Germline Testing in Patients With Breast Cancer: ASCO-Society of Surgical Oncology Guideline

PURPOSE

To develop recommendations for germline mutation testing for patients with breast cancer.

METHODS

An ASCO-Society of Surgical Oncology (SSO) panel convened to develop recommendations based on a systematic review and formal consensus process.

RESULTS

Forty-seven articles met eligibility criteria for the germline mutation testing recommendations; 18 for the genetic counseling recommendations.

RECOMMENDATIONS

BRCA1/2 mutation testing should be offered to all newly diagnosed patients with breast cancer ≤65 years and select patients >65 years based on personal history, family history, ancestry, or eligibility for poly(ADP-ribose) polymerase (PARP) inhibitor therapy. All patients with recurrent breast cancer who are candidates for PARP inhibitor therapy should be offered BRCA1/2 testing, regardless of family history. BRCA1/2 testing should be offered to women who develop a second primary cancer in the ipsilateral or contralateral breast. For patients with prior history of breast cancer and without active disease, testing should be offered to patients diagnosed ≤65 years and selectively in patients diagnosed after 65 years, if it will inform personal and family risk. Testing for high-penetrance cancer susceptibility genes beyond BRCA1/2 should be offered to those with supportive family histories; testing for moderate-penetrance genes may be offered if necessary to inform personal and family cancer risk. Patients should be provided enough pretest information for informed consent; those with pathogenic variants should receive individualized post-test counseling. Variants of uncertain significance should not impact management, and patients with such variants should be followed for reclassification. Referral to providers experienced in clinical cancer genetics may help facilitate patient selection and interpretation of expanded testing, and provide counseling of individuals without pathogenic germline variants but with significant family history.Additional information is available at www.asco.org/breast-cancer-guidelines.

Implementation of a novel peer review academy by Surgery and the Association of Women Surgeons

BACKGROUND

A novel Peer Review Academy was developed as a collaborative effort between the Association of Women Surgeons and the journal Surgery to provide formal training in peer review. We aimed to describe the outcomes of this initiative using a mixed methods approach.

METHODS

We developed a year-long curriculum with monthly online didactic sessions. Women surgical trainee mentees were paired 1:1 with rotating women surgical faculty mentors for 3 formal peer review opportunities. We analyzed pre-course and post-course surveys to evaluate mentee perceptions of the academy and assessed changes in mentee review quality over time with blinded scoring of unedited reviews. Semi-structured interviews were conducted upon course completion.

RESULTS

Ten women surgical faculty mentors and 10 women surgical trainees from across the United States and Canada successfully completed the Peer Review Academy. There were improvements in the mentees' confidence for all domains of peer review evaluated, including overall confidence in peer review, study novelty, study design, analytic approach, and review formatting (all, P ≤ .02). The mean score of peer review quality increased over time (59.2 ± 10.8 vs 76.5 ± 9.4; P = .02). In semi-structured interviews, important elements were emphasized across the Innovation, Implementation Process, and Individuals Domains, including the values of (1) a comprehensive approach to formal peer review education; (2) mentoring relationships between women faculty and resident surgeons; and (3) increasing diversity in the scientific peer review process.

CONCLUSION

Our novel Peer Review Academy was feasible on a national scale, resulting in significant qualitative and quantitative improvements in women surgical trainee skillsets, and has the potential to grow and diversify the existing peer review pool.

Impact of HER2-low status for patients with early-stage breast cancer and non-pCR after neoadjuvant chemotherapy: a National Cancer Database Analysis

PURPOSE

To investigate potential differences in pathological complete response (pCR) rates and overall survival (OS) between HER2-low and HER2-zero patients with early-stage hormone receptor (HR)-positive and triple-negative breast cancer (TNBC), in the neoadjuvant chemotherapy setting.

