Background: 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).
Methods: A prospective database was queried to identify women 18 years of age or older treated for DCIS from 2002 to 2013.
Results: 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.
Conclusions: 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.