Differential Prognostic Value of Residual Nodal Burden in Breast Cancer Subtypes.

Purpose: Residual cancer burden (RCB) index after neoadjuvant chemotherapy (NAC) is highly prognostic in patients with breast cancer (BC) but does not account for subtype or the precise impact of residual nodal burden (RNB). We aimed to precisely de ne the effect of RNB on survival by subtypes. Methods: Adult women with non-metastatic BC diagnosed from 2006-2021 in the National Cancer Database (NCDB) who received NAC followed by surgery within 8 months were included. RNB was also evaluated as a predictor of mortality with multivariable logistic regression. Kaplan-Meier analyses were performed to compare overall survival. Results: 51,917 patients were included. After adjustment, ypN stage was the strongest predictor of mortality, with an odds ratio (OR) of 2.24 (95% CI 2.08-2.41) for ypN1 vs ypN0 and increased with increasing nodal burden - ypN2 vs ypN0 OR 5.03, 95% CI 4.60-5.51 and ypN3 vs ypN0 OR 8.85, 95% CI 7.88-9.93. Stratification of survival curves with higher RNB is most pronounced for triple-negative breast cancer (TNBC) with an absolute difference of 64% in 5-year overall survival between ypN0 and ypN3 patients, and lowest for the ER+/HER2- subtype with a 25% absolute difference in 5-year OS between ypN0 and ypN3 patients. On interaction analysis, ypN status was a stronger predictor of mortality for the TNBC subtype compared to other subtypes. Conclusion: RNB has a significantly different impact on survival by BC subtypes. Future study of optimal therapeutic strategies for patients with residual nodal disease after NAC should account for subtype specific differences in prognosis.

Germline genetic mutations in a multi-center cohort of 248 phyllodes tumors.

PURPOSE: Germline genetic mutations in women with phyllodes tumors (PT) are understudied, although some describe associations of PT with various mutations. We sought to determine the prevalence of pathogenic/likely pathogenic (P/LP) variants in women with PT. METHODS: A 6-site multi-center study of women with a PT was initiated, then expanded nationally through an online "Phyllodes Support Group." All women underwent 84-gene panel testing. We defined eligibility for testing based on select NCCN (National Comprehensive Cancer Network) criteria (v1.2022). Logistic regression was used to estimate the association of covariates with the likelihood of a P/LP variant. RESULTS: 274 women were enrolled: 164 (59.9%) through multi-center recruitment and 110 (40.1%) via online recruitment. 248 women completed testing; overall 14.1% (N = 35) had a P/LP variant, and over half (N = 19) of these individuals had a mutation in genes associated with autosomal dominant (AD) cancer conditions. The most common AD genes with a P/LP variant included CHEK2, ATM, and RAD51D. A quarter of participants (23.8%) met NCCN criteria for testing, but we found no difference in prevalence of a P/LP variant based on eligibility (p = 0.54). After adjustment, the presence of P/LP variants was not associated with age, NCCN testing eligibility, or PT type (all p > 0.05). CONCLUSION: Our study demonstrates that 7.7% of women with PT harbor germline P/LP variants in genes associated with AD cancer conditions. Early identification of these variants has implications for screening, risk reduction, and/or treatment. National guidelines for women with PT do not currently address germline genetic testing, which could be considered.

Nodal Response and Survival After Neoadjuvant Endocrine Therapy in Hormone Receptor-Positive Breast Cancer: 20-Year Experience from a Single Institution.