METHODS

We identified early-stage invasive HER2-negative BC patients who received neoadjuvant chemotherapy diagnosed between 2010 and 2018 in the National Cancer Database. HER2-low was defined by immunohistochemistry (IHC) 1+ or 2+ with negative in situ hybridization, and HER2-zero by IHC0. All the methods were applied separately in the HR-positive and TNBC cohorts. Logistic regression was used to estimate the association of HER2 status with pCR (i.e. ypT0/Tis and ypN0). Kaplan-Meier method and Cox proportional hazards model were applied to estimate the association of HER2 status with OS. Inverse probability weighting and/or multivariable regression were applied to all analyses.

RESULTS

For HR-positive patients, 70.9% (n = 17,934) were HER2-low, whereas 51.1% (n = 10,238) of TNBC patients were HER2-low. For both HR-positive and TNBC cohorts, HER2-low status was significantly associated with lower pCR rates [HR-positive: 5.0% vs. 6.7%; weighted odds ratio (OR) = 0.81 (95% CI: 0.72-0.91), p < 0.001; TNBC: 21.6% vs. 24.4%; weighted OR = 0.91 (95% CI: 0.85-0.98), p = 0.007] and improved OS [HR-positive: weighted hazard ratio = 0.85 (95% CI: 0.79-0.91), p < 0.001; TNBC: weighted hazard ratio = 0.91 (95% CI: 0.86-0.96), p < 0.001]. HER2-low status was associated with favorable OS among patients not achieving pCR [HR-positive: adjusted hazard ratio = 0.83 (95% CI: 0.77-0.89), p < 0.001; TNBC: adjusted hazard ratio = 0.88 (95% CI 0.83-0.94), p < 0.001], while no significant difference in OS was observed in patients who achieved pCR [HR-positive: adjusted hazard ratio = 1.00 (95% CI: 0.61-1.63), p > 0.99; TNBC: adjusted hazard ratio = 1.11 (95% CI: 0.85-1.45), p = 0.44].

CONCLUSION

In both early-stage HR-positive and TNBC patients, HER2-low status was associated with lower pCR rates. HER2-zero status might be considered an adverse prognostic factor for OS in patients not achieving pCR.

BRCA1/2 mutation carriers & risk reducing mastectomy: Who undergoes surgery and potential benefits

BACKGROUND

Risk-reducing mastectomy (RRM) is the most effective breast cancer risk-reduction strategy in BRCA1/2 mutation carriers. We examined factors associated with RRM and its relationship with overall survival (OS).

METHODS

Patients aged 18-80y at diagnosis of their BRCA1/2 mutation were selected from our institutional database and stratified by RRM receipt. Differences were tested; unadjusted OS was estimated.

RESULTS

Of the 306 patients, median age was 43y; median follow-up was 41.6mo. Patients undergoing RRM were more often married with a history of pregnancy (both p ​≤ ​0.05). Of female patients, 23.1% underwent RRM. Two patients had malignancy detected at RRM, and one developed breast cancer after RRM. Higher unadjusted OS was observed with RRM (p ​= ​0.02).

CONCLUSIONS

Our analyses suggest that family-structure may play a role in a patient's decision to undergo RRM. We also demonstrated RRM is likely associated with improved survival, potentially underscoring the importance of this option for BRCA1/2 mutation carriers.

Immune Phenotype and Postoperative Complications After Elective Surgery

OBJECTIVES

To characterize and quantify accumulating immunologic alterations, pre and postoperatively in patients undergoing elective surgical procedures.

BACKGROUND

Elective surgery is an anticipatable, controlled human injury. Although the human response to injury is generally stereotyped, individual variability exists. This makes surgical outcomes less predictable, even after standardized procedures, and may provoke complications in patients unable to compensate for their injury. One potential source of variation is found in immune cell maturation, with phenotypic changes dependent on an individual's unique, lifelong response to environmental antigens.

METHODS

We enrolled 248 patients in a prospective trial facilitating comprehensive biospecimen and clinical data collection in patients scheduled to undergo elective surgery. Peripheral blood was collected preoperatively, and immediately on return to the postanesthesia care unit. Postoperative complications that occurred within 30 days after surgery were captured.

