PURPOSE: Sacituzumab govitecan (SG) is approved for the treatment of metastatic triple-negative breast cancer (mTNBC). We report the real-world clinical effectiveness and toxicity data of SG in patients with mTNBC. METHODS: A multi-institution retrospective study of patients with mTNBC treated with SG from January 2021 to May 2023 was conducted. Demographic and clinicopathologic variables were collected. Univariate and multivariate Cox regression models were used for survival analysis. RESULTS: A total of 115 patients were included. The median age at SG initiation was 60 years (range, 31-85). All patients were female; 73 (63.5%) were White and 31 (27.0%) were Black. The median number of previous therapies in the metastatic setting was two (range, 0-8). Sixty-one (56.0%) patients had primary refractory disease. Median relative dose intensity was 92% (range, 33%-100%). Grade 3 or higher adverse events (AEs) were seen in 50.9% of patients, which included neutropenia (35.7%), anemia (27.0%), vomiting (16.5%), fatigue (8.7%), and diarrhea (7.0%). Dose reductions and treatment discontinuation due to AEs were required in 51.3% and 13.2%, respectively. The objective response rate (ORR) was 27.8%. Median overall survival was 9.6 months (95% CI, 7.8 to 12.9) and median progression-free survival (PFS) was 4.8 months (95% CI, 3.6 to 5.9). In patients with human epidermal growth factor receptor 2 (HER2)–low mTNBC who received trastuzumab deruxtecan (T-DXd) after SG, the ORR to T-DXd was 34.8% and median PFS was 7 months (95% CI, 4.6 to 10.1). CONCLUSION: In a real-world cohort of heavily pretreated patients with mTNBC, SG retains its clinical activity. In a subgroup with HER2-low disease, T-DXd continues to demonstrate promising clinical activity after SG, supporting the use of sequential antibody-drug conjugates in this population.

Objective/Background: Progesterone-receptor negativity (PR–) is predictive of adverse outcomes in estrogen receptor-positive (ER+) breast cancer. The Oncotype DX assay provides risk stratification for hormone receptor-positive (HR+) invasive breast cancer; however, the association of PR status and Oncotype DX recurrence scores (RSs) is less clear. Methods: We designed an analysis to determine whether a significant difference exists in the RS for ER+/PR– tumors when compared with ER+/PR+ breast cancer. Three hundred and fifty patients with HR+ invasive breast cancer who underwent Oncotype DX testing at our institution from December 2006 to October 2013 were included. We also examined the concordance in the HR status reported by immunohistochemical (IHC) and reverse transcriptase-polymerase chain reaction (RT-PCR) analyses. The data were analyzed by analysis of variance, F test, t test, and chi-square tests. Multivariate linear regression was used to determine significant predictors of Oncotype DX RS. Results: A total of 301 patients had ER+/PR+ tumors and 47 patients had ER+/PR– tumors by IHC. PR– tumors had a significantly higher RS than PR+ tumors (24.7 ± 8.53 vs. 17.3 ± 7.38; p < .001), predicting a greater 10-year risk of distant recurrence. Multivariate linear regression showed PR status and tumor grade to be significant predictors of Oncotype DX RS (p < .0001). A total of 284 patients had HR status reported by Oncotype DX assay. Concordance between IHC and RT-PCR was 99.3% for ER and 88.7% for PR. Conclusion: Our study shows that ER+/PR– breast cancer tumors are associated with a significantly higher Oncotype DX scores; this interprets into a higher risk of recurrence. Our data also show that the concordance between IHC and RT-PCR was 99.3% for ER and lower at 88.7% for PR.

Studies have shown that breast cancer treatment can cause an increase in weight. Weight gain during chemotherapy is usually significant and may be associated with poor survival. However, the role of third- generation chemotherapy regimens and weight gain is not well reviewed. We retrospectively analyzed the mean percentage weight change during the first year after breast cancer diagnosis in 246 patients at West Virginia University during September 2007 and October 2010. Kruskal-Wallis test and post hoc pairwise comparisons were used to assess the influence of age, histology, stage, ER/PR/HER2/neu status, menopausal status, and types of therapeutic modalities received on the percentage weight change. Kaplan-Meier method with log-rank test was used to evaluate recurrence-free survival (RFS). Local or distant recurrence and disease progression were events for RFS analysis and disease-free patients were censored at last follow-up. Mean weight gain was 0.39% (SD, 0.40) of baseline body weight, 1 year after diagnosis of breast cancer. Premenopausal status was the only factor associated with significant weight gain (+1.67% vs -0.10% for postmenopausal patients; P = .02). Stages ≥ III was associated with significant weight loss (-1.64% for stages III, IV vs +0.85% for stages 0, I, II; P = .02) and a lower RFS at 3 years and 5 years (P < .0001). Higher baseline weight (> 90th percentile) did not have any significant impact on RFS (0.84 vs 0.91; P = .19). There was no significant change in weight relative to other factors. Our study in patients receiving third-generation adjuvant chemotherapy regimens did not show any significant change in percentage weight with chemotherapy. Premenopausal status was the only significant factor associated with weight gain. As expected, stage III or higher disease was associated with significant weight loss and lower RFS.