humanised PDXs systems each with their set of advantages and limitations. Modelling the immune environment in cold tumours, such as breast cancer can also be challenging as are currently no clearly defined markers that can stratify patients based on treatment response. Immune checkpoints receptors such as PD-L1 may not show predictive outcomes in this tumour type. Furthermore, the heterogeneity of breast cancer may be difficult to recapitulate at the bench side. In this review, we provide an overview of the available in vitro, in vivo and ex vivo models of breast cancer with consideration of how these may extrapolated to the investigation of the role of the immune system and immunotherapy developments in breast cancer.

Real-life experiences and barriers to adjuvant chemotherapy in Saudi patients with advanced stage II and stage III colon cancer.

Colorectal cancer is the most common malignancy in Saudi males and third most common in females. Patients with locally advanced colon cancer may eventually develop metastatic disease if not treated promptly and according to guidelines. The recent National Comprehensive Cancer Network guideline recommends tumor resection followed by adjuvant chemotherapy for stage III and high-risk stage II tumors. Therefore, the objective of this study was to characterize patients with locally advanced colon cancer and identify factors associated with the use of adjuvant chemotherapy and the addition of oxaliplatin in locally advanced colon cancer patients. All patients diagnosed with locally advanced colon cancer at National Guard Health Affairs (NGHA) during 2016-2021 were investigated. Patients' characteristics were compared using Chi-square and Fisher exact test, whereas predictors of adjuvant chemotherapy/Oxaliplatin use were identified using univariate and multivariate logistic regression. Out of 222 patients diagnosed with locally advanced colon cancer, 133 received adjuvant chemotherapy. Factors associated with adjuvant chemotherapy administration were age and smoking status. In the multivariable analysis, older patients were less likely to receive oxaliplatin than younger patients. Stage III patients diagnosed during 2019-2021 had 5.61 times higher odds of receiving oxaliplatin. The findings of this study show that older patients and smokers are less likely to be treated with adjuvant chemotherapy. Moreover, age as well as diagnosis year were important determinants of oxaliplatin administration in stage III locally advanced colon cancer patients.

Primary Intraosseous Synovial Sarcoma: Experience from a Tertiary Cancer Center

Introduction Primary intraosseous synovial sarcoma (PISS) is a rare cancer of the bone, with few reported cases across literature. Data from our institute reveals seven indigenous cases. This study aims to evaluate these PISS diagnoses, and to further investigate any histopathological findings and prognostic factors associated with patient survival. Materials and Methods Data from patients diagnosed with PISS at the institute were obtained from January 1995 to December 2016, in the form of a retrospective study. Patient demographics, pathology locations, histological findings, surgical margins, and treatment modalities were audited as variables that can impact patient survival. Results This research identified seven cases which fulfilled the diagnostic criteria and were subsequently classified as PISS of the bone. There were five men and two women among the cases, with ages ranging from 16 to 46 years, with a mean of 29.6 years. The study found that the lower limb was the most affected site in PISS, followed by the pelvis. Limb salvage was performed in six patients and one patient underwent amputation. Of these patients, six received adjuvant chemotherapy and four received adjuvant radiation as per institution guidelines. The study found that the 5-year disease-free and overall survival rate was 80 and 61%, respectively. Conclusion PISS is a rare malignancy with limited cases in literature, and hence, there is no evidence for a standardized management protocol. The survival rates were similar between soft tissue and intraosseous synovial sarcoma among the case series.

A single-institution analysis of a rare variant of pancreatic neoplasm-osteoclastic giant cell tumor.

