Nodal pCR and overall survival following neoadjuvant chemotherapy for node positive ER+/Her2- breast cancer.

PURPOSE: The role of neoadjuvant chemotherapy (NAC) in node-positive (N+) ER+/HER2- breast cancer (BC) is debated, given low total pathologic complete response (pCR) rates. However, the rate and impact of nodal pCR is unknown. We sought to evaluate nodal pCR rates and the impact on overall survival (OS). Further, we sought to validate the association between nodal pCR with age and Ki67. METHODS: We queried the National Cancer Database for cN + ER+/HER2- BC patients treated with NAC and surgery. Data from 2010 to 2018 were used to evaluate nodal pCR and OS, with multivariable Cox proportional hazards modeling for OS, as well as Ki67 for the years 2018-2019. RESULTS: From 2010 to 2018, we identified 19,611 cN + ER+/HER2- BC patients treated with NAC. While total pCR occurred in only 7.4%, nodal pCR rates were nearly double (14.3%). Nodal pCR (+/- breast pCR) was seen in 21.7% and associated with 5-year OS rate of 86.1% (95% CI: 84.9-87.4%) versus 77.1% (95% CI: 76.3-77.9%) in patients without nodal pCR (p < 0.001). On multivariable analysis, nodal pCR had better OS (adjusted HR 0.57, 95% CI 0.52-0.63, p < 0.001) across all age groups. Of 2,444 patients with available Ki67, those with age < 50 and Ki67 ≥ 20% had the highest nodal pCR at 31.6%. CONCLUSION: In cN + ER+/HER2- BC treated with NAC, nodal pCR is common, associated with age and Ki67, and prognostic for OS. These data strongly suggest that for cN + patients, eradication of nodal disease is critical for OS, and total pCR may not be the optimal measure of NAC benefit.

Tumor Characteristics of Bilateral Breast Cancer Compared with Unilateral Breast Cancer.

BACKGROUND: Bilateral breast cancer (BC) has an incidence of 1 to 3 %. This study aimed to describe the clinicopathologic characteristics and management of bilateral BC, estimate disease-free survival (DFS), and compare DFS with unilateral BC. METHODS: A retrospective analysis was performed for patients who had bilateral invasive BC or unilateral invasive BC and contralateral ductal carcinoma in situ (DCIS) treated at Mayo Clinic Rochester from 2008 to 2022. A 4:1 matched cohort of patients with unilateral invasive BC was used for comparison. The groups were compared using Wilcoxon rank-sum or chi-square tests. Disease-free survival was analyzed using the Kaplan-Meier method and log-rank test, with Cox proportional hazards regression used for multivariable analysis. RESULTS: The study identified 278 cases of bilateral breast cancer (177 cases of bilateral invasive cancer and 101 cases of unilateral invasive cancer with contralateral DCIS), representing 4.1 % of invasive BCs. Biologic subtype was concordant between sides in 79.8 % of the patients. Initial surgery was bilateral mastectomy for 76.6 %, bilateral lumpectomy for 20.5 %, and unilateral mastectomy with unilateral lumpectomy for 2.9 % of the patients. Pathogenic variants in breast cancer predisposition genes were present in 21.7 % of those tested. The patients who had bilateral BC presented with a higher cT category than the patients who had unilateral BC (p = 0.02), and a higher proportion presented with ILC (17.3 % vs 10.9 %; p = 0.004), estrogen receptor-positive (ER+) disease (89.2 % vs 84.2 %; p = 0.04), multicentric/multifocal disease (37.1 % vs 24.3 %; p < 0.001), breast cancer pathogenic variant (21.7 % vs 12.4 %; p = 0.02), and palpable presentation (48.2 % vs 40.8 %; p = 0.03). The patients with bilateral BC showed DFS similar to that for the unilateral BC cohort (p = 0.71). CONCLUSIONS: Bilateral BCs most commonly are biologically concordant between sides. Bilateral BC presented more commonly with larger tumors, lobular histology, ER+ status, multicentricity or multifocality, pathogenic variant, and palpable disease. Bilateral BC is not associated with worse DFS than unilateral BC.

Repeat sentinel lymph node surgery for locally recurrent breast cancer after prior mastectomy.

BACKGROUND AND OBJECTIVES: Current NCCN guidelines discourage repeat sentinel lymph node (SLN) surgery in patients with local recurrence (LR) of breast cancer following prior mastectomy. This study addresses the feasibility and therapeutic impact of this approach. METHODS: We identified 73 patients managed with repeat SLN surgery for post-mastectomy isolated LR. Lymphatic mapping was performed using radioisotope with or without lymphoscintigraphy and/or blue dye. Successful SLN surgery was defined as retrieval of ≥1 SLN. RESULTS: SLN surgery was successful in 65/73 (89%), identifying a median of 2 (range 1-4) SLNs, with 10/65 (15%) SLN-positive. Among these, 5/10 (50%) proceeded to ALND. In unsuccessful cases, 1/8 (13%) proceeded to ALND. Seven of 10 SLN-positive patients and 50/55 SLN-negative patients received adjuvant radiotherapy. Chemotherapy was administered in 31 (42%) and endocrine therapy in 50 of 57 HR+ patients (88%). After 28 months median follow-up, eight patients relapsed with the first site local in two, distant in five, and synchronous local/distant in one. No nodal recurrences were observed. CONCLUSIONS: SLN surgery for patients with LR post-mastectomy is feasible and informative. This approach appears oncologically sound, decreases axillary dissection rates and may be used to tailor adjuvant radiation target volumes and systemic therapies.