RESULTS

As this was an elective surgical cohort, outcomes were generally favorable. With a median follow-up of 6 months, the overall survival at 30 days was 100%. However, 20.5% of the cohort experienced a postoperative complication (infection, readmission, or system dysfunction). We identified substantial heterogeneity of immune senescence and terminal differentiation phenotypes in surgical patients. More importantly, phenotypes indicating increased T-cell maturation and senescence were associated with postoperative complications and were evident preoperatively.

CONCLUSIONS

The baseline immune repertoire may define an immune signature of resilience to surgical injury and help predict risk for surgical complications.

Contralateral Prophylactic Mastectomy Decision-Making: The Partners' Perspective

BACKGROUND

The rate of contralateral prophylactic mastectomy (CPM) continues to rise despite no improvement in survival, an increased risk of surgical complications, and negative effects on quality of life. This study explored the experiences of the partners of women who undergo CPM.

METHODS

This study was part of an investigation into the factors motivating women with early-stage unilateral breast cancer and low genetic risk to opt for contralateral prophylactic mastectomy (CPM). Participating women were asked for permission to invite their partners to take part in interviews. In-depth interviews with partners were conducted using a semi-structured topic guide. A thematic analysis of the data was performed RESULTS: Of 35 partners, all men, 15 agreed to be interviewed. Most perceived their role to be strong and logical. Some hoped their wives would choose a bilateral mastectomy. All felt strongly that the final decision was up to their partners. The partners often framed the decision for CPM as one of life or death. Thus, any aesthetic effects were unimportant by comparison. The male partners had difficulty grasping the physical and emotional changes inherent in mastectomy, which made communicating about sexuality and intimacy very challenging for the couples. In the early recovery period, some noted the stress of managing home life.

CONCLUSIONS

The experiences of the male partners provide insight into how couples navigate complex treatment decision-making, both together and separately. There may be a benefit to including partners in pre- and post-surgical counseling to mitigate miscommunication regarding the expected oncologic and emotional outcomes related to CPM.

Breast Cancer Risk Assessment and Screening Practices Reported Via an Online Survey

BACKGROUND

Breast cancer screening guidelines differ between organizations, and significant variations in practice patterns exist. Previous evidence suggests that provider-level factors are the greatest contributors to risk assessment and screening practice variability. This study aimed to characterize provider factors associated with breast cancer risk assessment and screening practice patterns, and to assess perceived barriers to providing risk assessment.

METHODS

An online survey was distributed to providers at a single academic institution and to providers publicly via social media (January to August 2022). Respondents in the United States who care for adult women at risk for the development of breast cancer were included.

RESULTS

Most of the respondents in the 143 completed surveys were white/Caucasian (79%) females (90%) age 50 years or younger (79%), and whereas 97% discuss breast cancer screening with their patients, only 90% order screening mammograms. Risk factor assessment was common (93%), typically performed at the first visit (51%). Additional training in genetics or risk assessment was uncommon (17%), although the majority were interested but did not have the time or resources (55%). Although most (64%) did not perceive barriers to providing risk assessment or appropriate screening, the most common barriers were time (77%) and education (55%). Barriers were more common among family practice or obstetrics and gynecology (OB/GYN) providers and those who worked in an academic setting (all p < 0.05).

CONCLUSIONS

Breast cancer risk assessment and screening practices are highly variable. Although time is the major barrier to providing risk assessment, providers also need education. Primary care organizations could partner with breast cancer-focused societies for additional resources.

Neoadjuvant Chemotherapy and Endocrine Therapy for Older Patients with Estrogen Receptor Positive Breast Cancer: Comparison of Approaches

BACKGROUND

Benefits of a pathologic complete response (pCR) following neoadjuvant therapy are well established, yet outcomes for older women are understudied. We sought to examine the pCR and overall survival (OS) rates of women with estrogen receptor (ER) positive breast cancer across age groups.

METHODS

Women diagnosed with cT1-4, N0-3, M0, ER+/HER2- breast cancer (2010-2018) who underwent neoadjuvant chemotherapy (NACT) or neoadjuvant endocrine therapy (NET) followed by surgery were selected from the National Cancer Database and categorized by age. Differences were tested, and Cox proportional hazards models were used to estimate the association of response with OS after adjustment for covariates.

