Comparison of incident breast cancer cases in the largest national US tumor registries.

BACKGROUND: This study compared incident breast cancer cases in the National Cancer Database (NCDB) and Surveillance, Epidemiology, End Results Program (SEER) to a national population cancer registry. METHODS: Patients with malignant or in situ breast cancer (BC) 2010-2019 in the NCDB and SEER were compared to the US Cancer Statistics (USCS). Case coverage was estimated as the number of patients in the NCDB/SEER as a proportion of USCS cases. RESULTS: The USCS reported 3,047,509 patients; 77.5% patients were included in the NCDB and 46.0% in SEER. Case ascertainment varied significantly by patient sex (both registries, p < .001). For males, 84.1% were captured in the NCDB, whereas only 77.5% of females were included. Case coverage in SEER was better for females than males (46.1% vs. 43.5%). Registries varied significantly by race/ethnicity (both p < .001). Case coverage in the NCDB was highest for non-Hispanic White (78.2%), non-Hispanic Black (77.7%), and non-Hispanic Asian or Pacific Islander (72.5%) BC patients, and lowest for Hispanic (56.4%) and non-Hispanic American Indian/Alaska Native (41.1%) patients. In SEER, case coverage was highest for non-Hispanic Asian or Pacific Islander (78.1%) and Hispanic (69.6%) patients and it was significantly lower for all other subgroups (non-Hispanic Black, 44.8%; non-Hispanic White, 42.4%; and non-Hispanic American Indian/Alaska Native, 36.6%). CONCLUSIONS: National US tumor registries provide data for a large sampling of breast cancer patients, yet significant differences in case coverage were observed based on age, sex, and race/ethnicity. These findings suggest that analyses using these data sets and interpretation of findings should account for these meaningful variances.

Examining inequities associated with incarceration among breast cancer patients.

INTRODUCTION: Breast cancer treatment patterns and quality of care among patients experiencing incarceration are underexplored. This study examined associations between incarceration and breast cancer disease and treatment characteristics. METHODS: This retrospective analysis was conducted at a tertiary center in the Southeastern United States that serves as the state's safety-net hospital and primary referral site for the state's prisons. All patients ≥18 years diagnosed with breast cancer between 4/14/2014-12/30/2020 were included. Incarceration status was determined through electronic health record review. Linear regression was used to estimate the association of incarceration with time to treatment. Unadjusted overall survival (OS) was estimated using the Kaplan-Meier method with log-rank tests to compare groups. RESULTS: Of the 4329 patients included, 30 (0.7%) were incarcerated at the time of diagnosis or treatment (DI) and 4299 (99.3%) had no incarceration history (NI). Compared to patients who were NI, patients who were DI were younger (p < 0.001), more likely to be unmarried (p < 0.001), and more likely to have family history of breast cancer (p = 0.02). Patients who were DI had an increased time from diagnosis to neoadjuvant chemotherapy (+47.2 days on average, 95% CI 3.9-90.5, p = 0.03) and from diagnosis to surgery (+20 days on average, 95% CI 6.5-33.5, p = 0.02) compared to NI patients. No difference in OS was observed (log-rank p = 0.70). CONCLUSIONS: Patients who are incarcerated experienced significant delays in breast cancer care. While no differences in mortality were appreciated, these findings are concerning, as they indicate poorer care coordination for patients who are incarcerated. Further research is necessary to understand the full scope of these disparities and elucidate factors that contribute to them.

Rates of Pathologic Complete Response and Overall Survival in Patients with Inflammatory Breast Cancer: A National Cancer Database Study.

