ABSTRACT
Objective To investigate the efficacy,toxicity and cosmetic outcome of short-course radiotherapy with concomitant tumor bed boost after breast-conserving surgery for early stage breast cancer.Methods A total of 306 patients with T1-2 N0-1 M0 breast cancer after breast-conserving surgery were included.160 patients received whole-breast radiation to 45 Gy in 25 fractions followed by tumor bed boost of 14 Gy in 7 fractions (C group).146 patients received whole-breast radiation to 46 Gy in 23 fractions with concomitant tumor bed boost to 60 Gy in 23 fractions (S group).Kaplan-Meier method was used to calculate the local recurrence and overall survival rates and the differences were compared by Logrank test.Chi-square test was used to compared the differences of the clinical characteristics,toxicity and cosmetic outcome between the two groups.Results The follow-up rate was 100％.After a median follow up of 26 months,the 1-,2-and 3-year overall survival rates were 100％.No patient developed local recurrence.In C and S group,the incidence of grade 1 acute skin toxicity was 46.9％ and 45.1％ (x2 =0.73,P =0.695),grade 2was 16.3％ and 13.7％ (x2 =0.73,P =0.695).Grade 1 late skin and subcutaneous tissue toxicity developed in 16.9％ and 17.1％ of patients in C and S group (x2 =0.00,P =0.954).Grade 1 neutropenia occurred in 11.9％ and 13.7％ of patients in C and S group (x2 =0.23,P =0.633).In C and S group,66.2％ and 65.5％ of patients had excellent and good cosmetic outcome (x2 =0.01,P =0.927).Conclusions Short-course radiotherapy with concomitant tumor bed boost provides similar results to conventional radiotherapy in local control,toxicity and cosmetic outcome.Long-term follow up is warranted to confirm this finding.