e16315 Background: Pancreatic osteoclastic giant cell tumor (OGCT) is a rare variant (<1% cases) of pancreatic neoplasm. Due to its rarity, prospective studies on management are limited. The prognosis and molecular characteristics may differ from pancreatic adenocarcinoma. Methods: We analyzed demographics, clinical features, treatment modalities, and outcomes of overall survival (OS) and progression-free survival (PFS) in patients with pancreatic OGCT at our institution from 2005-2022. Results: We identified 8 OGCT patients with a median age of 67, of whom 7 had locoregional disease (resectable- 5, borderline resectable- 1, locally advanced-1), and 1 had denovo metastatic disease at diagnosis. The borderline resectable and locally advanced patients eventually developed metastatic disease. The majority of patients were male (n=5), Caucasian (n=7), former smokers (n=5), had no significant alcohol use (n=8) and had no pre-existing pancreatitis (n=8). 4 of the 5 resectable patients had surgery, and 2 received adjuvant chemotherapy. The median OS was 54 months for locoregional disease (n=5) vs.16 months for metastatic disease (denovo metastatic and progression to metastatic disease, n=3). The median OS was 54 months for surgical resection (n=4) vs. 25 months for those without surgical resection (n=4) based on quartile computations from the Kaplan-Meier survival curve. Conclusions: Our patients had a longer OS than the previously reported OS of less than 12 months for all stages of pancreatic OGCT. There was no progression in resectable patients, indicating an indolent disease with an overall good prognosis. Patients with locoregional disease or those who underwent surgical resection had longer OS, but due to the small sample size and censored patient survival times (i.e., patients still alive), the statistical significance of this trend could not be calculated. Studies are required to understand tumor biology and determine the optimal multidisciplinary treatment. [Table: see text]

Systematic review of breast implant associated squamous cell carcinoma.

e12508 Background: Breast augmentation is a cosmetic procedure with low rates of complication like bleeding, infection, implant rupture, and capsular contracture. However, rare cases of breast implant-associated (BIA) malignancies, including anaplastic large cell lymphoma (ALCL) and squamous cell carcinoma (SCC), have been reported. BIA-SCC is rarer than ALCL and current literature is limited to case reports. In 2022, the American Society of Plastic Surgeons (ASPS) issued a BIA-SCC summary statement based on 16 reported cases in response to an FDA safety communication. The aim of this study is to review published cases of BIA-SCC and present clinical and outcome data systematically. Methods: We conducted a literature search in English to identify studies reporting BIA-SCC from inception to October 2022. Patient characteristics and relevant outcomes were gathered from the studies. The mortality rates at 6 and 12 months were calculated as the inverse of the Kaplan-Meier survival estimate and presented with a 95% confidence interval (CI). Results: 14 articles and 18 cases of BIA-SCC were identified through a literature search. A rising trend in case reporting was observed, with 4 cases in the 1990s and 14 cases since 2010. The mean patient age was 56 years (range 40-81), and the mean time from breast augmentation to symptom appearance was 21 years (range 10-35). Most patients (13/18, 72%) underwent the procedure for cosmetic reasons. Out of 17 cases with available implant information, 11 cases had silicone based implants and 6 cases saline implants. Implant surface information was available in 5 cases, 4 smooth and 1 textured. 16 patients had swelling of the breast and 15 patients had breast pain at presentation of BIA-SCC. All patients had their implants removed and 10 underwent mastectomy after a diagnosis of SCC. Of the 12 cases with available treatment information, 7 received adjuvant chemotherapy and/or radiotherapy, 2 received neoadjuvant chemotherapy, and 3 did not receive perioperative chemotherapy or radiotherapy. Follow-up data was available for 10 cases. The 6-month and 12-month mortality rates were 11.1% (95% CI: 0.5% to 40.6%) and 23.8% (95% CI: 2.8% to 56.1%). Conclusions: The estimated 6-month mortality rate of 11% (95% CI: 0.5%-40.6%) should be interpreted cautiously due to the small sample size. It is lower than the rate reported by ASPS (44%), but the reason for this difference cannot be accurately explained as the methodology for determining then mortality rate is not provided in the ASPS statement. This study provides a valuable systematic review of a rare and poorly understood condition with a poor prognosis. Monitoring and sharing information is crucial to improve detection and management of BIA-SCC. [Table: see text]

Long-term longitudinal patterns of patient-reported quality of life (QOL) after breast cancer (BC) to inform the implementation of personalized pathways of care.

