Trends in Treatment Patterns and Clinical Outcomes in Young Women Diagnosed With Ductal Carcinoma In Situ.

BACKGROUND: Although it is known that the risk of a second breast cancer event among young women diagnosed with ductal carcinoma in situ (DCIS) is higher than in older women, the effect of current treatment options on long-term outcomes in this subgroup of women remains poorly defined. We aimed to evaluate national treatment trends and determine their effect on second breast cancer risk and overall survival among young women diagnosed with DCIS.

MATERIALS AND METHODS: Surveillance, Epidemiology, and End Results data from 1998 to 2011 were used to analyze 3648 DCIS patients younger than age 40 years.

RESULTS: Among all treatment options, breast-conserving surgery (BCS) with radiation therapy (BCS + RT) was the most prevalent (36.1%) followed by mastectomy (MTX) without contralateral prophylactic MTX (CPM; 25.8%), BCS alone (22.2%), and MTX with CPM (15.8%). Risk of a second ipsilateral event was > 5-fold and > 2-fold lower within 2 years and 5 years of initial DCIS diagnosis, respectively, in women who received BCS + RT compared with BCS alone; and overall survival was 3-fold higher in women who received BCS + RT. However, MTX with or without CPM did not show an increase in overall survival compared with BCS + RT. In addition, although the percentage of young women who receive MTX with CPM has increased in recent years, MTX with CPM did not show an increased benefit in survival compared with MTX without CPM.

CONCLUSION: The results of our study suggest that more aggressive treatments do not offer survival benefits over BCS + RT; thus, clinical treatment options in young women with DCIS should be carefully considered.