Together, you and your doctor will develop a treatment plan for medullary carcinoma. Some doctors feel that a true medullary carcinoma may only require surgery without any additional (or adjuvant) treatments, such as chemotherapy or radiation therapy. This is because medullary carcinoma is usually a small tumor that is not aggressive and rarely spreads to the lymph nodes.
Other doctors believe that all cases of medullary carcinoma should be treated like invasive ductal carcinoma. True medullary carcinoma is quite rare and very difficult to diagnose with certainty, and some doctors may want to make sure they are not under-treating the cancer.
Atypical medullary carcinoma would receive the same treatments as invasive ductal carcinoma.
You can work with your doctor to come up with the treatment plan that is right for you, based on the features of the cancer such as tumor size, grade, and whether or not the cancer has spread to any lymph nodes. Your plan may include:
Surgery to remove the cancer and, if necessary, any affected lymph nodes. If medullary carcinoma spreads to the lymph nodes, it usually involves no more than 3 nodes. Possible procedures are:
- Lumpectomy: The surgeon removes only the part of your breast containing the tumor (the “lump”) and some of the normal tissue that surrounds it. Your surgeon may also remove some lymph nodes.
- Total or simple mastectomy: Removal of the breast without removal of the axillary (underarm) lymph nodes. A sentinel node biopsy may be performed to check the node or nodes closest to the tumor for any signs of cancer spread.
- Modified radical mastectomy: Surgery to remove the breast, the lining of the chest wall muscle, and some of the lymph nodes under the arm.
- Chemotherapy: Chemotherapy involves taking anti-cancer medicines in the form of a pill or directly into a vein. The medicines travel through the bloodstream to all parts of the body. The main goal is to destroy any cancer cells that may have broken away from the original tumor.
- Radiation therapy: Radiation therapy, also called radiotherapy, directs high-energy waves at the area of the body affected by the cancer, such as the chest or the underarm lymph nodes. This directed radiation can destroy any cancer cells that may be left behind.
Most medullary carcinomas test negative for estrogen and progesterone receptors. Therefore, they usually cannot be treated with hormonal therapies such as tamoxifen or aromatase inhibitors, which interfere with estrogen’s ability to promote cancer cell growth. Medullary carcinomas also usually test negative for HER2 receptors, so cannot be treated with anti-HER2 medicines such as Enhertu (chemical name: fam-trastuzumab-deruxtecan-nxki), Herceptin (chemical name: trastuzumab), Kadcyla (chemical name: T-DM1 or ado-trastuzumab), Nerlynx (chemical name: neratinib), Perjeta (chemical name: pertuzumab), and Tykerb (chemical name: lapatinib).