Your breast specialist needs certain information about the DCIS to help plan the best treatment for you. This includes:
- the stage of the cancer
- the grade of the cancer
- whether the cancer has certain hormone receptors (see below).
The stage of a cancer describes its size and whether it has spread from where it started.
DCIS is described as stage 0. This is the earliest stage and means there is no invasive breast cancer. DCIS can be any size, but will always be stage 0.
The grade of a cancer describes how the cells look and how quickly they grow compared with normal cells. In DCIS, the grade of the cells is important. It indicates how likely DCIS is to come back in the breast. It also indicates how likely it is to develop into an invasive cancer.
There are three grades:
Grade 1 (low-grade cancer)
The cancer cells look similar to normal cells (they are well differentiated). They usually grow slowly. These cancer cells are less likely to spread.
Grade 2 (moderate or intermediate-grade cancer)
The cancer cells look more abnormal and grow slightly faster than grade 1 cells.
Grade 3 (high-grade cancer)
The cancer cells look very different from normal cells (they are poorly differentiated). They may grow more quickly than grade 1 or 2 cells.
The pathologist will examine the tissue to see whether the cells have started to spread through the walls of the lobules or ducts. These very small areas of spread are called areas of microinvasion.
DCIS cells may have receptors (proteins) on them that allow hormones, such as oestrogen, to attach to the cancer cell. These hormones can help the cancer cells grow. A pathologist tests the tissue that was removed during the biopsy or surgery for oestrogen receptors.
Drugs that reduce levels of oestrogen in the body are called hormonal therapies. If the DCIS is oestrogen receptor-positive (ER-positive), your doctor may suggest taking hormonal therapies to shrink the DCIS before surgery.
Below is a sample of the sources used in our ductal carcinoma in situ (DCIS) information. If you would like more information about the sources we use, please contact us at firstname.lastname@example.org
European Society for Medical Oncology. Primary breast cancer: ESMO clinical practice guidelines for diagnosis, treatment and follow-up. Annals of oncology 26 (supplement 5): v8–v30. 2015.
Morrow M, et al. Chapter 79: malignant tumors of the breast. DeVita, Hellman and Rosenberg’s cancer: principals and practice of oncology (10th edition). Lippincott Williams and Wilkins. 2014.
National Institute for Health and Care Excellence (NICE). Early and locally advanced breast cancer: diagnosis and management. July 2018.
Scottish Intercollegiate Guidelines Network. SIGN 134. Treatment of primary breast cancer: a national clinical guideline. September 2013.
This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Professor J Michael Dixon, Professor of Surgery & Consultant Surgeon.
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