Locoregional recurrence of triple-negative breast cancer: effect of type of surgery and adjuvant postoperative radiotherapy

Abstract

Yasser Bayoumi,1 Ayman AbdelSamie,2 Ahmed Abdelsaid,3 Aida Radwan4 1Radiation Oncology, 2Medical Oncology, 3Surgical Oncology, 4Medical Physics, National Cancer Institute, Cairo University, Cairo, Egypt Background/purpose: The aim was to evaluate the prognostic significance of postoperative radiotherapy (PORT) and surgical type on local recurrence-free survival (LRFS) and overall survival (OS) in triple-negative breast cancer (TNBC) in the Egyptian population. Patients and methods: We evaluated 111 patients with stage I–III TNBC diagnosed at our institute during the period from 2004 to 2009. Patients were stratified according to PORT into two groups: a PORT group and a non-PORT group. The influence of PORT and surgical type on LRFS and OS were evaluated. A cross-matching was done to the non-TNBC group of patients to compare the recurrence and survival rates between them and the studied group of TNBC patients. Results: The mean age of TNBC patients at diagnosis was 63±7 years. The majority of the patients had stage III disease (68.5%) and 73% had clinical or pathological positive lymph nodes. Sixty percent (67/111) of patients had modified radical mastectomy and 44/111 (40%) patients had breast-conserving treatment. PORT was given for 63% of patients, while systemic treatment was given in 89% of patients. At the time of analysis, 13 patients (11%) developed local recurrence: five of 70 (7%) in the PORT group and eight of 41 (19.5%) in the non-PORT group. Five-year LRFS for the whole group of patients was 88%±6%, which was significantly affected by PORT. The surgical type did not affect local recurrence significantly. Five-year OS for the whole group was 54%±8%. PORT and surgical type did not affect OS significantly (P-value 0.09 and 0.11, respectively). Five-year LRFS was 88%±6% and 90%±11% for TNBC and non-TNBC patients, respectively (P-value 0.8); however, OS for TNBC was significantly lower than for non-TNBC (P-value 0.04). Conclusion: TNBC is an aggressive entity compared with other non-TNBC, and these patients benefit from PORT significantly to decrease the risk of local recurrence in all stages. However, further large, prospective, randomized trials are warranted. Keywords: triple-negative breast cancer, postoperative radiotherapy, local recurrence-free survival, overall survival