Multidisciplinary Shared Decision Making in the Management of Ductal Carcinoma In Situ of the Breast.

Abstract

Controversy continues regarding the use of adjuvant radiation therapy (RT) and hormonal therapy (HT) for patients undergoing breast-conserving therapy (BCT) for ductal carcinoma in situ (DCIS). A prospective database was queried to identify women 18 years of age or older treated for DCIS from 2002 to 2013. BCT was completed for 300 patients with a median age of 66 years. The median DCIS size was 0.7 cm (range 0.1-6.0 cm). The DCIS grades were high (44 %), intermediate (37 %), and low (19 %). The closest margin was wider than 3 mm in 80 % and wider than 5 mm in 63 % of the cases. Adjuvant RT was administered to 183 patients (61 %), and the RT status of 9 patients (3 %) was unknown. RT was associated with age, DCIS size, comedo necrosis, grade, and treatment in 2002-2007 versus 2008-2013. Adjuvant HT was administered to 86 estrogen receptor-positive patients (39 %), and the HT status of 4 patients (2 %) was unknown. The median follow-up period was 63 months (range 4-151 months). The 5-year overall local recurrence (LR) rate was 4 % (95 % confidence interval [CI] 2.1-7.4 %). The 5-year LR rate was 3.9 % (95 % CI 1.8-8.6 %) for the RT patients and 4.1 % (95 % CI 1.6-10.7 %) for the patients not receiving RT. Of 13 LRs, 10 (77 %) were DCIS, and 3 (23 %) were invasive including one node-positive recurrence. Multidisciplinary and joint decision making in the treatment of DCIS results in a substantial and increasing number of patients forgoing adjuvant RT, adjuvant HT, or both. Reasonable 5-year LR rates suggest that such decision making can appropriately allocate patients to adjuvant therapies.