Click Image to Enlarge.
Metaplastic breast cancer is a rare and aggressive malignancy that accounts for about 0.2 to less than 5% of all breast cancers. Breast cancer normally starts in the milk-producing glands (lobules), or in the tubes that carry milk to the nipple (ducts). Metaplastic breast cancer also begins in the ducts but is different from other types of breast cancer because the tumor contains multiple cell types. Metaplastic tumors may contain normal breast cancer cells, as well as cells found in other types of cancer, such as malignant squamous cells and sarcoma cells.
Metaplastic breast cancer is usually more aggressive than other types of breast cancer. Metaplastic tumors grow more rapidly and are often much larger at the time of diagnosis. They are also more likely to be advanced (stage III or IV; high-grade) at the time of diagnosis and have a higher risk of recurrence and metastasis. This disease is less likely than normal breast cancer to spread to the lymph nodes, but metaplastic tumors are more likely to spread to distant sites, including the lungs. Metaplastic breast cancer is very often triple-negative, meaning the estrogen, progesterone, and HER-2 receptors are not present in the cancer cells.
A risk factor is anything that increases the possibility of developing a disease. There are no known risk factors specific to metaplastic breast cancer. Please refer to Understanding Breast Cancer - Risk Factors for more information.
There are no symptoms specific to metaplastic breast cancer; however, metaplastic tumors often grow more rapidly and are larger at the time of diagnosis than other breast tumors. Please refer to Understanding Breast Cancer - Symptoms for more information.
Metaplastic breast cancer is diagnosed in the same way as other breast cancers. Please refer to Understanding Breast Cancer - Diagnosis for more information.
Please refer to Understanding Breast Cancer - Staging for more information. Metaplastic breast cancer is staged the same way as other breast cancers.
Metaplastic breast cancer is very often triple-negative, meaning that estrogen, progesterone, and HER-2 receptors are not present in the cancer cells. The targeted therapies and hormone therapies used to treat ductal carcinoma are generally ineffective against triple-negative breast cancers. Thus, metaplastic breast cancer is often treated with the same regimens as triple negative breast cancer. This may include a combination of surgery, chemotherapy and radiation therapy.
Currently, the molecular characteristics of Metaplastic Breast Cancer are being investigated, and new therapies are being developed and tested in clinical trials. These therapies include new chemotherapy regimens as well as targeted therapies that destroy tumor cells by targeting the specific genetic characteristics of the disease. One recent study has shown that metaplastic breast cancers often overexpress programmed death ligand-1, also known as PD-L1. This may mean the tumor is responsive to anti-PD-1 antibody compounds such as Pembrolizumab. Ask your doctor if a clinical trial using novel drugs such as these may be right for you.
Surgical treatment of metaplastic breast cancer can include both breast conserving surgery as well as mastectomy, depending on the number and size of tumors. Studies have shown no significant survival differences between patients with metaplastic cancers who had breast-conserving surgery compared to those who had mastectomies. Ask your doctor which surgical treatment is optimal for your particular case.
Metaplastic breast cancer is known to have a lot of PI3K mutation. The PIK3CA gene gives instructions the body’s cells to make phosphoinositide 3-kinase, a PI3K protein involved in a cell’s life cycle. When the PIK3CA gene is mutated, the instructions it gives are damaged and the PI3K protein does not work properly resulting in the abnormal growing and dividing of cells. Many treatments in clinical trials these days target the PI3KCA gene. You may want to investigate what clinical trials are available.
If you can have a good understanding of your disease and can explain your condition back to your doctor, then you’re in good shape. Questions are your primary resource to gain a better understanding of your disease and enhance your quality of care. Below are some questions you may want to ask your doctor about Metaplastic Breast Cancer:
Copyright © 2025 CMedEd.com