12081 Background: There is substantial inter individual variability in long-term trajectories of patient-reported quality of life (QOL) after early BC. Previous work focused on a selected group of patients (pts) treated with chemotherapy (CT) identified a cluster of pts with upfront poor QOL but also pts with severe, persistent post-chemotherapy QOL deterioration. We aimed to expand this work to a non-selected group of pts with early BC to identify latent clusters of pts at risk for QOL deterioration, and to assess the relationship of actionable host factors and health behaviors with trajectory group membership. Methods: We performed a detailed longitudinal analysis of QOL using a large ongoing national prospective clinical cohort (CANcer TOxicity, NCT01993498) of pts with stage I-III BC treated from 2012-2018. QOL (EORTC QLQ-C30 summary score) was assessed at diagnosis (dx, baseline) and year 1, 2, 4 and 6 post-dx. Baseline clinical, sociodemographic, behavioral, tumor-related, and treatment-related characteristics were available. Trajectories of QOL and group membership associations were identified by iterative estimations of group-based trajectory models and multivariable multinomial logistic regression, respectively, among the whole cohort. Results: Among 10,792 pts, 5,695 received adjuvant CT and 8,805 received adjuvant endocrine therapy (ET). Four QOL trajectory groups were identified: excellent (N = 4,934, 45.8%), very good (N = 3,596, 33.3%), deteriorating (N = 1,745, 16.1%), and poor (N = 517, 4.8%). The deteriorating trajectory group reported fairly good baseline QOL (73.3 [95% CI], [72.4 to 74.2]), which significantly worsened at year-1 (63.0 [62.1 to 63.9]) and never recovered to pretreatment values through year-6 (64.7 [63.3 to 66.0]) post diagnosis. Factors associated with membership to the deteriorating group included younger age (aOR, 10-years decrement 1.10 [95% CI, 1.05 to 1.16]), overweight or obesity (aOR v lean, 1.90 [95% CI, 1.60 to 2.25]; 1.25 [95% CI, 1.07 to 1.46], respectively), physical inactivity (aOR v active, 1.13 [95% CI, 1.04 to 1.35]), former smoking behavior (aOR v never, 2.14 [95% CI, 1.80 to 2.54]), Charlson comorbidity score ≥1 (aOR v 0, 1.56 [95% CI, 1.33 to 1.83]), lower household income ( < 3000 EU/month) (aOR v ≥3000, 1.50 [95% CI, 1.30 to 1.72]), receipt of adjuvant CT (aOR v no, 1.35 [95% CI, 1.14 to 1.59]) and receipt of adjuvant ET (aOR v no, 1.46 [95% CI, 1.22 to 1.75]). Conclusions: This study will help identify latent clusters of pts who are at risk of persistent QOL deterioration after BC, independently of receipt of CT. Trajectory clustering can help facilitate the creation of personalized pathways that may include early addressal of actionable factors, including referral to social work and healthy lifestyle interventions. Clinical trial information: NCT01993498 .

Role of adjuvant chemotherapy on recurrence and survival in patients with resected ampulla of Vater carcinoma

Owing to rarity of disease and lack of prospective studies, data supporting the role of adjuvant chemotherapy in ampulla of Vater (AoV) carcinoma is limited. To evaluate whether adjuvant chemotherapy cases for AoV carcinoma had better disease-free survival (DFS) rates than cases of observation following curative surgery. We retrospectively analyzed the association between adjuvant chemotherapy and DFS and overall survival (OS) in patients with stage IB-III AoV carcinoma who underwent curative surgical resection. Fluorouracil-based adjuvant chemotherapy was administered after surgery at the discretion of the physician. Adjusted multivariate regression models were used to evaluate the association between adjuvant chemotherapy and survival outcomes. Of the total 104 patients who underwent curative surgery, 52 received adjuvant chemotherapy. Multivariate analysis revealed that higher histologic grade [hazard ratio (HR) = 2.24, P = 0.046], advanced tumor stage (HR = 1.85, P = 0.030), and vascular invasion (HR = 2.14, P = 0.010) were associated with shorter DFS. Adjuvant chemotherapy improved DFS compared to the observation group (HR = 0.50, P = 0.015) and tended to be associated with a longer OS, although the difference was not statistically significant (HR = 0.58, P = 0.098). Among patients with resected AoV carcinoma, the adjuvant chemotherapy group was not associated with a significant survival benefit compared to the observation group. However, on multivariate analysis adjusting for prognostic factors, adjuvant chemotherapy following surgery was an independent prognostic factor for DFS in patients with resected AoV carcinoma. Further studies are needed to investigate the effectiveness of adjuvant chemotherapy according to histologic phenotype.

