Long-term rates of ipsilateral breast tumor recurrence (IBTR) for women with ductal carcinoma in situ (DCIS) meeting LORIS trial eligibility criteria undergoing standard therapy.

Abstract

560 Background: Identification of DCIS patients at low risk for progression to invasive carcinoma could obviate the need for standard surgery and radiation therapy (RT). The “Surgery versus Active Monitoring for LOw RISk DCIS [LORIS]” trial is studying the safety of monitoring low-risk DCIS without excision, although IBTR rates in this population undergoing standard therapy are unknown. Methods: Women with DCIS treated with breast-conserving surgery (BCS) with or without RT from 1996-2010 were included from a prospectively maintained database. IBTR rates were compared between those who did and did not meet LORIS eligibility criteria (age ≥46yrs, screen-detected calcifications, non-high grade DCIS diagnosed on needle biopsy, absence of nipple discharge, minimal family history). Results: 2,537 women were identified; 405 met LORIS criteria. LORIS cohort median age was 60yrs (range 46-86yrs); 210 (52%) underwent RT, 81 (20%) received endocrine therapy. Median follow-up was 5.8yrs (range 0-18yrs). 24 experienc...