Conservative Surgery in cT4 Breast Cancer: Single-Center Experience in the Neoadjuvant Setting.

BACKGROUND: The diffusion of screening programs has resulted in a decrease of cT4 breast cancer diagnosis. The standard care for cT4 was neoadjuvant chemotherapy (NA), surgery, and locoregional or adjuvant systemic therapies. NA allows two outcomes: 1. improve survival rates, and 2. de-escalation of surgery. This de-escalation has allowed the introduction of conservative breast surgery (CBS). We evaluate the possibility of submitting cT4 patients to CBS instead of radical breast surgery (RBS) by assessing the risk of locoregional disease-free survival, (LR-DFS) distant disease-free survival (DDFS), and overall survival (OS). METHODS: This monocentric, retrospective study evaluated cT4 patients submitted to NA and surgery between January 2014 and July 2021. The study population included patients undergoing CBS or RBS without immediate reconstruction. Survival curves were obtained using the Kaplan-Meyer method and compared using a Log Rank test. RESULTS: At a follow-up of 43.7 months, LR-DFS was 70% and 75.9%, respectively, in CBS and RBS (p = 0.420). DDFS was 67.8% and 29.7%, respectively, (p = 0.122). OS was 69.8% and 59.8%, respectively, (p = 0.311). CONCLUSIONS: In patients with major or complete response to NA, CBS can be considered a safe alternative to RBS in the treatment of cT4a-d stage. In patients with poor response to NA, RBS remained the best surgical choice.