INTRODUCTION: Axillary response to neoadjuvant endocrine therapy (NET) for the treatment of hormone receptor-positive breast cancer (HR+ BC) is not well-described. This study was designed to characterize nodal response after NET. METHODS: Patients receiving NET followed by curative intent surgery at a comprehensive cancer center from 1998 to 2022 in a prospectively collected registry were included. Patients with distant metastasis were excluded. Primary outcome was nodal pathologic complete response (pCR). Downstaging was defined as post-NET decrease in category. RESULTS: We included 123 patients; the majority were cT2 (n = 59) or cT3 (n = 35), and cN0 (n = 81). Median age was 70.0 years (interquartile range 62.1-76.0). Forty-two patients (34.1%) were clinically node-positive. After NET, 73 (59.8%) underwent breast-conserving surgery. All patients underwent sentinel lymph node biopsy, and 12 (9.8%) underwent completion axillary lymph node dissection. In-breast downstaging was achieved in 51 (41.5%) patients, 1 (0.8%) had breast pCR, and 14 (11.4%) had breast upstaging. Axillary downstaging was achieved in 10 (23.8%), 6 patients (14.3%) had nodal pCR, and 14 (33.3%) had axillary upstaging. At 10-year follow-up, local recurrence was 1% and distant recurrence was 14%, while disease-free survival was 82%. After adjusting for demographic and clinical factors, age was the only characteristic associated with mortality (hazard ratio 1.07, 95% confidence interval 1.01-1.13). CONCLUSIONS: In HR+ BC treated with NET, long-term disease-free survival is good, although nodal pCR is uncommon for cN+ patients. Future studies are needed to elucidate optimal neoadjuvant systemic therapy and to delineate oncologically safe strategies to deescalate axillary management for residual microscopic disease.

Omission of Axillary Dissection in Node Positive Breast Cancer After Neoadjuvant Systemic Therapy.

INTRODUCTION: Guidelines recommend axillary lymph node dissection (ALND) for ypN + positive patients as patients receiving neoadjuvant systemic therapy (NST) were excluded from trials omitting ALND in pN + patients. We sought to characterize trends in omission of ALND in patients with ypN + disease. METHODS: Adult women with invasive breast carcinoma in the National Cancer Database between 2012 and 2019 who received NST (chemotherapy or endocrine) and had ypN + disease were included. Patients were excluded if they did not have definitive surgery within eight months of diagnosis. The primary study outcome was completion of ALND versus omission. Differences in demographics, tumor characteristics, and treatment were identified using bivariate and multivariate logistic regression models. RESULTS: In total, 103,121 women were included. Most had cT1 (26%) or cT2 (45%) tumors, cN + disease (71%), and ductal histology (83%). 69% of patients received neoadjuvant chemotherapy and 31% neoadjuvant endocrine without chemotherapy (30% both). ALND was performed in 77% of patients. Omission of ALND became more prevalent each year from 2012 (14%) to 2019 (34%). On multivariate modeling, year of diagnosis, black race, cN status, higher grade, estrogen receptor+/HER2-receptor subtype, and mastectomy were associated with increased prevalence of ALND. Age, Charlson/Deyo comorbidity index score, endocrine versus chemotherapy, and adjuvant radiation were not associated with receipt of ALND. CONCLUSIONS: Despite guidelines recommending ALND, omission is common in patients with ypN + breast cancer after NST. Omission of ALND increased significantly over time and is associated with clinical and demographic factors. Future study is needed to determine the oncologic safety of this approach.

Analysis of Specimen Mammography with Artificial Intelligence to Predict Margin Status.

BACKGROUND: Intraoperative specimen mammography is a valuable tool in breast cancer surgery, providing immediate assessment of margins for a resected tumor. However, the accuracy of specimen mammography in detecting microscopic margin positivity is low. We sought to develop an artificial intelligence model to predict the pathologic margin status of resected breast tumors using specimen mammography. METHODS: A dataset of specimen mammography images matched with pathologic margin status was collected from our institution from 2017 to 2020. The dataset was randomly split into training, validation, and test sets. Specimen mammography models pretrained on radiologic images were developed and compared with models pretrained on nonmedical images. Model performance was assessed using sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). RESULTS: The dataset included 821 images, and 53% had positive margins. For three out of four model architectures tested, models pretrained on radiologic images outperformed nonmedical models. The highest performing model, InceptionV3, showed sensitivity of 84%, specificity of 42%, and AUROC of 0.71. Model performance was better among patients with invasive cancers, less dense breasts, and non-white race. CONCLUSIONS: This study developed and internally validated artificial intelligence models that predict pathologic margins status for partial mastectomy from specimen mammograms. The models' accuracy compares favorably with published literature on surgeon and radiologist interpretation of specimen mammography. With further development, these models could more precisely guide the extent of resection, potentially improving cosmesis and reducing reoperations.

