Postmastectomy radiotherapy and locoregional recurrence rate in high-risk breast cancer patients

Abstract

BACKGROUND: Postmastectomy radiotherapy has been the topic for many debates over several years about its role on locoregional control as well as overall survival in premenopausal and postmenopausal breast cancer patients. METHODS: From 1994 till 1999, 233 patients underwent modified radical mastectomy for breast cancer. Among them there was 92 premenopausal patients (median age was 44 years) and 141 postmenopausal patients (median age was 60 years). Traditional prognostic factors were used to assess risk of locoregional recurrence: 84 patients were node-negative, 71 patients had 1 to 3 lymph nodes positive, and 71 patients had 4 and more positive lymph nodes; 103 patients had tumor less than 3 cm diameter and 130 patients had tumors grater than 3 cm. According to this, postmastectomy radiotherapy was applied in 125 patients of whom 117 patients (94%) had also adjuvant systemic therapy (chemotherapy and/or hormonal therapy). RESULTS: The locoregional recurrence was observed in 42 patients while 191 patients were free of (median follow-up time was 49 months). Locoregional recurrence developed in 10 patients who had postmastectomy radiotherapy and in 32 patients who did not had postmastectomy radiotherapy (p=0.0001). In the group of patients with locoregional recurrence event 5-year overall survival was 28% while 70% in the group of patients free of (p=0.00001). There was statistically significant advantage for postmastectomy radiotherapy in the group of patients with 1 to 3 positive lymph nodes as well as for 4 and more positive lymph nodes group (p=0.0008). In addition there was statistically significant difference among postmastectomy radiotherapy group and no postmastectomy radiotherapy group for disease free survival (74% vs. 50%, 5-year disease free survival, p=0.0001) and overall survival (71% vs. 53%, 5-year overall survival, p=0.0422). CONCLUSION: Postmastectomy radiotherapy reduces locoregional recurrence rate and improves overall survival in premenopausal and postmenopausal breast cancer patients with tumors grater than 3cm diameter and positive axillary lymph nodes.