Patterns of systemic treatment utilization in ER+/PgR+/HER2+, early-stage breast cancer (BC): An analysis of the National Cancer Database.

Zeina A. Nahleh Cleveland Clinic Florida, El Paso, TX info_outline Zeina A. Nahleh, Brian Hobbs, Elizabeth Elimimian, Wei (Auston) Wei, Annie Gupta, Cassann N. Blake

Authors Zeina A. Nahleh Cleveland Clinic Florida, El Paso, TX info_outline Zeina A. Nahleh, Brian Hobbs, Elizabeth Elimimian, Wei (Auston) Wei, Annie Gupta, Cassann N. Blake Organizations Cleveland Clinic Florida, El Paso, TX, Taussig Cancer Institute and Lerner Research Institute, Cleveland Clinic, Cleveland, OH, Cleveland Clinic Fl, Weston, FL, Cleveland Clinic Foundation, Cleveland, OH, Cleveland Clinic Florida, Weston, FL Abstract Disclosures Research Funding Other Cleveland Clinic Florida-Maroone Cancer Center Background: The preferences and trends of treatment utilization of adjuvant endocrine therapy (ET) versus chemotherapy (CH) for small node-negative triple positive (TP) BC are unclear. We sought to determine these preferences and assess the impact on outcome. Methods: This is a retrospective study from the National Cancer Database including patients with TP stage I BC, 2004-2015. Treatment selection was evaluated for association with patient clinical and demographic characteristics using logistic regression. Overall survival (OS) was estimated using the Kaplan-Meier method and compared among patient and treatment cohorts by log-rank test and Cox regression. Results: Of 37,777 patients analyzed, 79% were White (Non-Hispanics), 10% African Americans, and 5% Hispanic/Latinos. 57% were 50-70 years old. 86% received adjuvant endocrine therapy versus 14% CH first. Around 40 % of all patients received anti-Her2 therapy. Patients younger than 70 years, with male BC, diagnosed with poorly differentiated BC, African Americans and Hispanics were more likely to be treated with chemotherapy. OS rate at 5-year was 92.3% (95% CI: 0.918-0.928). In multivariate analysis for patients with survival data, an increased rate of death was associated with: treatment in community versus academic/research centers, CH first versus ET, no treatment with anti-Her2 therapy, government versus private /no insurance, Native American ethnicity. A slight but statistically significant reduction in the in the risk of death at 5 years was evident for patients receiving anti-Her2 therapy plus ET therapy, 5-year OS 93.5% (CI: 89.2-98%), when compared to patients receiving anti-Her2 therapy plus CH 92.7 % (CI: 89.4-96). Conclusions: This study provides real world data of common practices in the US . The majority of patients with node negative Stage I, ER+/PR+/Her2+ BC received adjuvant ET and anti-Her2 therapy, not chemotherapy. These patients had a similar to slightly improved 5 year- survival when compared to anti-Her2 therapy plus CH, supporting the use ET plus anti-Her2 therapy in this setting. Future studies should focus on better selecting patients with hormone receptor positive and Her 2 + early stage BC who would benefit from adjuvant CH. Disparity in outcome also warrants further evaluation. Level Total N Number of events 5 years OS Years (95%CI) P-value CH , no Anti Her2 2333 159 91.2 (89.7, 92.7) <0.0001 CH + Anti-Her2 1335 56 92.7 ( 89.4, 96.1) ET, no Anti-Her2 17160 904 92.2 (91.6, 92.7) ET + Anti-Her2 7728 93 93.5 ( 89.2, 98)