Clinical Behavior, Management, and Treatment Response of Estrogen Receptor Low (1-10%) Breast Cancer.

INTRODUCTION: Estrogen receptor (ER) and progesterone receptor (PR) guide management and impact outcomes of breast cancer (BC). This study compares ER-low (1-10%) with ER-negative (< 1%) and ER-positive (>10%) BC and investigates the significance of PR expression within ER-low disease. PATIENTS AND METHODS: All patients with HER2-negative invasive BC were identified from the National Cancer Database 2018-2019. Treatment and outcomes were compared using chi-squared tests and multivariable logistic regression. RESULTS: Of 232,762 patients, ER expression was: negative (13.8%), low (2.0%), and > 10% (84.2%). Chemotherapy was given in 83.9% of ER- disease, 82.4% of ER-low/PR- disease, 58.9% of ER-low/PR+ disease, and only in 22.9% of ER+ disease. Within the ER-low subgroup, adjuvant endocrine therapy, recurrence score, and Ki67 varied by PR status (all < 0.01). Patients with ER-low disease selected for neoadjuvant chemotherapy (NAC) were younger and had higher T and N category, tumor grade, and Ki67. With NAC, pathological complete response (pCR) rates were similar between ER-low/PR- and ER-low/PR+ (39.5% and 38.1%, respectively, p = 0.67), and were closer to the ER- group (39.7%) than the ER+ group (8.4%). On multivariable analysis, the adjusted effect of ER status (1-10% versus > 10%) on chemotherapy administration was odds ratio (OR) 8.2 (95% CI 7.3-9.2, p < 0.001) for PR-negative, and OR 3.3 (95% CI 7.3-9.2, p < 0.001) for PR-positive. CONCLUSIONS: This study suggests that the tumor features and clinical management of ER-low tumors vary significantly by PR expression. Within ER-low tumors, PR- tumors more closely resemble ER- BC, while PR+ tumors exhibit less aggressive characteristics. In ER-low disease selected for treatment with NAC, response is similar to ER- regardless of PR status.

MYC Targets Scores Are Associated with Cancer Aggressiveness and Poor Survival in ER-Positive Primary and Metastatic Breast Cancer.

MYC is one of the most studied oncogenes that is known to promote cell proliferation. We utilized MYC targets v1 and MYC targets v2 scores of gene set variation analysis and hypothesized that these scores correlate with tumor aggressiveness and survival outcomes. We examined a total of 3109 breast cancer patients from TCGA, METABRIC, and GSE124647 cohorts. In each cohort, the patients were divided into high- and low-score groups using the upper third value as the cut off. As expected, higher scores were related to increased cell proliferation and worse clinical and pathologic features. High MYC targets scores were associated with worse survival, specifically in primary ER-positive breast cancer, consistently in both TCGA and METABRIC cohorts. In ER-positive breast cancer, high MYC targets v1, but not v2 score, was associated with high mutation load, and high MYC targets v1 and v2 scores were both associated with increased infiltration of pro- and anti-cancerous immune cells. We found that high MYC scores were associated with worse survival in metastatic breast cancer. Our findings show that the MYC targets v1 and v2 scores are associated with tumor aggressiveness and poor prognosis in ER-positive primary tumors, as well as in metastatic breast cancer.

Simulation-Based Medical Education: Development of an Assessment Tool for Novice Use.

BACKGROUND: Simulation-based medical education, an educational model in which students engage in simulated patient scenarios, improves performance. However, assessment tools including the Oxford Non-Technical Skills (NOTECHS) scale require expert assessors. We modified this tool for novice use. METHODS: Medical students participated in 5 nontechnical simulations. The NOTECHS scale was modified to allow for novice evaluation. Three novices and 2 experts assessed performance, with intraclass correlation used to assess validity. RESULTS: Twenty-two learners participated in the simulations. Novice reviewers had moderate to excellent correlation among evaluations (0.66 < intraclass correlation coefficients [ICC] < 0.95). Novice and expert reviewers had moderate to good correlation among evaluations (0.51 < ICC < 0.88). DISCUSSION: The modified NOTECHS scales can be utilized by novices to evaluate simulation performance. Novice assessment correlates with expert review. These tools may encourage the use of simulation-based medical education.

Immune cytolytic activity is associated with reduced intra-tumoral genetic heterogeneity and with better clinical outcomes in triple negative breast cancer.

Evaluation of the functional aspects if the tumor immune microenvironment (TIME), such as the recently introduced cytolytic activity score (CYT) index have been under the spotlight in cancer research; however, clinical relevance of immune cell killing activity in breast cancer has never been analyzed in large patient cohorts. We hypothesized that CYT reflects the immune activity of TIME and can predict patient survival. A total of 7533 breast cancer patients were analyzed as both discovery and validation cohorts. We found that high CYT was associated with advanced histological grade and triple-negative breast cancer (TNBC). High CYT in tumors was significantly associated with better survival in TNBC, but unexpectedly, not in other breast cancer subtypes. High CYT TNBC included both favorable immune-related, as well as unfavorable (suppressive) inflammation-related gene sets, and characterized by high infiltration with T cells and B cells. High CYT TNBC was associated with high homologous recombination deficiency and low somatic copy number alteration score and less mutant allele tumor heterogeneity, but not with tumor mutation burden (TMB). Although CYT was not associated with pathological complete response after neoadjuvant chemotherapy, it was significantly associated with high expression of multiple immune checkpoint molecules. In conclusion, CYT of TNBC is associated with enhanced anti-cancer immunity, less intra-tumoral heterogeneity, and with better survival.