Diversity, equity, and inclusion in genitourinary clinical trials leading to FDA novel drug approval: An assessment of the FDA center for drug evaluation and research drug trials snapshot.

To determine the distribution of race and ethnicity among genitourinary oncology trial participants leading to FDA approval of novel molecular entities/biologics. Secondarily, we evaluated whether the proportion of Black participants in clinical trials increased over time. We quired the FDA Center for Drug Evaluation and Research Drug Trials Snapshot (DTS) between 2015 and 2020 for urologic oncology clinical trials leading to FDA approval of novel drugs. Enrollment data was stratified by race and ethnicity. Cochran-Armitage Trend tests were used to examine changes in Black patient participation over years. Nine clinical trials were identified that led to FDA approval of 5 novel molecular entities for prostate and 4 molecular entities for urothelial carcinoma treatment. Trials for prostate cancer included 5202 participants of which 69.8% were White, 4.0% Black, 11.0% Asian, 3.6% Hispanic, <1% American Indian/Alaska Native or Native Hawaiian/Pacific Islander, 3% other. Trials in urothelial carcinoma had 704 participants of which 75.1% were male, 80.8% White, 2.3% Black, 2.4% Hispanic, <1% American Indian/Alaska Native or Native Hawaiian/Pacific Islander, 5% other. Black participation rates over time did not change for urothelial (P = 0.59) or the combined cancer cohort (P = 0.29). Prostate cancer enrollment trends among Black participant declined over time (P = 0.03). Participants in genitourinary clinical trials leading to FDA approval of novel drugs are overwhelmingly white. Involving stakeholders who represent the needs and interests of underrepresented populations in the design and implementation of clinical trials of novel agents may be a strategy to increase diversity, equity, and inclusion among genitourinary clinical trials.

Computer Vision Analysis of Specimen Mammography to Predict Margin Status.

Intra-operative specimen mammography is a valuable tool in breast cancer surgery, providing immediate assessment of margins for a resected tumor. However, the accuracy of specimen mammography in detecting microscopic margin positivity is low. We sought to develop a deep learning-based model to predict the pathologic margin status of resected breast tumors using specimen mammography. A dataset of specimen mammography images matched with pathology reports describing margin status was collected. Models pre-trained on radiologic images were developed and compared with models pre-trained on non-medical images. Model performance was assessed using sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). The dataset included 821 images and 53% had positive margins. For three out of four model architectures tested, models pre-trained on radiologic images outperformed domain-agnostic models. The highest performing model, InceptionV3, showed a sensitivity of 84%, a specificity of 42%, and AUROC of 0.71. These results compare favorably with the published literature on surgeon and radiologist interpretation of specimen mammography. With further development, these models could assist clinicians with identifying positive margins intra-operatively and decrease the rate of positive margins and re-operation in breast-conserving surgery.

Racial-ethnic variations in phyllodes tumors among a multicenter United States cohort.