RESULTS

In the 43,009-patient cohort, 84.8% received NACT and 15.2% received NET. Of those aged ≥ 70 (N = 5623), 51.0% received NACT, and 49.0% received NET. Compared with younger women receiving NACT, older women were less likely to have a breast or nodal pCR [no pCR by age: 85.1% (≥ 70 years) vs 82.2% (50-69 years) vs 77.7% (< 50 years), p < 0.001]. Rates of pCR were similarly low for all women receiving NET [no pCR by age: 95.6% (≥ 70 years) vs 95% (50-69 years) vs 96% (< 50 years), p = 0.06]. After adjustment, pCR after NACT was not associated with OS for older patients, but better survival outcomes were noted for older patients achieving pCR after NET.

CONCLUSION

For women with ER+/HER2- breast cancer, pCR rates after NACT are lower in older women compared with younger women, and are equally low after NET for all women. However, pCR after NET is associated with improved OS among older women, unlike pCR after NACT.

NCCN Guidelines® Insights: Breast Cancer Screening and Diagnosis, Version 1.2023

The NCCN Guidelines for Breast Cancer Screening and Diagnosis provide health care providers with a practical, consistent framework for screening and evaluating a spectrum of clinical presentations and breast lesions. The NCCN Breast Cancer Screening and Diagnosis Panel is composed of a multidisciplinary team of experts in the field, including representation from medical oncology, gynecologic oncology, surgical oncology, internal medicine, family practice, preventive medicine, pathology, diagnostic and interventional radiology, as well as patient advocacy. The NCCN Breast Cancer Screening and Diagnosis Panel meets at least annually to review emerging data and comments from reviewers within their institutions to guide updates to existing recommendations. These NCCN Guidelines Insights summarize the panel's decision-making and discussion surrounding the most recent updates to the guideline's screening recommendations.

Prognostic Tools for Older Women with Breast Cancer: A Systematic Review

Background: Breast cancer is the most common cancer in women, and older patients comprise an increasing proportion of patients with this disease. The older breast cancer population is heterogenous with unique factors affecting clinical decision making. While many models have been developed and tested for breast cancer patients of all ages, tools specifically developed for older patients with breast cancer have not been recently reviewed. We systematically reviewed prognostic models developed and/or validated for older patients with breast cancer. Methods: We conducted a systematic search in 3 electronic databases. We identified original studies that were published prior to 8 November 2022 and presented the development and/or validation of models based mainly on clinico-pathological factors to predict response to treatment, recurrence, and/or mortality in older patients with breast cancer. The PROBAST was used to assess the ROB and applicability of each included tool. Results: We screened titles and abstracts of 7316 records. This generated 126 studies for a full text review. We identified 17 eligible articles, all of which presented tool development. The models were developed between 1996 and 2022, mostly using national registry data. The prognostic models were mainly developed in the United States (n = 7; 41%). For the derivation cohorts, the median sample size was 213 (interquartile range, 81-845). For the 17 included modes, the median number of predictive factors was 7 (4.5-10). Conclusions: There have been several studies focused on developing prognostic tools specifically for older patients with breast cancer, and the predictions made by these tools vary widely to include response to treatment, recurrence, and mortality. While external validation was rare, we found that it was typically concordant with interval validation results. Studies that were not validated or only internally validated still require external validation. However, most of the models presented in this review represent promising tools for clinical application in the care of older patients with breast cancer.

Novel Prognostic Staging System for Patients With De Novo Metastatic Breast Cancer

PURPOSE

Given the heterogeneity and improvement in outcomes for metastatic breast cancer (MBC), we developed a staging system that refines prognostic estimates for patients with metastatic cancer at the time of initial diagnosis, de novo MBC (dnMBC), on the basis of survival outcomes and disease-related variables.

METHODS

Patients with dnMBC (2010-2016) were selected from the National Cancer Database (NCDB). Recursive partitioning analysis (RPA) was used to group patients with similar overall survival (OS) on the basis of clinical T category, grade, estrogen receptor (ER), progesterone receptor, human epidermal growth factor receptor 2, histology, organ system site of metastases (bone-only, brain-only, visceral), and number of organ systems involved. Three-year OS rates were used to assign a final stage: IVA: >70%, IVB: 50%-70%, IVC: 25 to <50%, and IVD: <25%. Bootstrapping was applied with 1,000 iterations, and final stage assignments were made based on the most commonly occurring assignment. Unadjusted OS was estimated. Validation analyses were conducted using SEER and NCDB.

