Necessity of Surgery for Low-Risk Ductal Carcinoma In Situ of the Breast

Ductal carcinoma in situ (DCIS) is defined as “a neoplastic proliferation of cells within the ductal-lobular structures of the breast that has not penetrated the myoepithelial basement membrane interface.” DCIS is considered to be a nonobligate precursor to invasive cancer, such that the purpose of therapy is primarily to avoid the occurrence of invasive cancer. To achieve this end, DCIS has historically been treated in the same way as invasive breast cancer: surgery, often followed by radiation and antiestrogen therapy (if the DCIS is hormone receptor positive). Advances in mammography and the increasing use of magnetic resonance imaging for breast cancer screening have led to the detection of smaller, low-risk lesions. Growing evidence suggests that low-risk DCIS is unlikely to develop into invasive cancer, leading to a question of whether DCIS can be managed with active surveillance alone, thereby avoiding treatment-associated morbidity.