BACKGROUND AND OBJECTIVES: Previous studies have identified racial-ethnic differences in the diagnostic patterns and recurrence outcomes of women with phyllodes tumors (PT). However, these studies are generally limited in size and generalizability. We therefore sought to explore racial-ethnic differences in age, tumor size, subtype, and recurrence in a large US cohort of women with PT. METHODS: We performed an 11-institution retrospective review of women with PT from 2007 to 2017. Differences in age at diagnosis, tumor size and subtype, and recurrence-free survival according to race-ethnicity. RESULTS: Women of non-White race or Hispanic ethnicity were younger at the time of diagnosis with phyllodes tumor. Non-Hispanic Other women had a larger proportion of malignant PT. There were no differences in recurrence-free survival in our cohort. CONCLUSIONS: Differences in age, tumor size, and subtype were small. Therefore, the workup of young women with breast masses and the treatment of women with PT should not differ according to race-ethnicity. These conclusions are supported by our finding that there were no differences in recurrence-free survival.

Pathologic complete response and survival after neoadjuvant chemotherapy in cT1-T2/N0 HER2+ breast cancer.

Women with small HER2+ breast cancers may have excellent prognosis with adjuvant single-agent chemotherapy and HER2-targeted therapy. The role of de-escalated therapy in the neoadjuvant setting, however, remains uncertain. We conducted a cohort study of adult women with T1-2/cN0 HER2+ breast cancer diagnosed 2013-2016 in the National Cancer Database treated with neoadjuvant chemotherapy (NAC) and HER2-targeted therapy. Factors associated with pathologic complete response (pCR) and overall survival were examined. In total, 6994 patients were included, 32% cT1 and 68% cT2. Multi-agent NAC was given to 90% of women while single-agent NAC was given to 10% of women. pCR was achieved in 46% of cT2 patients and 43% of cT1, and in 46% of patients treated with multi-agent versus 38% single agent. Patients receiving multi-agent chemotherapy were younger, had fewer comorbidities, and had higher cT stage and grade. In all patients, pCR was associated with improved survival (p < 0.01). Multi-agent chemotherapy (OR 1.3, p = 0.003), hormone receptor negative (OR 2.6, p < 0.001), higher grade (OR 2.2, p < 0.001), younger age (OR 1.4, p = 0.011), and later year of diagnosis (OR 1.3, p = 0.005) were associated with achieving pCR. Multi-agent chemotherapy was associated with higher likelihood of pCR, but this effect was modest compared to other factors. Single-agent NAC with HER2-directed therapy in selected patients may provide excellent outcome with reduced toxicity, while allowing escalated therapy in the adjuvant setting for patients with residual disease. Prospective studies are needed to determine effects of de-escalation in the neoadjuvant setting on survival and optimal selection strategies.

Prospective Evaluation of Radar-Localized Reflector-Directed Targeted Axillary Dissection in Node-Positive Breast Cancer Patients after Neoadjuvant Systemic Therapy.

BACKGROUND: This is a prospective, single-institution study to evaluate feasibility and accuracy of radar-localized reflector (RLR)-targeted axillary dissection (TAD) in node-positive breast cancer patients after neoadjuvant systemic therapy (NST). METHODS: Patients with biopsy-proven T1-2, N1-3 disease were eligible. Before NST, a marker clip and/or RLR was placed into the positive node. After NST, RLR was inserted if not placed previously. All patients underwent RLR TAD followed by axillary lymph node dissection (ALND). Primary end points of the trial were feasibility of RLR TAD and false negative rate (FNR). RESULTS: Between 2017 and 2021, 101 patients with N1-3 disease underwent NST. Five patients withdrew from the study, 1 was ineligible, and there were 9 technical failures, thus our final study cohort comprised 86 patients. RLR TAD was performed with probe guidance and confirmed with intraoperative specimen radiograph. After RLR TAD, ALND was performed. Median number of RLR TAD nodes removed was 2 (range 1-10), and the RLR TAD nodes remained positive in 56 patients. Median number of ALND nodes removed was 18 (range 4-46). Accounting for 9 technical failures, feasibility was 90%. All technical failures occurred with attempted placement of RLR after NST. Feasibility rate was 100% when RLR placement occurred at diagnosis. Of the evaluable 86 patients, RLR TAD accurately predicted axillary status in 83 patients, with FNR of 5.1%. CONCLUSION: We demonstrate high accuracy of RLR TAD, especially when RLR is placed before NST. For patients who present with N1-3 disease, this is another step towards axillary surgery de-escalation strategies.