RESULTS

At a median follow-up of 52.9 months, the median OS of the original cohort (N = 42,467) was 35.4 months (95% CI, 34.8 to 35.9). RPA stratified patients into 53 groups with 3-year OS rates ranging from 73.5% to 5.7%; these groups were amalgamated into four stage groups: 3-year OS, A = 73.2%, B = 61.9%, C = 40.1%, and D = 17% (log-rank P < .001). After bootstrapping, the survival outcomes for the four stages remained significantly different (log-rank P < .001). This staging system was then validated using SEER data (N = 20,469) and a separate cohort from the NCDB (N = 7,645) (both log-rank P < .001).

CONCLUSION

Our findings regarding the heterogeneity in outcomes for patients with dnMBC could guide future revisions of the current American Joint Committee on Cancer staging guidelines for patients with newly diagnosed stage IV disease. Our findings should be independently confirmed.

Survival Benefit of Chemotherapy According to 21-Gene Recurrence Score in Young Women with Breast Cancer

BACKGROUND

Initial trials evaluating Oncotype DX, reported as a recurrence score (RS) from 0 to 100, were not powered to evaluate overall survival, and premenopausal women were underrepresented. The purpose of this study was to explore the benefit of chemotherapy according to RS among younger women eligible for oncotype testing.

METHODS

Women aged 40-50, diagnosed with HR-positive, HER2-negative breast cancer between 2010 and 2017 were selected from the National Cancer Database (NCBD). Patients were grouped by age, RS, nodal status, and chemotherapy receipt. Kaplan-Meier curves were used to compare unadjusted overall survival (OS) between the groups, and log-rank tests were used to test for a difference between groups. Cox proportional hazards models were used to examine the association between select factors and OS.

RESULTS

A total of 15,422 patients met inclusion criteria, 45.3% of whom received chemotherapy. Median follow-up time was 66.4 (50.6-86.6) months. Patients who received chemotherapy were more likely to have higher-stage and higher-grade tumors, tumors that were PR-negative, and have higher RS (p < 0.001 for all). RS was prognostic for OS regardless of nodal status. After adjustment, chemotherapy was associated with a significant improvement in OS only in the pN1 RS 31-50 subgroup (p = 0.02).

CONCLUSIONS

RS retains its prognostic value in younger patients with early stage HR-positive, HER2-negative breast cancer. Chemotherapy survival benefit was limited to patients aged 40-50 with pN1 disease and RS of 31-50. Therefore, chemotherapy decision-making should be especially preference-sensitive in women aged 40-50 with intermediate RS, where it may not provide a survival benefit for many women.

Risk factors for persistent pain after breast cancer surgery: a multicentre prospective cohort study

Identifying factors associated with persistent pain after breast cancer surgery may facilitate risk stratification and individualised management. Single-population studies have limited generalisability as socio-economic and genetic factors contribute to persistent pain development. Therefore, this prospective multicentre cohort study aimed to develop a predictive model from a sample of Asian and American women. We enrolled women undergoing elective breast cancer surgery at KK Women's and Children's Hospital and Duke University Medical Center. Pre-operative patient and clinical characteristics and EQ-5D-3L health status were recorded. Pain catastrophising scale; central sensitisation inventory; coping strategies questionnaire-revised; brief symptom inventory-18; perceived stress scale; mechanical temporal summation; and pressure-pain threshold assessments were performed. Persistent pain was defined as pain score ≥ 3 or pain affecting activities of daily living 4 months after surgery. Univariate associations were generated using generalised estimating equations. Enrolment site was forced into the multivariable model, and risk factors with p < 0.2 in univariate analyses were considered for backwards selection. Of 210 patients, 135 (64.3%) developed persistent pain. The multivariable model attained AUC = 0.807, with five independent associations: age (OR 0.85 95%CI 0.74-0.98 per 5 years); diabetes (OR 4.68, 95%CI 1.03-21.22); pre-operative pain score at sites other than the breast (OR 1.48, 95%CI 1.11-1.96); previous mastitis (OR 4.90, 95%CI 1.31-18.34); and perceived stress scale (OR 1.35, 95%CI 1.01-1.80 per 5 points), after adjusting for: enrolment site; pre-operative pain score at the breast; pre-operative overall pain score at rest; postoperative non-steroidal anti-inflammatory drug use; and pain catastrophising scale. Future research should validate this model and evaluate pre-emptive interventions to reduce persistent pain risk.

