Radiotherapy cuts recurrence in ductal carcinoma in situ

Radiotherapy after local excision of ductal carcinoma in situ (DCIS) of the breast reduces the risk of local recurrence for up to 10 years, according to results from a European Organisation for Research and Treatment of Cancer trial.

Nina Bijker, MD, PhD, of The Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital in Amsterdam, and colleagues randomly assigned 1,010 women who underwent a complete local excision of DCIS to either no treatment or radiotherapy at 50 Gray, and followed both groups for a median of 10.5 years to measure recurrence rates.

The investigators found that 85% of women treated with local excision and radiotherapy were disease-free at 10 years compared to only 74% of women treated with surgery alone. Besides only having local excision, additional risk factors for local recurrence were young age, symptomatic detection, intermediate or poorly defined DCIS, cribriform or solid growth pattern, and doubtful margin.

Bijker N, Meijnen P, Peterse JL, et al. Breast-conserving treatment with or without radiotherapy in ductal carcinoma-in-situ: ten-year results of European Organisation for Research and Treatment of Cancer randomized phase III trial 10853-a study by the EORTC Breast Cancer Cooperative Group and EORTC Radiotherapy Group. J Clin Oncol. 2006;24:3381-3387.