Sociodemographic and Clinical Predictors of Neoadjuvant Chemotherapy in cT1-T2/N0 HER2-Amplified Breast Cancer.

BACKGROUND: The optimal treatment strategy for small node-negative human epidermal growth factor receptor 2-positive (HER2+) breast cancer remains controversial. Neoadjuvant chemotherapy may risk overtreatment, whereas surgery first fails to identify patients with residual disease in need of escalated adjuvant systemic therapy. We investigated patient characteristics associated with receipt of neoadjuvant chemotherapy. METHODS: Adult women with cT1-T2/N0, HER2+ breast cancer between 2013 and 2017 in the National Cancer Database who underwent surgery within 8 months of diagnosis were included. Patients were classified as receiving neoadjuvant chemotherapy versus a surgery-first approach. We assessed the sociodemographic and clinical predictors of neoadjuvant chemotherapy versus surgery first and associations between neoadjuvant chemotherapy and breast cancer treatments using multivariable regression models. RESULTS: We identified 56,784 women, of whom 12,758 (22%) received neoadjuvant chemotherapy, 29,139 (53%) received adjuvant chemotherapy, 12,907 (24%) received no chemotherapy, and 1980 were missing chemotherapy information. After adjustment, cT2 stage was the strongest predictor of neoadjuvant chemotherapy compared with surgery first. Younger age and later diagnosis year were positively associated with receipt of neoadjuvant chemotherapy. In contrast, hormone receptor positivity, Black race, rural county, and government-funded or no health insurance were inversely associated with neoadjuvant chemotherapy. In multivariable analyses, patients who received neoadjuvant chemotherapy were more likely to have a mastectomy (vs. lumpectomy) and sentinel lymph node biopsy or no nodal surgery (vs. axillary lymph node dissection). Patients who received neoadjuvant chemotherapy were more likely to receive multi-agent (vs. single-agent) chemotherapy than those who received adjuvant chemotherapy. CONCLUSIONS: Substantial differences in the utilization of neoadjuvant chemotherapy exist in women with HER2+ breast cancer, which reflect both clinical parameters and disparities. Optimal treatment strategies should be implemented equitably across sociodemographic groups.

Limited Reporting of Histopathologic Details in a Multi-Institutional Academic Cohort of Phyllodes Tumors: Time for Standardization.

BACKGROUND: Phyllodes tumors are rare fibroepithelial neoplasms that are classified by tiered histopathologic features. While there are protocols for the reporting of cancer specimens, no standardized reporting protocol exists for phyllodes. METHODS: We performed an 11-institution contemporary review of phyllodes tumors. Granular histopathologic details were recorded, including the features specifically considered for phyllodes grade classification. RESULTS: Of 550 patients, median tumor size was 3.0 cm, 68.9% (n = 379) of tumors were benign, 19.6% (n = 108) were borderline, and 10.5% (n = 58) were malignant. All cases reported the final tumor size and grade classification. Complete pathologic reporting of all histopathologic features was present in 15.3% (n = 84) of cases, while an additional 35.6% (n = 196) were missing only one or two features in the report. Individual details regarding the degree of stromal cellularity was not reported in 53.5% (n = 294) of cases, degree of stromal atypia in 58.0% (n = 319) of cases, presence of stromal overgrowth in 56.2% (n = 309) of cases, stromal cell mitoses in 37.5% (n = 206) of cases, and tumor border in 54.2% (n = 298) of cases. The final margin status (negative vs. positive) was omitted in only 0.9% of cases, and the final negative margin width was specifically reported in 73.8% of cases. Reporting of details was similar across all sites. CONCLUSION: In this academic cohort of phyllodes tumors, one or more histopathologic features were frequently omitted from the pathology report. While all features were considered by the pathologist for grading, this limited reporting reflects a lack of reporting consensus. We recommend that standardized reporting in the form of a synoptic-style cancer protocol be implemented for phyllodes tumors, similar to other rare tumors.

