Ductal carcinoma in situ is an early form of cancer, or stage 0 breast cancer, according to WebMD. DCIS is the abnormal growth of cells within the breast ducts. Doctors deem it a noninvasive cancer curable with radiation therapy or surgery to preserve the natural breast.
Breast pain or bloody discharge from the nipple are possible initial signs of DCIS, as WebMD explains. A doctor usually cannot feel a lump upon examination. Mammograms detect most cases of DCIS, and a biopsy confirms the diagnosis. Appropriate treatment cures the majority of women who receive a diagnosis of DCIS. Although DCIS is noninvasive, women must undergo treatment because it can be a precursor of a more serious form of cancer.