Treatment Landscape of Ductal Carcinoma In Situ

Major improvements in breast imaging over the last 40 years have led to increased numbers of patients diagnosed with ductal carcinoma in situ (DCIS). Subsequently, after shifting the diagnosis from palpable breast masses to detection of small about 10 mm lesions by mammography, the concept of breast conservative surgery was developed. Therefore, surgical excision and oncoplastic techniques have improved both accuracy of the procedure and subsequent cosmetic result. Approximately 40% of DCIS cases are treated by surgery alone, i.e., local excision, or mastectomy. In addition, radiotherapy and endocrine therapy are recommended for patients after breast conservation. Recently, results from clinical trials investigating the benefit of targeted therapies were reported, however without any meaningful impact on patient outcome. In this review, we summarize our current understanding of the role of conservative surgery in DCIS treatment and present relevant clinical trials in which conservative surgery, radiation, and adjuvant therapies were investigated. We also outline the tumor biology of DCIS in light of recent developments of genetic assays and their potential utility in the clinic.