Q. What if chemo doesn’t work?
A. You’ll most likely find that out sooner rather than later. Women with a triple negative diagnosis are more likely to suffer a recurrence within the first three years than women with hormone-receptive or HER2-neu-positive cancer. In fact, the recurrence rate for TNBC is about 32% in the first 5 years, compared to around 15% for women with other breast cancers. If you can get through those first 5 years after treatment cancer-free, then your chances are excellent that you’ve beat it.
Q. And if the cancer comes back…?
A. There are other treatments on the horizon, some closer to becoming reality than others.
The use of the drug Avastin in conjunction with chemo has had good results in clinical trials, and has actually been approved by the FDA for use in advanced breast cancer. Avastin, a co-called antiangiogenic drug, keeps tumors from growing the blood vessels they need to ensure a steady blood supply.
One of the most popular diabetic drugs in the U.S., metformin (a.k.a. Glucophage, Fortamet, et. al.), has had extremely positive results against all types of breast cancer, including triple negative, when given at low levels with chemo drug Adriamycin. While still in Phase III clinical trials, the combination of these two drugs both eliminated tumors, and prevented their regrowth; while Adriamycin alone simply kept the tumors from growing, without fully eliminating them.
Another promising treatment is a class of drugs called PARP inhibitors. PARP1 is a gene involved in helping cells recover from the natural damage they incur as they grow. If this gene is inhibited – prevented from doing its job – cancer cells are unable to repair themselves, and they die.
A possible future treatment, currently in phase II clinical trials, is the drug Tarceva®, an EGFR inhibitor. EGFR (epidermal growth factor receptor) helps cells grow and proliferate; when it’s “inhibited” (disabled), cancer cells can’t grow.
Finally, a phase II trial using bisphosphonates – the drugs commonly used to treat osteoporosis – to inhibit the spread of TNBC to the bones has shown promising results.
Q. I still feel like I drew the short straw here…
A. A diagnosis of triple negative breast cancer, with its lack of multiple treatment options, may seem devastating at first. But researchers are making huge strides in discovering new ways, beyond hormone therapy and Herceptin, to stop the spread of all breast cancers.
And treatment for triple negative cancers are definitely getting front-burner treatment. As oncologist Mark Pegram, M.D., of the Sylvester Comprehensive Cancer Center in Miami notes, once researchers discover what TNBC is, rather than what it isn’t, “We’ll stop calling it triple-negative and start calling it something positive.” Just as Herceptin was developed to treat HER2-neu cancers – once their “Achilles heel” was identified – the same will be true for TNBC.