BACKGROUND: Patients with inflammatory breast cancer (IBC) have worse survival compared with stage III non-IBC matched cohorts; however, the prognostic significance of achieving pathologic complete response (pCR) in the setting of IBC is not well described. We evaluated overall survival (OS) between IBC patients and non-IBC patients who achieved pCR. METHODS: Adult females diagnosed in 2010-2018 with clinical prognostic stage III unilateral invasive breast cancer treated with neoadjuvant chemotherapy (NAC) followed by surgery were selected from the National Cancer Database. Unadjusted OS from surgery was estimated using the Kaplan-Meier method, and log-rank tests were used to compare groups. Cox proportional hazard models were used to estimate the association of study groups with OS after adjustment for available covariates. RESULTS: The study included 38,390 patients; n = 4600 (12.0%) IBC and n = 33,790 (88.0%) non-IBC. Overall pCR rates were lower for IBC compared with non-IBC (20.7% vs. 23.3%; p < 0.001). Among those achieving pCR, 5-year mortality was higher for IBC patients (16.4%, 95% confidence interval [CI] 13.9-19.1%) versus non-IBC patients (9.1%, 95% CI 8.4-9.8%; log-rank p < 0.001). Among all patients achieving pCR, IBC remained associated with worse OS compared with non-IBC (hazard ratio 1.48, 95% CI 1.19-1.85; p < 0.001). CONCLUSION: We found a lower pCR rate and worse OS in IBC patients compared with non-IBC stage III patients. Despite effective systemic therapies, achieving a pCR for IBC patients may not carry the same prognostic impact compared with non-IBC stage III patients.

Assessment of Treatment Sequence in Patients With Stage III Breast Cancer.

INTRODUCTION: Stage III breast cancer is defined as locally advanced breast cancer and is treated with curative intent. Historically, overall survival (OS) did not differ based on treatment sequence (neoadjuvant chemotherapy [NAC] followed by surgery versus surgery followed by chemotherapy). Given recent advancements, we examined if treatment sequence may be associated with improved OS in a contemporary cohort of patients with stage III breast cancer. METHODS: Patients aged 18-80 years with prognostic stage III breast cancer who received chemotherapy and surgery were selected from the Surveillance, Epidemiology, and End Results database. Patients were stratified by treatment sequence (NAC versus surgery first). Unadjusted OS and breast cancer-specific survival (BCSS) were estimated using the Kaplan-Meier method and compared with log-rank tests. Cox proportional hazards models were used to estimate the association of treatment sequence with OS and BCSS after adjustment for selected covariates. RESULTS: The study included 26,573 patients; median follow-up was 62.0 months (95% confidence interval [CI] 61.0-63.0). Patients receiving NAC had a worse OS and BCSS compared to those who underwent surgery first (5-year OS rates 0.66 versus 0.73; 5-year BCSS rates 0.70 versus 0.77; both log-rank P < 0.001). After adjustment for tumor subtype, receipt of NAC (versus surgery first) remained associated with a worse OS (hazard ratio 1.27, 95% CI 1.2-1.34, P < 0.001) and BCSS (hazard ratio 1.35, 95% CI 1.27-1.43, P < 0.001). CONCLUSIONS: Based on data from patients treated largely before 2020, undergoing surgery first may be associated with improved survival, even after adjustment for known covariates including tumor subtype. These findings may inform treatment when caring for patients with operable, locally advanced breast cancer.

Trajectory of Subsequent Breast Cancer Diagnoses in a Diverse Patient Cohort with Breast Atypia.

BACKGROUND: Proliferative breast atypical lesions, including atypical ductal hyperplasia (ADH) and lobular intraepithelial neoplasms (LIN), represent benign entities that confer an elevated risk of ductal carcinoma in situ (DCIS) and invasive breast cancer (IBC). However, the timing of disease progression is variable and risk factors associated with the trajectory of disease are unknown. METHODS: Patients diagnosed with ADH or LIN from 1992 to 2017 at an academic center were identified. Early progression was defined as DCIS or IBC diagnosed within 5 years following the initial atypia diagnosis. Unadjusted cancer-free survival was estimated using the Kaplan-Meier method. Demographics, clinicopathologic features, and use of chemoprevention were compared between the early and late development groups. RESULTS: Overall, 418 patients were included-73.7% with ADH and 26.3% with LIN. Over a median follow up of 92.1 months, 71/418 (17.0%) patients developed IBC (57.7%) or DCIS (42.3%). Almost half (47.9%, 34/71) were diagnosed within 5 years of their initial atypia diagnosis, and 52.1% (37/71) were diagnosed after 5 years. Patient and atypia characteristics were not associated with rate of events or time to events. There was a trend of early events being more often ipsilateral (76.5% early vs. 54.1% late; p = 0.13) versus contralateral. CONCLUSIONS: In a large cohort of patients with breast atypia and long-term follow up, 17% experienced subsequent breast events, with approximately half of the events occurring within the first 5 years following the initial atypia diagnosis. Clinical features were not associated with the trajectory to subsequent events, supporting that atypia signals both local and overall malignancy risk.

