Outcome of long term active surveillance for estrogen receptor-positive ductal carcinoma in situ

IntroductionAn option for active surveillance is not currently offered to patients with ductal carcinoma in situ (DCIS); however a small number of women decline standard surgical treatment for noninvasive cancer. The purpose of this study was to assess outcomes in a cohort of 14 well-informed women who elected non-surgical active surveillance with endocrine treatment alone for estrogen receptor-positive DCIS.MethodsRetrospective review of 14 women, 12 of whom were enrolled in an IRB-approved single-arm study of 3 months of neoadjuvant endocrine therapy prior to definitive surgical management. The patients in this report withdrew from the parent study opting instead for active surveillance with endocrine treatment and imaging.Results8 women had surgery at a median follow up of 28.3 months (range 10.1–70 months), 5 had stage I IDC at surgical excision, and 3 had DCIS alone. 6 women remain on surveillance without evidence of invasive disease for a median of 31.8 months (range 11.8–80.8 months).ConclusionLong-term active surveillance for DCIS is feasible in a well-informed patient population, but is associated with risk of invasive cancer at surgical excision.