Abstract P3-05-59: ER+ HER2-negative mBRCA1/2 carriers breast cancer patients (n=81): Clinical outcomes and molecular characterization via the 21-gene Breast Recurrence Score (RS) test vs the general RS-tested population (799,986 samples)

Abstract Background: The RS assay is a validated prognosticator/predictor of chemotherapy (CT) benefit in ER+ HER2-negative early-stage breast cancer (BC). It is offered to pts irrespective of BRCA1/2 status. We compared RS results, single-gene expression and gene group scores, between pts with germline BRCA1/2 mutations and the general BC pt population undergoing RS testing. Treatments/outcomes in the mBRCA1/2 cohort were also examined. Methods: This real-life retrospective cohort study included consecutive ER+ HER2-negative mBRCA1/2 female carriers BC pts who had RS testing in 2004-2015. RS and gene expression data were compared to a previously described commercial use database (DB) (J Surg Oncol. 2020;122:611). Chi-square test and 1-sample t-test were used to compare RS distribution and single gene/gene group scores, respectively, between the cohort and the DB. Independent sample t-test was used to compare gene expression/gene group scores across pt subgroups within the mBRCA1/2 cohort. Fisher’s test/logistic regression were used to identify variables associated with distant recurrence in the mBRCA1/2 cohort. Results: The analysis included 81 pts in the mBRCA1/2 cohort and 799,986 BC samples in the DB. Age at diagnosis was younger in the mBRCA1/2 pts vs the DB (median [IQR], 56 [47-61.5] vs 60 [51-67] yrs; P<.001). In mBRCA1 and mBRCA2 pts (32 and 48 pts, respectively; for 1 pt, the BRCA gene involved was unknown), RS distribution shifted towards the high RS category when compared to the DB (Table). Comparing single-gene expression and gene group scores in mBRCA1 pts vs the DB, revealed statistically significant differences in 12 of the 16 cancer genes in the RS assay, and in 2 gene group scores, all in a direction contributing to higher RS results. Similar analysis with mBRCA2 pts, revealed significant differences in expression of 10 genes and 3 gene group scores, all in a direction contributing to higher RS results. The only statistically significant difference in gene expression between the mBRCA1 and mBRCA2 pts was in the ESR (higher in mBRCA2 pts; P=.0407) and MYBL2 gene (higher in mBRCA1 pts; P=.0365) (Table). Of the 32 mBRCA1 pts, 18 (56%) received CT (RS 0-25, 1/14 [7%]; RS 26-100, 17/18 [94%]; treatment information was unavailable for 1 pt). Of the 48 mBRCA2 pts, 19 (40%) received CT (RS 0-25, 5/27 [19%]; RS 26-100, 14/21 [67%]). With a median (IQR) follow up of 8.2 (5.6-9.7) yrs from diagnosis, 9 pts had distant recurrence (1 mBRCA1 pt, 8 mBRCA2 pts). Their median RS result was 25 (range, 16-41), and 4 received adjuvant CT. No statistically significant differences were observed between these 9 pts and the 72 non-recurring pts in terms of pt/disease characteristics and CT treatment. A trend towards significance was observed with respect to the BRCA gene involved (recurrence rate of 3.1% in mBRCA1 pts vs 16.7% in mBRCA2 pts, P=.078). A statistically significant association was found between the proliferation and invasion gene group scores and the odds of having distant recurrence (proliferation group score: odds ratio [OR], 23.60 [95% CI, 1.4-397], P=.0281; invasion group score: OR, 5.1 [95% CI, 1.1-23], P=.0339). The ER and HER2 gene groups scores were not associated with distant recurrence. Conclusions: Both mBRCA1 and mBRCA2 carriers are characterized by higher RS results that stem from a distinct gene expression profile of most genes in the RS assay. Single Gene Expression and Gene Group Scores vs the Commercial Use DB Citation Format: Rinat Yerushalmi, Adi Pomerantz, Ron Lewin, Shani Paluch-Shimon, Lior Soussan-Gutman, Frederick Baehner, Hillary Voet, Avital Bareket-Samish, Inbal Kedar, Yael Goldberg, Tamar Peretz-Yablonski, Luna Kadouri. ER+ HER2-negative mBRCA1/2 carriers breast cancer patients (n=81): Clinical outcomes and molecular characterization via the 21-gene Breast Recurrence Score (RS) test vs the general RS-tested population (799,986 samples) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-05-59.