Utility of Axillary Staging in Older Patients with HER2-Positive Breast Cancer.

BACKGROUND: The utility of sentinel lymph node biopsy (SLNB) in older patients remains controversial. Advancements in human epidermal growth factor receptor 2 (HER2)-directed therapy have revolutionized disease response rates and prognosis, supporting efforts to re-evaluate the utility of SLNB. We aimed to assess the differences in treatment and overall survival (OS) in older patients with HER2-positive breast cancer based on SLNB. METHODS: Using the National Cancer Database (2010-2020), patients ≥ 70 years of age diagnosed with cT1-2/cN0/M0, HER2-positive breast cancer were identified. Logistic regression assessed associations with SLNB, systemic therapy, and radiation. Cox proportional hazard models were used to identify factors associated with OS. Analyses were stratified by treatment sequence, i.e. upfront surgery or neoadjuvant therapy (NAT) followed by surgery. RESULTS: Of the 17,609 patients included, 94% underwent upfront surgery (n = 16,492) and the remaining underwent NAT (n = 1117). Those who underwent SLNB were more likely to receive adjuvant therapy, irrespective of nodal status {upfront surgery/systemic therapy (odds ratio [OR] 2.82, 95% confidence interval [CI] 2.17-3.67); upfront surgery/radiation (OR 3.97, 95% CI 3.03-5.21); NAT/radiation (OR 5.69, 95% CI 1.83-17.69)}. The breast pathologic complete response (pCR) rate was highest among the hormone receptor (HR)-negative/HER2-positive subtype (50.0%), of which none were found to be ypN+. Comorbidity burden was associated with significantly lower rates of adjuvant systemic therapy and worse OS. CONCLUSIONS: Patients who underwent SLNB, regardless of pN status, were more likely to receive adjuvant therapy. Nodal positivity is exceedingly rare for patients with a breast pCR following NAT, especially among the HR-negative/HER2-positive subtype. It is reasonable to consider omission of SLNB in select subgroups of older patients with HER2-positive breast cancer.

Demographics and Clinical Decision Making in Patients with Germline Moderate Penetrance Non-BRCA Mutations in Breast Cancer Related Genes.

BACKGROUND: Management of pathogenic variants in high penetrance genes related to breast cancer (BC), such as BRCA1 and BRCA2, are well established. However, moderate penetrance mutations are understudied. We aim to compare risk reduction decision-making patterns in patients with a moderate penetrance BC-related genetic mutations, without a prior BC diagnosis. PATIENTS AND METHODS: Female patients aged ≥ 18 years who tested positive for a BRCA1/2, high penetrance, or moderate penetrance mutation related to BC between 1996 and 2023 without a concurrent or prior BC diagnosis were retrospectively identified from a single academic center's database. Groups were stratified by mutation type: BRCA1/2 mutations (BRCA1, BRCA2), high penetrance mutations (HPM; CDH1, PALB2, PTEN, STK11, TP53), or moderate penetrance mutations (MPM; ATM, BARD1, CHEK2, NF1, RAD51C, RAD51D). Demographics and clinical outcomes were compared. RESULTS: A total of 528 patients met the inclusion criteria, with 66% (n = 350) having a BRCA1/2 mutation, 8% (n = 44) having HPM, and 25% (n = 134) having MPM; the median follow-up was 56.0 months. In our cohort, 20.9% of patients with BRCA mutations, 9.1% with HPM, and 7.5% with MPM chose to undergo risk-reducing mastectomies (RRM). Within the moderate penetrance cohort, patients who chose to undergo RRM were younger at the time of genetic testing (39.4 vs. 47.5 years, p = 0.03) and had a higher number of family members with BC (2 vs. 1, p = 0.05). CONCLUSIONS: Our findings provide insights into the demographic characteristics and family history of patients with moderate penetrance mutations and those who pursue risk-reducing surgery.

Guideline-Concordant Surgical Care for Lobular Versus Ductal Inflammatory Breast Cancer.

