Long-term outcomes and risk profile of cT3N0 breast cancer treated with neoadjuvant chemotherapy and curative surgery.

Introduction: We evaluated the treatment outcomes and failure patterns in cT3N0 breast cancer patients classified for rigorous pretreatment evaluation and treated with neoadjuvant chemotherapy (NAC) and curative surgery.

Methods: We reviewed the records of 87 cT3N0 breast cancer patients who received NAC and curative surgery between 2000 and 2015. The clinical high-risk group was defined as having two or more risk factors: age < 40, histologic grade 3, lymphovascular invasion, hormone receptor negativity, and Ki-67 labeling index >20%.

Results: Of the patients, 84 (96.6%) and 79 (90.8%) were initially evaluated using magnetic resonance imaging and positron emission tomography/computed tomography. Most patients received anthracycline based NAC regimen (n = 69, 79.3%) and modified radical mastectomy (n = 61, 70.1%). During a 91.5-month median follow-up, ten patients experienced distant metastasis (DM) only, two had isolated local recurrence, one had local recurrence and DM, and another had local recurrence, regional recurrence, and DM. The 5-year rates of locoregional recurrence, DM, any recurrence (AR), and overall survival (OS) were 1.2%, 11.6%, 11.6%, and 90.8%, respectively. The risk group was an independent prognostic factor of recurrence, and the high-risk group had worse rates of DM (19.2% vs. 0%, P = 0.009), AR (19.2% vs. 0%, P = 0.016) and OS (82.8% vs. 100%, P = 0.001).

Conclusion: Patients with cT3N0 breast cancer classified for rigorous pretreatment evaluation and treated with NAC and radical surgery had favourable oncological outcomes. A clinical risk group based on clinical and immunohistochemical risk factors was an excellent predictor of survival and recurrence.