Clinical Outcome in Patients With Early-Stage Small Cell Lung Cancer Treated With Surgery or Radiation in the Absence of Prophylactic Cranial Irradiation: A Single-Center Retrospective Study

As screening chest computed tomography for patients at high risk for cancer has become more widely accepted, increasing numbers of patients with early-stage small cell lung cancer (SCLC) are being diagnosed. Although surgery is an accepted option for patients with early-stage SCLC, for patients who decline or cannot undergo surgery, stereotactic body radiation treatment (SBRT) is an alternative. Although prophylactic cranial irradiation (PCI) improves survival in patients with limited-stage SCLC, PCI for early-stage SCLC (stage T1-T2) has not been explored. This study defines survival and recurrence patterns in patients with early-stage SCLC who were treated with surgery or SBRT in the absence of PCI. In this single-institution retrospective study, 14 patients diagnosed with early-stage SCLC (stage T1-T2) between July 2015 and May 2021 at a single tertiary care hospital were treated with SBRT or surgery with no PCI. Primary outcomes were locoregional cancer recurrence, distant recurrence, recurrence-free survival, and overall survival. The secondary outcome was development of brain metastasis. Analyses included Cox regression, Kaplan-Meier survival, and log-rank tests. A total of 14 patients (5 women and 9 men) were included in the study: 9 with stage T1 and 5 with stage T2 SCLC. Six patients (43%) received SBRT and 8 (57%) had surgical treatment. All patients except 1 received adjuvant chemotherapy. Median follow-up was 14.3 months (range, 2.4-64.4 months), and the median age at diagnosis was 71.5 years (range, 54-81 years). Cox regression and log-rank tests showed no significant differences in any outcomes between the surgery and SBRT groups, and no patients developed brain metastases during the study period. Data are lacking regarding the benefit of PCI in early-stage SCLC. Although the sample size in this study was too small to draw any conclusions, the findings add to the ongoing dialogue regarding the importance of PCI in this patient population. No difference was identified in survival and cancer recurrence in patients who received either surgery or SBRT in the absence of PCI.

Collecting Duct Carcinoma of the Kidney

Purpose: Collecting duct carcinoma of the kidney (CDC) is an aggressive subtype of renal cell carcinoma with a dismal prognosis. The available knowledge concerning optimal management is still unclear. We report the largest single-institutional experience in the management of CDC. Materials and Methods: All the cases of CDC which were diagnosed at our center following a radical or partial nephrectomy in the past 15 years were included. Treatment details, radiological features, and histological features were reviewed. Descriptive statistics were used to show the clinicopathological profile and management of these patients, and Kaplan–Meier overall survival (OS) estimate was calculated. Results: Eighteen patients who were diagnosed and underwent the primary intervention at our center were included. The median age of patients was 40 years, with a male-to-female ratio of 5:1. Typical histopathological features included high-grade nuclear features, stromal desmoplasia, and tubular architecture. Surgery was the primary modality of treatment. Five (28%) patients who had metastases received adjuvant therapy, three received interferon-alpha therapy, and two received adjuvant chemotherapy with gemcitabine and cisplatin. The median follow-up was 19 months (range: 3–46 months). Kaplan–Meier OS estimate was 68% at 1 year and 48% at 3 years. Conclusion: CDC of the kidney often presents at an advanced stage, and has a poor prognosis. Survival remains poor despite surgery and adjuvant therapy.

"Exploring Diverse Presentations of extra nodal Non-Hodgkin's Lymphoma: A Comprehensive Study of Clinical Staging, Treatment, and Controversies.

Lymphoma involves abnormal lymphoid cell growth, often originating in lymphatic tissue, but in this case series non-Hodking's lymphoma is visible in the extra-nodal region. This research explores different lymphoma cases, focusing on diverse presentations and utilizing modern imaging for evaluation. Four cases are detailed, involving an 18-year-old woman with tonsillar lymphoma, a 69-year-old man with ocular lymphoma, a 38-year-old lady with abdominal lymphoma, and a 30-year-old man with gastric lymphoma. All cases received adjuvant chemotherapy (RCHOP), leading to significant symptom relief after four cycles. The discussion highlights the debate surrounding the classification of primary extranodal non-Hodgkin's lymphoma (NHL), challenging the existing Ann Arbor classification's applicability. A major challenge in managing primary extranodal lymphomas is the absence of specific treatment guidelines. Evaluation criteria, defining complete response as the disappearance of all evidence of the disease, guided the study. In conclusion, this case series underscores the importance of a multidisciplinary approach in diagnosing, staging, and managing non-Hodgkin’s lymphoma. Despite challenges in defining and treating primary extranodal non-Hodgkin’s lymphoma, the study demonstrates the effectiveness of adjuvant chemotherapy in providing relief, as all the cases revealed recovery after 4 continuous cycles of chemotherapy.