INTRODUCTION: Quality of surgical care is understudied for lobular inflammatory breast cancer (IBC), which is less common, more chemotherapy-resistant, and more mammographically occult than ductal IBC. We compared guideline-concordant surgery (modified radical mastectomy [MRM] without immediate reconstruction following chemotherapy) for lobular versus ductal IBC. METHODS:  Female individuals with cT4dM0 lobular and ductal IBC were identified in the National Cancer Database (NCDB) from 2010-2019. Modified radical mastectomy receipt was identified via codes for "modified radical mastectomy" or "mastectomy" and "≥10 lymph nodes removed" (proxy for axillary lymph node dissection). Descriptive statistics, chi-square tests, and t-tests were used. RESULTS: A total of 1456 lobular and 10,445 ductal IBC patients were identified; 599 (41.1%) with lobular and 4859 (46.5%) with ductal IBC underwent MRMs (p = 0.001). Patients with lobular IBC included a higher proportion of individuals with cN0 disease (20.5% lobular vs. 13.7% ductal) and no lymph nodes examined at surgery (31.2% vs. 24.5%) but were less likely to be node-negative at surgery (12.7% vs. 17.1%, all p < 0.001). Among those who had lymph nodes removed at surgery, patients with lobular IBC also had fewer lymph nodes excised versus patients with ductal IBC (median [interquartile range], 7 (0-15) vs. 9 (0-17), p = 0.001). CONCLUSIONS: Lobular IBC patients were more likely to present with node-negative disease and less likely to be node-negative at surgery, despite having fewer, and more frequently no, lymph nodes examined versus ductal IBC patients. Future studies should investigate whether these treatment disparities are because of surgical approach, pathologic assessment, and/or data quality as captured in the NCDB.

Improving symptom management for survivors of young adult cancer: rationale and study protocol for a pilot randomized controlled trial.

BACKGROUND: Young adult (YA) cancer survivors are a growing, yet underserved population who often face significant and long-lasting cancer-related physical (e.g., pain, fatigue) and emotional (e.g., psychological distress) symptoms. Post-treatment symptoms can persist, disrupting YA's abilities to complete goals consistent with their developmental stage (e.g., completing their education, achieving autonomy and independence, building their careers, establishing peer and romantic relationships, building their families). While symptom management has been identified as a significant issue in YA's transitions to survivorship, the symptom management needs of this population largely go unmet. METHODS: We developed an eight-session, group-based behavioral intervention that is delivered using videoconferencing to address the unique symptom management needs of YA cancer survivors. The intervention was developed in conjunction with YA survivors, leading to the novel combination of traditional behavioral symptom coping strategies, home-based physical activity, strategies from contemporary cognitive-behavioral approaches (e.g., those derived from acceptance and commitment therapy, strategies to foster self-compassion), concepts from meaning centered psychotherapy, and behavioral strategies to improve communication and health care engagement. Participants receive printed intervention materials and access to a study-specific mobile application, both of which are used throughout the program. Herein, we report on a pilot study that is in progress. Recruitment has been completed. YA cancer survivors were recruited in cohorts of n = 10 or n = 11 (n = 61) and randomized to the intervention or waitlist control arms. All participants completed a baseline assessment and four additional assessments over 1 year, with each involving a battery of self-report measures. DISCUSSION: The primary objective is to evaluate intervention feasibility and acceptability. As a secondary objective, we will examine patterns of change in intervention targets (i.e., pain, fatigue, emotional distress, symptom interference). Changes from baseline among intervention targets will be estimated for each patient and compared between arms using unadjusted statistical testing. Unadjusted and adjusted multilevel modeling will be used to estimate the effect of the intervention on changes in intervention targets. Interaction models will be used to compare the trajectory of change over time between arms. We expect that this pilot trial will inform our future approach to identify, recruit, and retain participants and provide preliminary data to support a larger, fully powered randomized controlled trial evaluating the intervention. TRIAL REGISTRATION: NCT04035447 at clinicaltrials.gov; registered July 29, 2019.

Patient Characteristics Impact Performance of AI Algorithm in Interpreting Negative Screening Digital Breast Tomosynthesis Studies.