Abstract P3-05-20: Low 21-Gene Recurrence Score Is Not Associated with a High Axillary Nodal Burden in Post-Menopausal Women Presenting with a Clinically Negative Axilla

Background: The predictive and prognostic value of the 21-gene recurrence score (RS) has emphasized the importance of tumor biology and minimized the credence of a limited (1-3 positive) nodal burden. The practice changing results of RxPonder demonstrated that post-menopausal women with 1-3 positive lymph nodes (pN1) and a RS of ≤25 did not necessarily benefit from adjuvant chemotherapy. Given that RS influences adjuvant therapy decision-making more significantly than nodal status, it is unclear whether axillary staging with sentinel lymph node biopsy (SLNB) has a continued role in the surgical care of post-menopausal patients otherwise presenting with early stage, clinically node negative (cN0) hormone receptor positive (HR+), human epidermal growth factor receptor 2 negative (HER2-) invasive breast cancer. In this context, the de-escalation of axillary staging, especially in the presence of a low RS, is an area of active investigation. To help elucidate this further, we sought to estimate the association of RS with pathologic nodal stage.

Methods: Using the 2004-2019 National Cancer Database (NCDB) Patient User File (2022 release), we evaluated the association of RS with the incidence of pN0, pN1 and pN2-3 disease. Only female patients diagnosed who were age 50 and older with HR+/HER2- invasive breast cancer were eligible, and only those presenting with cT1-T2N0 who underwent upfront surgery with a SLNB comprised our study population. Those with Oncotype DX testing performed with an available RS were included. Given the limitations within the dataset, age 50 and over was selected as a surrogate for post-menopausal status. Categorical variables were compared between RS groups (≤25 vs. &gt;25) using chi-square tests and continuous variables were compared using t-tests. A logistic regression analysis was performed to estimate the association between RS (≤25 vs. &gt;25) and nodal burden (pN2-3 vs pN0-1).

Results: There were 151,447 patients with an invasive breast cancer diagnosis between 2015 and 2019 who met inclusion criteria. The average age at diagnosis was 64.1 (IQR 58-69) and almost 75% of tumors displayed ductal histology. There were 130,568 (86.2%) patients with a RS≤25 and 20,879 (13.8%) with a RS &gt;25. On final pathology, 85.2% were pN0 and 14.8% were pN1-3. For those with a RS ≤25, 84.9% were pN0, 14.8% were pN1 and 0.3% were pN2-3. For those with a RS &gt;25, 86.8% were pN0, 12.9% were pN1 and 0.3% were pN2-3. Overall, 14.5% demonstrated pN1 disease, of which 12.3% yielded a RS &gt;25. Of the 461 patients with pN2-3 disease for whom RS was available, 12.4% (57 patients) had RS &gt;25. After adjustment, RS &gt;25 was associated with reduced incidence of pN2-3 compared to pN0-1 (OR=0.64, 95% CI 0.47-0.87, p=0.004).

Conclusion: In this population of post-menopausal patients with cT1-T2N0, HR+/HER2- invasive breast cancer and an available RS, almost 86% displayed pN0 or pN1 disease in conjunction with a RS ≤25. Based on the current available literature, less than 5% of cT1-2N0 patients are thought to harbor &gt;pN1 disease. These data add further support, suggesting that this patient population is unlikely to harbor a higher than limited nodal burden given a clinically negative axilla. Though less than 0.5% of the studied patient population demonstrated pN2-3 disease, an important caveat to make is that these patients would not have met criteria for RS, and it’s likely this low number reflects the absence of testing. Given that RS has not been validated for this higher nodal stage, we cannot make recommendations to omit axillary surgery in this cohort of patients. The data presented here provides further rationale for the two large prospective studies addressing whether SLNB could be eliminated in patients with otherwise small HR+/HER2- tumors which are currently ongoing.