523. RISK FACTORS ASSOCIATED WITH NOT RECEIVING ADJUVANT CHEMOTHERAPY FOR LOCALLY ADVANCED ESOPHAGOGASTRIC ADENOCARCINOMA

Abstract Perioperative chemotherapy is standard of care in the curative treatment of locally advanced esophagogastric adenocarcinoma in the UK. Previously used MAGIC triplet is becoming less frequently used in favor of superior FLOT quadruplet. There is however large number of patients who don't undergo adjuvant component of both of these perioperative regimens. This study aimed to investigate factors which are associated with not receiving adjuvant chemotherapy after neoadjuvant chemotherapy followed by surgical resection for esophagogastric adenocarcinoma. All patient receiving neoadjuvant chemotherapy for esophagogastric adenocarcinoma followed by curative surgery during 2010 till 2019 were identified from prospectively maintained single institution database. Patients who died in-hospital or within 90 days of surgery were excluded from analyses. Risk factors which could be associated with receiving/not receiving adjuvant component were studied. Mann U Whitney and chi-square test were used as appropriate. Multivariable logistic regression was carried out to identify risk factors independently predictive of not receiving adjuvant chemotherapy. Analyses included 624 patients of whom 273 received adjuvant chemotherapy (44%). This included ECX/ECF in 233 patients, EOX in 5 patients, FLOT in 22 patients and other/unknown regimens in 13 patients. Age, Charlson comorbidity index, return to theatre, severe postoperative complications (Clavien-Dindo grade III+) and R1 resection were associated with not receiving adjuvant chemotherapy (p 0.005, p 0.006, p 0.026, p 0.043, p 0.004 respectively). Statistically significant variables were entered into multivariable logistic regression model. Only R1 resection was independently associated with not receiving adjuvant component (OR 0.18, p 0.007). This study confirms that only less than half of patients who undergo neoadjuvant chemotherapy followed by surgery with curative intent receive adjuvant chemotherapy. Reasons for this are multifactorial but age, comorbidities, severe complications and positive longitudinal margin might play important role. These results also highlight the importance of prevention, early detection and appropriate management of postoperative complications.

414P Long-term follow-up of the randomized trial of the conventional technique versus the no-touch isolation technique for primary tumor resection in patients with colon cancer ( JCOG1006)

The no-touch isolation technique (No Touch) aims to reduce cancer cells from the primary tumor site to the liver and other organs by preceding ligation of blood vessels that feed the primary tumor. We conducted a phase III trial (JCOG1006) to confirm the superiority of No Touch in patients with cT3/T4 colon cancer, with a primary endpoint of disease-free survival (DFS). The planned primary analysis at 3 years after the last patient-in failed to confirm the superiority of No Touch compared with conventional technique (Conventional). The present study aimed to compare No Touch and Conventional using long-term follow-up data with 6 years after the last patient-in. Eligibility criteria included histologically proven colon cancer; tumor located in the cecum, ascending, transverse, descending, sigmoid or rectosigmoid colon; clinical T3 or T4, N0-2, M0; patients aged 20-80 years. Patients were randomized preoperatively to either Conventional arm or No Touch arm. Operation was performed by open surgery. Patients with pathological stage III received adjuvant chemotherapy with capecitabine. Planned sample size was 850 to detect a hazard ratio (HR) of 0.732 in DFS with one-sided alpha of 5% and power of 80%. A total of 853 patients were randomized (Conventional: 427, No Touch: 426) between January 2011 and November 2015. The 6-year DFS were 70.3% and 69.4% in the Conventional arm and No Touch arm, respectively. The HR was 1.030(95% CI 0.813-1.304); therefore, the superiority of No Touch was not confirmed (p=0.60). The 6-year overall survival (OS), 6-year relapse-free survival (RFS) and 6-year liver-relapse-free survival (LRFS) are shown in the table.Table: 414PConventional (95% CI)No touch (95% CI)HR (95% CI)6-year DFS70.3% (65.7-74.4%)69.4% (64.8-73.6%)1.030 (0.813-1.304)6-year OS89.4% (86.0-92.0%)86.6% (82.9-89.5%)1.276 (0.902-1.807)6-year RFS78.9% (74.7-82.5%)75.0% (70.6-78.8%)1.209 (0.920-1.589)6-year LRFS85.1% (81.2-88.2%)80.2% (76.0-83.8%)1.311 (0.961-1.787) Open table in a new tab Long-term follow-up data did not support superiority of No Touch compared with Conventional in the patents with stage II and III colon cancer.