Background Artificial intelligence (AI) is increasingly used to manage radiologists' workloads. The impact of patient characteristics on AI performance has not been well studied. Purpose To understand the impact of patient characteristics (race and ethnicity, age, and breast density) on the performance of an AI algorithm interpreting negative screening digital breast tomosynthesis (DBT) examinations. Materials and Methods This retrospective cohort study identified negative screening DBT examinations from an academic institution from January 1, 2016, to December 31, 2019. All examinations had 2 years of follow-up without a diagnosis of atypia or breast malignancy and were therefore considered true negatives. A subset of unique patients was randomly selected to provide a broad distribution of race and ethnicity. DBT studies in this final cohort were interpreted by a U.S. Food and Drug Administration-approved AI algorithm, which generated case scores (malignancy certainty) and risk scores (1-year subsequent malignancy risk) for each mammogram. Positive examinations were classified based on vendor-provided thresholds for both scores. Multivariable logistic regression was used to understand relationships between the scores and patient characteristics. Results A total of 4855 patients (median age, 54 years [IQR, 46-63 years]) were included: 27% (1316 of 4855) White, 26% (1261 of 4855) Black, 28% (1351 of 4855) Asian, and 19% (927 of 4855) Hispanic patients. False-positive case scores were significantly more likely in Black patients (odds ratio [OR] = 1.5 [95% CI: 1.2, 1.8]) and less likely in Asian patients (OR = 0.7 [95% CI: 0.5, 0.9]) compared with White patients, and more likely in older patients (71-80 years; OR = 1.9 [95% CI: 1.5, 2.5]) and less likely in younger patients (41-50 years; OR = 0.6 [95% CI: 0.5, 0.7]) compared with patients aged 51-60 years. False-positive risk scores were more likely in Black patients (OR = 1.5 [95% CI: 1.0, 2.0]), patients aged 61-70 years (OR = 3.5 [95% CI: 2.4, 5.1]), and patients with extremely dense breasts (OR = 2.8 [95% CI: 1.3, 5.8]) compared with White patients, patients aged 51-60 years, and patients with fatty density breasts, respectively. Conclusion Patient characteristics influenced the case and risk scores of a Food and Drug Administration-approved AI algorithm analyzing negative screening DBT examinations. © RSNA, 2024.

Health Care Cost Reductions with Machine Learning-Directed Evaluations during Radiation Therapy - An Economic Analysis of a Randomized Controlled Study.

BACKGROUND: Machine learning (ML) may cost-effectively direct health care by identifying patients most likely to benefit from preventative interventions to avoid negative and expensive outcomes. System for High-Intensity Evaluation During Radiation Therapy (SHIELD-RT; NCT04277650) was a single-institution, randomized controlled study in which electronic health record-based ML accurately identified patients at high risk for acute care (emergency visit or hospitalization) during radiotherapy (RT) and targeted them for supplemental clinical evaluations. This ML-directed intervention resulted in decreased acute care utilization. Given the limited prospective data showing the ability of ML to direct interventions cost-efficiently, an economic analysis was performed. METHODS: A post hoc economic analysis was conducted of SHIELD-RT that included RT courses from January 7, 2019, to June 30, 2019. ML-identified high-risk courses (≥10% risk of acute care during RT) were randomized to receive standard of care weekly clinical evaluations with ad hoc supplemental evaluations per clinician discretion versus mandatory twice-weekly evaluations. The primary outcome was difference in mean total medical costs during and 15 days after RT. Acute care costs were obtained via institutional cost accounting. Physician and intervention costs were estimated via Medicare and Medicaid data. Negative binomial regression was used to estimate cost outcomes after adjustment for patient and disease factors. RESULTS: A total of 311 high-risk RT courses among 305 patients were randomized to the standard (n=157) or the intervention (n=154) group. Unadjusted mean intervention group supplemental visit costs were $155 per course (95% confidence interval, $142 to $168). The intervention group had fewer acute care visits per course (standard, 0.47; intervention, 0.31; P=0.04). Total mean adjusted costs were $3110 per course for the standard group and $1494 for the intervention group (difference in means, $1616 [95% confidence interval, $1450 to $1783]; P=0.03). CONCLUSIONS: In this economic analysis of a randomized controlled, health care ML study, mandatory supplemental evaluations for ML-identified high-risk patients were associated with both reduced total medical costs and improved clinical outcomes. Further study is needed to determine whether economic results are generalizable. (Funded in part by The Duke Endowment, The Conquer Cancer Foundation, the Duke Department of Radiation Oncology, and the National Cancer Institute of the National Institutes of Health [R01CA277782]; ClinicalTrials.gov number, NCT04277650.).

