DCIS stands for Ductal Carcinoma In Situ which, in plain language, means cancer that has originated from the duct structures of the breast and has stayed “in place.” In DCIS, the cells lining a breast duct lose their regulatory mechanisms and therefore grow and divide inappropriately. This abnormal cell growth is the hallmark feature of cancer and explains why the cells in DCIS are “cancerous.” However, the in situ description designates these cells as in place, which means that they have not invaded into the nearby normal breast tissue as seen in Stages 1 through 4 of breast cancer. While patients with DCIS occasionally present to their doctor with a palpable mass (a mass that can be felt) or nipple discharge, the majority of patients do not have any symptoms and are diagnosed following biopsy performed after an abnormal screening mammogram. With appropriate management, patients with DCIS usually enjoy an excellent prognosis.
DCIS management differs significantly from management of Stages 1 through 4 of breast cancer but similarly requires multi-specialty management including a breast surgeon, radiation oncologist and medical oncologist. DCIS treatment is focused on preventing the development of invasive carcinoma, the spread of cancerous cells outside of the duct and into the surrounding normal breast tissue, at the site of DCIS as well as reducing the patient’s risk for a second diagnosis of an invasive or non-invasive cancer at a different site in either breast. Patients most often undergo a lumpectomy (surgical removal of a part of the breast) but occasionally undergo mastectomy (surgical removal of all of the breast tissue). Mastectomy may be recommended if the area of DCIS is large relative to the patient’s breast size; however, other patient-specific factors also impact the surgical decision-making process. Following lumpectomy, most patients with DCIS receive radiation therapy, which is highly effective at preventing local recurrence near the surgical site.
As a medical oncologist, I frequently meet with patients diagnosed with DCIS after they have already undergone surgery. My responsibility is to determine the best medical strategy to reduce my patient’s risk of developing any subsequent invasive or non-invasive breast cancer in either breast. For patients with DCIS, in particular those with DCIS that expresses the estrogen and progesterone hormone receptors, this typically involves endocrine therapy with an oral medication that targets these receptors. The specific type of endocrine therapy is dependent both on the patient’s menopausal status and other medical conditions. In general, these medications reduce a patients risk for a subsequent diagnosis of invasive or non-invasive breast cancer by approximately 50 percent. Occasionally patients with DCIS may receive endocrine therapy even if their DCIS does not express the estrogen or progesterone receptor if it is felt to be beneficial based on additional patient risk factors. DCIS is not treated with chemotherapy.
During my initial consultation with a new patient, I also discuss any relevant family history and consider genetic testing (if not already performed) if I am concerned for a potential familial genetic predisposition. In addition to medical therapy, on an individual basis, I evaluate whether additional breast imaging (i.e. MRI) should be incorporated into a patient’s breast screening plan. I also routinely discuss lifestyle interventions such as smoking cessation, exercise and weight management for risk reduction that can be considered.
I believe that it is critically important that every patient going through treatment for cancer feels comfortable discussing their concerns with all the members of their medical team. At NYU Winthrop Hospital, I have the privilege of caring for patients with breast cancer alongside a team of highly skilled breast surgeons and radiation oncologists who share a mutual respect for the importance of shared decision-making in management of breast cancer.
To schedule an appointment, or learn more about the NYU Winthrop Breast Health Program, visit www.nyuwinthrop.org or call 1-866-WINTHROP.
Douglas Marks, MD
Dr. Douglas Marks is an Attending Physician in the Division of Oncology/Hematology at NYU Winthrop Hospital, having joined the Hospital following a fellowship program in Oncology/Hematology at Columbia University Medical Center. Dr. Marks also serves as a Clinical Instructor with a primary clinical focus on breast cancer. Dr. Marks was awarded an American Association for Cancer Research (AACR) Scholar in Training Award in 2017 and is currently involved in several research endeavors focused on better understanding the interaction between an individual patient’s immune system and breast cancer.