Progress for triple-negative breast cancer

Sandy had triple-negative breast cancer. Triple-negative is a phenotype that doesn't tell you all that much; it's defined by what it isn't, as opposed to what it is. Triple-negative simply means that the tumor cells are not estrogen-receptor-positive (ER+), progesterone-receptor-positive (PR+), or Her2-amplified (Her2+). So you can't use any of the targeted therapies for it — none of the hormonal agents or Herceptin; broad-spectrum chemo has been just about it. TNBC is so heterogeneous that it's been difficult to discuss it, let alone find effective treatment. 

Now, an ambitious and apparently hard-working group of researchers have identified six TNBC subtypes, and the information is pretty exciting. For each subtype, there are different types of genes that are enriched or overactive. Using this data, researchers should be able to identify targets and then develop targeted therapies. This is great news for every woman who has been diagnosed with TNBC, which is typically more aggressive and more likely to occur in younger women and in African-American women. TNBC kills women faster than the other phenotypes, and anything we can do to curb it will be cause for celebration along the way to the ultimate victory of a cure.

Snoqualmie Falls, December 2006, during her initial chemo.
Targeted therapies should bring less-toxic treatments for
all stages of cancer. Less fatigue, less nausea,
less damage to vital organs - all good.

One of the most exciting findings is that one of the TNBC subtypes overexpresses androgen receptors. Many prostate cancers are androgen-receptor-positive (AR+), and there are already FDA-approved drugs on the market that work against these cancers. If we can develop an effective way to identify which triple-negative breast cancers are AR+, we may have a new treatment available for them very soon. It's not a cure, but if it can reduce recurrence from primary tumors or slow growth in metastatic cancer, it'll be a godsend for those patients.

I learned about this through a webinar for Project LEAD graduates, and again, I'm impressed with the National Breast Cancer Coalition. A prominent breast cancer research scientist walked us through the research and its implications, giving me a much greater understanding than I had simply from reading the paper. Of course, as I listened, I couldn't help trying to identify Sandy's TNBC subtype based on the types of genes enriched in each of the subtypes and what we knew about Sandy's original tumor. Her cancer was most likely Basal-like 2, a subtype that is particularly aggressive, and definitely not the kind that has androgen receptors.

We need progress for all kinds of breast cancer. I know women with metastatic ER+ cancer, and they'll tell you that there is no such thing as a "good" breast cancer. Lives are at stake. I look forward to more cause to celebrate. And, of course, still in my denial, I hope for a retroactive cure.