Critical updates in neuroendocrine tumors: Version 9 American Joint Committee on Cancer staging system for gastroenteropancreatic neuroendocrine tumors.

The American Joint Committee on Cancer (AJCC) staging system for all cancer sites, including gastroenteropancreatic neuroendocrine tumors (GEP-NETs), is meant to be dynamic, requiring periodic updates to optimize AJCC staging definitions. This entails the collaboration of experts charged with evaluating new evidence that supports changes to each staging system. GEP-NETs are the second most prevalent neoplasm of gastrointestinal origin after colorectal cancer. Since publication of the AJCC eighth edition, the World Health Organization has updated the classification and separates grade 3 GEP-NETs from poorly differentiated neuroendocrine carcinoma. In addition, because of major advancements in diagnostic and therapeutic technologies for GEP-NETs, AJCC version 9 advocates against the use of serum chromogranin A for the diagnosis and monitoring of GEP-NETs. Furthermore, AJCC version 9 recognizes the increasing role of endoscopy and endoscopic resection in the diagnosis and management of NETs, particularly in the stomach, duodenum, and colorectum. Finally, T1NXM0 has been added to stage I in these disease sites as well as in the appendix.

Dietary Nitrate Metabolism in Porcine Ocular Tissues Determined Using 15N-Labeled Sodium Nitrate Supplementation.

Nitrate (NO3-) obtained from the diet is converted to nitrite (NO2-) and subsequently to nitric oxide (NO) within the body. Previously, we showed that porcine eye components contain substantial amounts of nitrate and nitrite that are similar to those in blood. Notably, cornea and sclera exhibited the capability to reduce nitrate to nitrite. To gain deeper insights into nitrate metabolism in porcine eyes, our current study involved feeding pigs either NaCl or Na15NO3 and assessing the levels of total and 15N-labeled NO3-/NO2- in various ocular tissues. Three hours after Na15NO3 ingestion, a marked increase in 15NO3- and 15NO2- was observed in all parts of the eye; in particular, the aqueous and vitreous humor showed a high 15NO3- enrichment (77.5 and 74.5%, respectively), similar to that of plasma (77.1%) and showed an even higher 15NO2- enrichment (39.9 and 35.3%, respectively) than that of plasma (19.8%). The total amounts of NO3- and NO2- exhibited patterns consistent with those observed in 15N analysis. Next, to investigate whether nitrate or nitrite accumulate proportionally after multiple nitrate treatments, we measured nitrate and nitrite contents after supplementing pigs with Na15NO3 for five consecutive days. In both 15N-labeled and total nitrate and nitrite analysis, we did not observe further accumulation of these ions after multiple treatments, compared to a single treatment. These findings suggest that dietary nitrate supplementation exerts a significant influence on nitrate and nitrite levels and potentially NO levels in the eye and opens up the possibility for the therapeutic use of dietary nitrate/nitrite to enhance or restore NO levels in ocular tissues.

Survival among patients with untreated metastatic breast cancer: "What if I do nothing?"

