Pattern and Predictors of Locoregional Failure in Locally Advanced Breast Cancer Following Neoadjuvant Chemotherapy and Modified Radical Mastectomy with or without Radiotherapy: Retrospective Cohort Analysis of Patients in a Tertiary Hospital Breast Cente
Objective. The study aimed to identify the pattern and clinicopathologic factors associated with locoregional failure (LRF) in locally-advanced breast cancer (LABC) patients who received neoadjuvant chemotherapy (NAC) and modified radical mastectomy (MRM) with or without adjuvant radiotherapy (RT).
Methods. Retrospective cohort analysis of LABC patients who developed LRF following NAC and MRM with or without RT in the Breast Care Center, Philippine General Hospital from 2007-2010 was done. Clinicopathologic and treatment factors were compared between patients who developed and did not develop recurrence using Student's t-tests and Chi-square tests and logistic regression analysis, with p values ≤0.05 considered significant.
Results. A total of 63 patients were included, 34 with locoregional recurrence (LR) and 29 without. Two-year locoregional recurrence rate (LRR) was 54% with mean time to recurrence at 263 days and chest wall as most common site. Simple logistic regression analysis showed age distribution, pathologic nodal status (pN), percentage positive pathologic lymph nodes, pathologic stage, lymphovascular invasion, and adjuvant RT to be predictors of LR. Furthermore, pN (OR 1.31, CI 1.07-1.59, p=0.01) and adjuvant RT (OR 0.14, CI 0.04-0.53, p=0.004) were independent predictors of LR on multiple logistic regression analysis. In the subset of patients without adjuvant RT, no independent predictor of LR was found on multiple logistic regression analysis.
Conclusion. Among patients with LABC who received NAC and MRM, locoregional recurrence occurred frequently, usually in the chest wall and within a year of treatment. The absence of adjuvant radiotherapy and increased number of positive pathologic lymph nodes were predictive of locoregional recurrence.