Table 1: Pathologic Nodal Staging Based on Recurrence Score

Citation Format: Astrid Botty van den Bruele, Morgan Paul, Samantha M. Thomas, Sarah L. Sammons, Maggie L. DiNome, Jennifer K. Plichta, Akiko Chiba, Laura H. Rosenberger, E Shelley Hwang. Low 21-Gene Recurrence Score Is Not Associated with a High Axillary Nodal Burden in Post-Menopausal Women Presenting with a Clinically Negative Axilla [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 P3-05-20.

Abstract P1-06-02: The effect of race on pathologic complete response rates and overall survival in patients with triple negative breast cancer

Introduction: Despite the recent overall improvement in survival for patients with breast cancer, racial disparities in outcomes persist. While studies have demonstrated that socioeconomic factors and access to treatment play a role, differences in tumor biology may also contribute. Black women are significantly more likely to develop triple negative breast cancer (TNBC), the deadliest of the breast cancer subtypes, with more TNBC patients progressing to incurable, metastatic disease than patients with any other breast cancer subtype. Studies have demonstrated that TNBC patients who achieve a pathologic complete response (pCR), defined as no residual invasive cancer in the breast or lymph nodes after neoadjuvant chemotherapy (NAC), have improved survival. We hypothesize that rates of pCR and overall survival (OS) in patients with TNBC may differ by race/ethnicity, which may account in part for the disparities in outcomes observed. Methods: Adult female patients with stage I-III TNBC diagnosed in 2010-2019 who received NAC followed by surgery were identified from the National Cancer Database (NCDB). Race/ethnicity was defined as Hispanic (H), Non-Hispanic White (NHW), Non-Hispanic Black (NHB), Non-Hispanic Asian (NHA), and Non-Hispanic Other (NHO). pCR was defined as no invasive cancer in either the breast or axilla (ypT0/is,N0) at surgery. Logistic regression was used to estimate the association of race/ethnicity with achievement of pCR after adjustment for covariates. Unadjusted OS was estimated using the Kaplan-Meier method, and the log-rank test was used to compare groups. Cox Proportional Hazards models were used to estimate the association of race/ethnicity and achievement of pCR with OS after adjustment for covariates. Additional interaction and subgroup analyses were also conducted. Results: Of the 40,890 patients identified, 29.8% (n=12,173) demonstrated pCR after NAC. The unadjusted 5-year OS rates for those who achieved pCR were significantly higher compared to patients with no pCR (0.917, 95% CI 0.911-0.923 vs 0.667, 95% CI 0.661-0.673, log-rank p&lt; 0.001). Hispanic patients were more likely to achieve pCR (OR 1.19, 95% CI 1.08-1.31, p=0.001), and NHB patients were less likely to achieve pCR (OR 0.89, 95% CI 0.83-0.95, p=0.001) compared to NHW, even after adjustment. Unadjusted OS was also notably lower for NHB patients compared to every other race group (5-year OS rate: NHB 0.709 vs NHW 0.746 vs NHO 0.771 vs H 0.772 vs NHA 0.816, log-rank p&lt; 0.001); however, this difference did not persist after adjustment for patient and disease factors, including achievement of pCR. Interval from diagnosis to start of chemotherapy (OR 0.95, 95% CI 0.94-0.96, p&lt; 0.001) and duration after chemotherapy start to surgery (OR 1.02, 95% CI 1.02-1.03, p&lt; 0.001) were associated with the odds of achieving pCR. Overall, the effect of achieving pCR on OS did not differ by race/ethnicity (interaction p=0.10). Discussion: Achieving pCR after NAC in patients with TNBC is associated with a significant improvement in OS. Yet, rates of pCR appear to differ based on race/ethnicity, with NHB patients demonstrating significantly lower rates of pCR than NHW patients, which may contribute to the disparities in survival outcomes observed. In addition to addressing socioeconomic factors and access to treatment, further research examining whether biological differences exist based on race that influence response of TNBC to current standard therapies is essential for improving survival outcomes for this disproportionately affected patient population.