PURPOSE: We sought to assess survival outcomes of patients with de novo metastatic breast cancer (dnMBC) who did not receive treatment irrespective of the reason. METHODS: Adults with dnMBC were selected from the NCDB (2010-2016) and stratified based on receipt of treatment (treated = received at least one treatment and untreated = received no treatments). Overall survival (OS) was estimated using the Kaplan-Meier method, and groups were compared. Cox proportional hazards models were used to identify factors associated with OS. RESULTS: Of the 53,240 patients with dnMBC, 92.1% received at least one treatment (treated), and 7.9% had no documented treatments, irrespective of the reason (untreated). Untreated patients were more likely to be older (median 68 y vs 61 y, p < 0.001), have higher comorbidity scores (p < 0.001), have triple-negative disease (17.8% vs 12.6%), and a higher disease burden (≥ 2 metastatic sites: 38.2% untreated vs 29.2% treated, p < 0.001). The median unadjusted OS in the untreated subgroup was 2.5 mo versus 36.4 mo in the treated subgroup (p < 0.001). After adjustment, variables associated with a worse OS in the untreated cohort included older age, higher comorbidity scores, higher tumor grade, and triple-negative (vs HR + /HER2-) subtype (all p < 0.05), while the number of metastatic sites was not associated with survival. CONCLUSIONS: Patients with dnMBC who do not receive treatment are more likely to be older, present with comorbid conditions, and have clinically aggressive disease. Similar to those who do receive treatment, survival in an untreated population is associated with select patient and disease characteristics. However, the prognosis for untreated dnMBC is dismal.

Anatomy Versus Biology: What Guides Chemotherapy Decisions in Older Patients With Breast Cancer?

INTRODUCTION: With the increasing utilization of genomic assays, such as the Oncotype DX recurrence score (RS), the relevance of anatomic staging has been questioned for select older patients with breast cancer. We sought to evaluate differences in chemotherapy receipt and/or survival among older patients based on RS and sentinel lymph node biopsy (SLNB) receipt/result. METHODS: Patients aged ≥ 65 diagnosed with pT1-2/cN0/M0 hormone-receptor-positive (HR+)/HER2-breast cancer (2010-2019) were selected from the National Cancer Database. Logistic regression was used to identify factors associated with chemotherapy receipt. Cox proportional hazards models were used to estimate the association of RS/SLNB group with overall survival. A cost-benefit study was also performed. RESULTS: Of the 75,428 patients included, the majority had an intermediate RS (58.2% versus 27.9% low, 13.8% high) and were SLNB- (85.1% versus 11.6% SLNB+, 3.3% none). Chemotherapy was recommended for 13,442 patients (17.8%). After adjustment, chemotherapy receipt was more likely with higher RS and SLNB+. After adjustment, SLNB receipt/result was only associated with overall survival among those with an intermediate RS. However, returning to the OR for SLNB is not cost-effective. CONCLUSIONS: SLNB receipt/result was associated with survival for those with an intermediate RS, but not a low or high RS, suggesting that an SLNB may indeed be unnecessary for select older patients with breast cancer.

Axillary nodal disease burden is not associated with an elevated 21-gene recurrence score in post-menopausal women presenting with a clinically negative axilla.

BACKGROUND: The predictive and prognostic value of the recurrence score (RS) has emphasized the importance of tumor biology and has reduced the prognostic implications of limited nodal burden in post-menopausal women with HR+/HER2-invasive breast cancer (IBC). It is unclear whether routine axillary staging has a continued role in the management of small, clinically node negative (cN0) HR+/HER2- IBC. We sought to estimate the association of RS with pN stage. METHODS: Patients >50yo diagnosed with cN0, HR+/HER2- IBC (2015-2019) with an available RS were identified from the National Cancer Database. The clinicopathologic characteristics and rates of pN-stage (pN0, pN1, pN2/3) were compared for RS of ≤25 vs. >25. RESULTS: The median patient age was 64.1 (IQR 58-69) and the majority (75%) of tumors displayed ductal histology. Most (81.6%) were cT1 on presentation and pT1 (74.7%) on final pathology. There were 130,568 (86.2%) with a RS â€‹≤ â€‹25 and 20,879 (13.8%) with a RS â€‹> â€‹25. On final pathology, 128,995 (85.2%) were pN0 and 21,991 (14.5%) pN1. Of the pN1, 2699 (12.3%) yielded a RS â€‹> â€‹25. There were 461 (0.3%) patients with pN2-pN3 disease. Of those, 57 (12.4%) had RS â€‹> â€‹25. CONCLUSION: In our analysis, pN0 and pN1 tumors are biologically similar by gene expression assay in postmenopausal patients with similar proportions of high RS. These data support the notion that tumor biology examined via RS may have more prognostic and predictive value than metastatic dissemination to limited lymph nodes. These findings support the ongoing evaluation of routine axillary staging in postmenopausal patients with HR+/HER2- IBC.