In 2005—TNBC had not even been named yet.
By 2010—several hundred publications in that year alone.
• About a third of breast cancer deaths come from TNBC.
• Claudin low breast cancer, a new subtype, is also likely to be TNBC.
• Inherited breast cancer—BRCA1 and BRCA2—women with these have 50-80 percent risk of breast cancer over their lives. Recommend mastectomy and removal of ovaries for these women. If women with BRCA1 mutations gets cancer, 80 percent of time it is TNBC. This is called BRCA-associated breast cancer. Why is there such close associations? If a woman without mutation gets TNBC, what does this tell us? We don’t know yet.
• No PARP inhibitors approved yet. Interesting study in BRCA-associated cancers. Women given just a PARP inhibitor—without chemo---and the tumor shrunk. Drugs in early development, may be a positive way forward for those with inherited mutations.
• What about women without inherited mutations? (Sporatic cancers.) A study on women with metastatic TNBC who were given iniparib, a PARP inhibitor, which was added to the therapy; it controlled cancers longer; women lived longer. Not replicated in a larger study, however. Disappointing result.
• Clinical trials are essential—consider enrolling.
Relapse to the brain. Reseachers pay attention to brain metastases because the brain acts differently—it responds to surgery. Most common type to move to brain is Her2-positive. Second is TNBC. With Her2, can move only to brain. TNBC tends to come back in the brain as well as other places at the same time; it may have to be treated differently than Her2-positive cancer. Brain metastases research is a very active field. In the past, there had been a tendency to lump brain metastases together—breast, melanoma, lung. Now, break into different types of cancer and different types of breast cancer. The blood-brain barrier needs to be considered. Research now specifically on PARP inhibitors for TNBC that has metastasized to the brain. There have been advances in standard therapy, such as surgery, for brain metastases.
What can do to reduce risk, especially without risk factors. Most of the time, we do not know why one woman gets breast cancer and another one doesn’t. There’s the risk of getting the cancer—research is ongoing on how to peg individual risk. Separate from that is how to reduce the risk of an already-formed cancer from coming back. Know how to prevent from recurring—surgery, chemo, radiation. Beyond that, everything is an investigation. There is reason to think a healthy lifestlye helps across the board. Simply do not know how it affects the risk of relapse.
Are treatments different for women with BRCA mutations and those without? No, at this point both would be treated the same.
CMF: One of our earliest drug regimens that has been effective but is being replaced by more modern regimens. Still being used for women who cannot tolerate newer ones. One study showed that CMF actually better than AC chemo. Not a significant benefit, but would not avoid CMF.
Follow-up Testing: What is the best method in following after treatment? ASCO Guidelines—physical and careful history every three to six months for the first three years; every six to 12 months in years four and five. Breast imaging, usually mammography, but sometimes MRI every year. In most cases, no bone scans or CAT scans, or blood work.
Metaplastic breast cancer as is relates to TNBC. Metaplastic are relatively unusual. (As few as 1 percent of all cases.) It is a specific subtype. Most breast cancers are either ductal or lobular. Others are pathologically different. Metaplastic has a funny appearance. Unusual. Almost always TNBC. Don’t know if there is a specific treatment difference. Acts like other breast cancers. May have more of the claudin low subtype.
If you have cancer in one breast, should you have the other breast removed? Prophylactic mastectomy in general is limited to those with an inherited risk. If have risk factors and are having mastectomy, it makes some sense to remove both breasts at the same time. For women who have sporatic TNBC, the decision between lumpectomy and mastectomy is a personal one. The decision there is not different for women with TNBC as opposed to others.