Citation Format: Hannah E. Woriax, Samantha M. Thomas, Jennifer K. Plichta, Laura H. Rosenberger, Astrid Botty van de bruele, Akiko Chiba, Gayle DiLalla, Carolyn Menendez, E Shelley Hwang, Maggie L. DiNome. The effect of race on pathologic complete response rates and overall survival in patients with triple negative breast cancer [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 P1-06-02.

Concordance Between Genomic Alterations Detected by Tumor and Germline Sequencing: Results from a Tertiary Care Academic Center Molecular Tumor Board

OBJECTIVE

The majority of tumor sequencing currently performed on cancer patients does not include a matched normal control, and in cases where germline testing is performed, it is usually run independently of tumor testing. The rates of concordance between variants identified via germline and tumor testing in this context are poorly understood. We compared tumor and germline sequencing results in patients with breast, ovarian, pancreatic, and prostate cancer who were found to harbor alterations in genes associated with homologous recombination deficiency (HRD) and increased hereditary cancer risk. We then evaluated the potential for a computational somatic-germline-zygosity (SGZ) modeling algorithm to predict germline status based on tumor-only comprehensive genomic profiling (CGP) results.

METHODS

A retrospective chart review was performed using an academic cancer center's databases of somatic and germline sequencing tests, and concordance between tumor and germline results was assessed. SGZ modeling from tumor-only CGP was compared to germline results to assess this method's accuracy in determining germline mutation status.

RESULTS

A total of 115 patients with 146 total alterations were identified. Concordance rates between somatic and germline alterations ranged from 0% to 85.7% depending on the gene and variant classification. After correcting for differences in variant classification and filtering practices, SGZ modeling was found to have 97.2% sensitivity and 90.3% specificity for the prediction of somatic versus germline origin.

CONCLUSIONS

Mutations in HRD genes identified by tumor-only sequencing are frequently germline. Providers should be aware that technical differences related to assay design, variant filtering, and variant classification can contribute to discordance between tumor-only and germline sequencing test results. In addition, SGZ modeling had high predictive power to distinguish between mutations of somatic and germline origin without the need for a matched normal control, and could potentially be considered to inform clinical decision-making.

Implications of missing data on reported breast cancer mortality

BACKGROUND

National cancer registries are valuable tools to analyze patterns of care and clinical outcomes; yet, missing data may impact the accuracy and generalizability of these data. We sought to evaluate the association between missing data and overall survival (OS).

METHODS

Using the NCDB (National Cancer Database) and SEER (Surveillance, Epidemiology, End Results Program), we assessed data missingness among patients diagnosed with invasive breast cancer from 2010 to 2014. Key variables included demographic (age, race, ethnicity, insurance, education, income), tumor (grade, ER, PR, HER2, TNM stages), and treatment (surgery in both databases; chemotherapy and radiation in NCDB). OS was compared between those with and without missing data using Cox proportional hazards models.

RESULTS

Overall, 775,996 patients in the NCDB and 263,016 in SEER were identified; missing at least 1 key variable occurred for 29% and 13%, respectively. Of those, the overwhelming majority (NCDB 80%; SEER 88%) were missing tumor variables. When compared to patients with complete data, missingness was associated with a greater risk of death: NCDB HR 1.23 (99% CI 1.21-1.25) and SEER HR 2.11 (99% CI 2.05-2.18). Patients with complete tumor data had higher unadjusted OS estimates than that of the entire sample: NCDB 82.7% vs 81.8% and SEER 83.5% vs 81.7% for 5-year OS.

CONCLUSIONS

Missingness of select variables is not uncommon within large national cancer registries and is associated with a worse OS. Exclusion of patients with missing variables may introduce unintended bias into analyses and result in findings that underestimate breast cancer mortality.