The role of chemoradiotherapy in patients with unresectable T4 breast tumors.

Purpose: Unresectable T4 tumors of the breast are usually treated with systemic therapies, while the role of local therapies remains debatable. This study aims to evaluate the effectiveness of chemoradiotherapy as a part of T4 breast cancer treatment, and to assess the role of local radiotherapies in patients with unresectable T4 breast tumors.

Materials/methods: Between February 1998 and June 2010, 39 unresectable T4 breast tumors were treated with chemoradiotherapy at our institutes. Clinical stages included stage IIIB (n = 15), stage IIIC (n = 3), and stage IV (n = 21). Twenty-one cases had undergone previous systemic therapies, whereas the remaining 18 cases reported no history of previous treatment. Radiation doses of 59-66 Gy (median 60 Gy) were administered to the breast in addition to concurrent chemotherapies. Acute adverse effects were assessed on a weekly basis during treatment to 2 weeks after completion of treatment, and were scored by the Common Terminology Criteria for Adverse Events v3.0. Treatment response was assessed at 1 month after completion of chemoradiotherapy. Statistical analysis of survival was calculated using the Kaplan-Meier method.

Results: Chemoradiotherapy was completed in all cases. Greater than grade 3 hematological toxicities were observed with regard to lymphocytes (33%), platelets (8%), neutrophils (3%), and hemoglobin (3%). Greater than grade 3 nonhematologic toxicities included chemoradiation dermatitis (23%) and pneumonitis (5%). Sixteen T4 tumors (41%) achieved complete response, whereas 23 (59%) achieved partial response. All patients were treated with chemotherapy and/or endocrine therapy following chemoradiotherapy. The median follow-up period was 20 months (range 3-96 months). Nineteen patients died because of progressive breast cancer. Infield recurrence or relapse was observed in 11 cases during the course of treatment, but only 3 cases were symptomatic. The 2-year overall local control rate was 73.6%, and the survival rate was 65.9%.

Conclusion: Chemoradiotherapy represents a viable option for local treatment of unresectable T4 breast tumors.