FOXA1 and adaptive response determinants to HER2 targeted therapy in TBCRC 036.

Inhibition of the HER2/ERBB2 receptor is a keystone to treating HER2-positive malignancies, particularly breast cancer, but a significant fraction of HER2-positive (HER2+) breast cancers recur or fail to respond. Anti-HER2 monoclonal antibodies, like trastuzumab or pertuzumab, and ATP active site inhibitors like lapatinib, commonly lack durability because of adaptive changes in the tumor leading to resistance. HER2+ cell line responses to inhibition with lapatinib were analyzed by RNAseq and ChIPseq to characterize transcriptional and epigenetic changes. Motif analysis of lapatinib-responsive genomic regions implicated the pioneer transcription factor FOXA1 as a mediator of adaptive responses. Lapatinib in combination with FOXA1 depletion led to dysregulation of enhancers, impaired adaptive upregulation of HER3, and decreased proliferation. HER2-directed therapy using clinically relevant drugs (trastuzumab with or without lapatinib or pertuzumab) in a 7-day clinical trial designed to examine early pharmacodynamic response to antibody-based anti-HER2 therapy showed reduced FOXA1 expression was coincident with decreased HER2 and HER3 levels, decreased proliferation gene signatures, and increased immune gene signatures. This highlights the importance of the immune response to anti-HER2 antibodies and suggests that inhibiting FOXA1-mediated adaptive responses in combination with HER2 targeting is a potential therapeutic strategy.

The Prognostic Value of Axillary Staging Following Neoadjuvant Chemotherapy in Inflammatory Breast Cancer.

BACKGROUND: Inflammatory breast cancer (IBC) has historically been characterized by high rates of recurrence and poor survival; however, there have been significant improvements in systemic therapy. We sought to investigate modern treatment of IBC and define the yield and prognostic significance of axillary lymph nodes after neoadjuvant chemotherapy (NAC). METHODS: Women with clinical stage T4d, N0-N3, M0 IBC from 2012 to 2016 in the National Cancer Database were included. Kaplan-Meier survival curves and Cox regression were used to assess mortality by receptor subtype and nodal status. RESULTS: We identified 5265 patients; 37% hormone receptor (HR) +/HER2 - , 19% HR +/HER2 + , 18% HR -/HER2 + , and 26% triple-negative, and 5-year overall survival was 51.6%. Only 34% were treated according to guidelines with NAC, modified radical mastectomy, and adjuvant radiation. Pathologically positive lymph nodes (ypN +) after NAC varied by subtype and clinical nodal status (cN) ranging from 82% in cN + HR +/HER2 - patients to 19% in cN0 HR -/HER2 + patients. ypN + strongly correlated with survival in all subtypes with the most pronounced impact in HR +/HER2 + patients, with 90% 5-year overall survival in ypN0 versus 66% for ypN + (HR 4.29, 95% CI 1.58-11.70, p = 0.03). CONCLUSIONS: Five-year survival in M0 IBC is 51.6%. Positive nodes after NAC varied by subtype and clinical N status but is sufficiently high and provided meaningful prognostication in all subtypes to support continued routine pathologic assessment. Future study is warranted to identify reliable, less morbid, methods of staging the axilla in IBC patients appropriate for deescalation of axillary surgery.

Contemporary Multi-Institutional Cohort of 550 Cases of Phyllodes Tumors (2007-2017) Demonstrates a Need for More Individualized Margin Guidelines.

