Isolated Locoregional Recurrence in Patients with Postmastectomy Adjuvant Therapy for Breast Cancer

Objectives: To determine the predictive risk factors for isolated locoregional recurrence (LRR) in breast cancer patients with postmastectomy adjuvant therapy. Patients and Methods: The impacts of patients’ characteristics, tumor stage, and surgery on LRR were evaluated in patients with breast cancer having postmastectomy adjuvant therapy, according to their risk factors using univariate analysis. Factors influencing LRR-free survival were assessed by Cox regression analysis. Results: Of 368 patients, 28 (7.6%) had isolated LRR. Patients’ characteristics such as age, menopause, surgery, tumor size, stage and differentiation, and hormone receptor status were not attributable to LRR. Upper outer quadrant localization was significantly associated with lower LRR occurrence (p=0.048). Among 245 patients whose surgical margin could be assessed, LRR was detected in 6 (20%) of 30 patients with a close surgical margin, while of 215 patients with normal surgical margin, 13 (6%) developed LRR (p=0.007). Kaplan-Meier analysis revealed that larger tumor (p=0.04), presence of LRR (p=0.00001), closer surgical margin (p=0.0085), stage (p=0.0001), and presence of lymph node metastases (p=0.00001) have significantly negative impacts on patients’ survival. Tumor size, lymph node status, and closer surgical margin were found to be the independent factors influencing LRR-free overall survival. Conclusion: Postmastectomy LRR seemed to have a close relationship with the surgical margin status despite standard adjuvant treatments.