Long-term follow-upexperience with adjuvant therapy after irreversible electroporation of locally advanced pancreatic cancer.

Irreversible electroporation (IRE) expands the surgical options for patients with unresectable pancreatic cancer. This study evaluated for differences in survival stratified by type of IRE and receipt of adjuvant chemotherapy. Patients with locally advanced pancreatic cancer treated by IRE (2012-2020) were retrospectively included. Overall survival (OS) and recurrence-free survival (RFS) were compared by type of IRE (in situ for local tumor control or IRE of potentially positive margins with resection) and by receipt of adjuvant chemotherapy. Thirty-nine patients had IRE in situ, 61 had IRE for margin extension, and 19 received adjuvant chemotherapy. Most (97.00%) underwent induction chemotherapy. OS was 28.71 months (interquartile range [IQR] 19.17, 51.19) from diagnosis, with no difference by IRE type (hazard ratio [HR] 1.05 for margin extension [p = 0.85]) or adjuvant chemotherapy (HR 1.14 [p = 0.639]). RFS was 8.51 months (IQR 4.95, 20.17) with no difference by IRE type (HR 0.90 for margin extension [p = 0.694]) or adjuvant chemotherapy (HR 0.90 [p = 0.711]). These findings suggest that adjuvant therapy may have limited benefit for patients treated with induction chemotherapy followed by local control with IRE for unresectable pancreatic cancer. Further study of the duration and timing of systemic therapy is warranted to maximize benefit and limit toxicity.

Adherence to EndoPredict test scores for extended endocrine therapy management in the prospective EndoPredict Extended Endocrine Trial (EXET).

537 Background: Current guidelines advise that individuals with estrogen receptor-positive (ER+) breast cancer (BC) undergo 5 years of endocrine therapy with consideration of up to 10 years of extended endocrine therapy (EET). The relative benefit of EET beyond 5 years is minimal for many patients, yet a significant group of patients at higher risk of late recurrence may benefit. EndoPredict is a gene expression assay to stratify those with high versus low BC recurrence risk and is validated to predict early and late distant metastasis up to 15 years using an EPclin score. In the prospective EXET study we evaluated adherence to EndoPredict test results when making decisions regarding EET. Methods: Patients with prior ER+, human epidermal growth factor 2 negative (HER2-) BC diagnosis and 4-6.5 years of endocrine therapy underwent EndoPredict testing. To evaluate the impact on decision making for EET, chart review was performed at or after test results were clinically disclosed. Univariable analysis was used for EPclin risk classification (high, low), multivariable analysis was used to evaluate the EPclin score with clinical variables and Firth logistic regression was used to assess the association of a given variable with the therapy decision. Results: The cohort consisted of 411 patients with an average age of 62 years (range 27, 90), 107 received adjuvant chemotherapy (26%), and 71 were lymph node positive (17.3%). The rate of EET was significantly different for those with low-risk scores (EPclin Score ≤ 3.3) compared to high-risk scores (EPclin Score > 3.3; OR 8.5×10-4 [95% CI 6.8×10-6, 6.0×10-3], p-value 5.7×10-68). All patients with high-risk scores received EET. Within the low-risk group, those treated with adjuvant chemotherapy and those who were lymph node positive chose to extend endocrine therapy at higher rates. The EPclin score provided significant information in predicting EET status, even when accounting for clinical variables such as node status, tumor grade, age at diagnosis, adjuvant chemotherapy status and tumor stage (EPclin Score OR 20.2 [10.1, 44.0]; p-value=3.1 × 10-25). Conclusions: Even after adjusting for other clinical factors, EndoPredict is a significant predictor of clinical decision on EET. High adherence to EndoPredict test results in EET decision making was noted in our study. Clinical trial information: NCT04016935. [Table: see text]