PURPOSE: Phyllodes tumors (PTs) are rare breast neoplasms, which have little granular data on margins. Current guidelines recommend ≥ 1 cm margins; however, recent data suggest narrower margins are sufficient, and for benign PT, a negative margin may not be necessary. METHODS: We performed an 11-institution contemporary (2007-2017) review of PT practices. Demographics, surgical, and histopathologic data were captured. Logistic regression was used to estimate the association of select covariates with local recurrence (LR). RESULTS: Of 550 PT patients, the majority underwent excisional biopsy (55.3%, n = 302/546) or lumpectomy (wide excision) (38.5%, n = 210/546). Median tumor size was 30 mm, 68.9% (n = 379) were benign, 19.6% (n = 108) borderline, and 10.5% (n = 58) malignant. Surgical margins were positive in 42% (n = 231) and negative in 57.3% (n = 311). A second operation was performed in 38.0% (n = 209) of the total cohort, including 51 patients with an initial negative margin (82.4% with < 2 mm), and 157 with an initial positive margin, with residual disease only found in six (2.9%). Notably, 32.0% (n = 74) of those with an initial positive margin did not undergo a second operation, among whom only 2.7% (n = 2) recurred. Recurrence occurred in 3.3% (n = 18) of the total cohort (n = 15 LR, n = 3 distant), at median follow-up of 36.7 months. LR (all PT grades) was not reduced with wider negative margin width (≥ 2 mm v < 2 mm: odds ratio [OR] = 0.39; 95% CI, 0.07 to 2.10; P = .27) or final margin status (positive v negative: OR = 0.96; 95% CI, 0.26 to 3.52; P = .96). CONCLUSION: In current practice, many patients are managed outside of current guidelines. For the entire cohort, a wider margin width was not associated with a reduced risk of LR. We do not recommend re-excision of a negative margin for benign PT, regardless of margin width, as a progressively wider surgical margin is unlikely to reduce LR.

Survival Outcomes of Early-Stage Hormone Receptor-Positive Breast Cancer in Elderly Women.

BACKGROUND: Elderly women (≥ 70 years old) form a significant proportion of patients affected by breast cancer (BC); however, the treatment decisions for this patient population are complicated, owing to the presence of comorbidities, limited life expectancy, reduced tolerability of therapy, and limited enrollment in clinical trials. A growing body of evidence suggests equivalent outcomes in elderly patients with hormone receptor-positive early-stage breast cancer receiving primary endocrine therapy only or surgery with subsequent endocrine therapy. Whether these results are reproduced in the larger BC population outside of a clinical trial currently remains unclear. PATIENTS AND METHODS: Women ≥ 70 years old diagnosed with early-stage invasive breast cancer between January 2008 and December 2013 with tumor size T1 or T2, minimal nodal involvement (N0 and N1), and estrogen and/or progesterone receptor positivity who started endocrine therapy within a year of diagnosis were identified using the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked datasets. Endocrine therapy was identified using outpatient prescription fills for anastrozole, exemestane, fulvestrant, letrozole, raloxifene, tamoxifen, and toremifene; the first fill date was used as the treatment initiation date. Surgical intervention included either breast-conserving surgery or mastectomy. Women who received chemotherapy were excluded. Trends in the use of primary endocrine therapy only were assessed using Poisson regression. Multivariable Cox proportional hazard regression was used to estimate the association between undergoing surgery within a year of diagnosis and 5-year all-cause mortality, after adjusting for patient demographics, comorbidities, and clinical cancer characteristics. Similar methods were used to assess 5-year cancer-specific mortality, where noncancer mortality was treated as a competing risk. RESULTS: Overall, 8784 women were included in the analysis: 8006 (91%) received surgery with endocrine therapy and 778 (9%) received primary endocrine therapy alone. The proportion of women not receiving surgery remained consistent between 2008 and 2013 (p = 0.10). The 5-year mortality was 11% (n = 619), and 19% of all deaths were due to cancer causes (n = 117). After adjustment, 5-year mortality was lower among women undergoing surgery (HR 0.59, 95% CI 0.47-0.74, p < 0.0001). Similar results were found when looking at 5-year cancer-specific mortality (HR 0.52, 95% CI 0.30-0.90, p < 0.0001). CONCLUSIONS: Elderly breast cancer patients with early-stage hormone-receptor-positive disease receiving primary surgical intervention plus endocrine therapy may have significantly improved survival than those receiving primary endocrine therapy alone. This study suggests the importance of surgical intervention for elderly breast cancer patients and warrants further investigation and comprehensive geriatric assessment to identify subsets of elderly breast cancer patients who may benefit significantly from surgical intervention.

