Ductal carcinoma in situ (DCIS) is a condition characterized by abnormal cells in the milk ducts of the breast. It is called “in situ” (which means "in place") because the cells have not left their original location to invade the surrounding breast tissue. It can also be called intraductal carcinoma as the abnormal cells are found within the milk ducts. DCIS is a non-invasive breast cancer (you may also hear the term “pre-invasive breast carcinoma”). However, without treatment, the abnormal cells could in time turn into invasive cancer. Overall, it's estimated that about 20 to 30 percent of women with untreated, low grade DCIS go on to develop invasive cancer [61]. It is thought that a larger percentage of higher grade DCIS could turn into invasive cancer if left untreated. For more on breast cancer risk factors, see the Risk Factors and Prevention Section.
At this time, health care providers cannot predict which cases of DCIS will progress to invasive cancer and which will not. Therefore, surgery with or without radiation therapy is recommended for the treatment of all DCIS. Prognosis is usually excellent.
Treatment guidelines for DCIS
Although the exact treatment for DCIS varies from person to person, several organizations have guidelines to help ensure quality care. These guidelines are based on the latest research, and some are available online. The American Society of Clinical Oncology (ASCO) and National Comprehensive Care Network (NCCN) are two respected organizations that regularly update and post their guidelines online. The National Cancer Institute (NCI) also has overviews of treatment options.
Updated 01/22/10