Surgical Approach to Lymphedema Reduction.

PURPOSE OF REVIEW: For patients who have or may develop lymphedema due to oncologic resection, surgical options are available to prevent and treat this chronic disease. Here, we review the current pathophysiology, classification systems, surgical preventive techniques, and treatment options for lymphedema reduction. RECENT FINDINGS: Preventive surgical techniques, including de-escalation of axillary surgery, sentinel lymph node biopsy (SLNB), axillary reverse mapping (ARM), and lymphedema microsurgical preventive healing approach (LYMPHA), have been shown to reduce the incidence of lymphedema. Water displacement remains the gold standard for measuring limb volume and classification of lymphedema; however, lymphoscintigraphy and ICG lymphography are two novel imaging techniques that are now utilized to characterize lymphedema and guide management. Complete decongestive therapy (CDT) remains the mainstay of treatment. Vascularized lymph node transfer (VLNT) and lymphovenous bypass have shown promising results, particularly in advanced lymphedema stages. Combination therapy, incorporating both surgical and non-surgical approaches to lymphedema, yields best patient outcomes. Lymphedema is a chronic disease wherein management requires a combination of surgical and conservative treatments. Standardization in lymphedema staging, key outcome indicators, and quantitative data will be critical to establish the absolute best practices in lymphedema diagnosis and treatment.

Germline Genetic Mutations in a Multi-center Contemporary Cohort of 550 Phyllodes Tumors: An Opportunity for Expanded Multi-gene Panel Testing.

BACKGROUND: A paucity of data exists regarding inherited mutations associated with phyllodes tumors (PT); however, some are reported (TP53, BRCA1, and RB1). A PT diagnosis does not meet NCCN criteria for testing, including within Li-Fraumeni Syndrome (TP53). We sought to determine the prevalence of mutations associated with PT. METHODS: We performed an 11-institution review of contemporary (2007-2017) PT practice. We recorded multigenerational family history and personal history of genetic testing. We identified patients meeting NCCN criteria for genetic evaluation. Logistic regression estimated the association of select covariates with likelihood of undergoing genetic testing. RESULTS: Of 550 PT patients, 59.8% (n = 329) had a close family history of cancer, and 34.0% (n = 112) had ≥ 3 family members affected. Only 6.2% (n = 34) underwent genetic testing, 38.2% (n = 13) of whom had only BRCA1/BRCA2 tested. Of 34 patients tested, 8.8% had a deleterious mutation (1 BRCA1, 2 TP53), and 5.9% had a BRCA2 VUS. Of women who had TP53 testing (N = 21), 9.5% had a mutation. Selection for testing was not associated with age (odds ratio [OR] 1.01, p = 0.55) or PT size (p = 0.12) but was associated with grade (malignant vs. benign: OR 9.17, 95% CI 3.97-21.18) and meeting NCCN criteria (OR 3.43, 95% confidence interval 1.70-6.94). Notably, an additional 86 (15.6%) patients met NCCN criteria but had no genetic testing. CONCLUSIONS: Very few women with PT undergo germline testing; however, in those selected for testing, a deleterious mutation was identified in ~ 10%. Multigene testing of a PT cohort would present an opportunity to discover the true incidence of germline mutations in PT patients.