Wednesday, June 8, 2011

Case of the missing mutation

Of the dozens of genetic mutations unique to my melanoma, I’m missing the one I sort of wish I had. I was told by my oncologist this morning that I tested negative for the so-called BRAF V600E mutation, which is found in roughly half of all patients with metastatic melanoma. This mutation causes a protein in melanoma cells to become stuck in the “on” position so that it continuously signals the nucleus to proliferate.

The reason this matters is because a new designer drug has been developed that generates a remarkably potent response in those patients with this particular mutation. In patients without it, the drug can actually accelerate the growth and spread of the cancer. So far the patients who have received vemurafenib have been very sick, some at death’s door. In a majority of cases, the drug shrunk tumors beyond the most optimistic expectations of oncologists. It even caught the attention of The New York Times, which ran a series of articles last summer in which this “Lazarus effect” was documented.

The downside: patients on vemurafenib often stop responding after six or seven months. It may be great science that underlies the product, but it’s not a great medicine. There is no evidence it cures anyone.

I enrolled early last year in a clinical trial at OHSU that granted researchers the right to run genetic tests on melanomas that my surgeon had cut out of me. I could have learned my BRAF status then, but it wasn’t a pressing concern. It isn’t now either, but I have an appointment with my oncologist in three weeks and it makes sense to know whether a new drug is even a therapeutic possibility for me. Other options remain open that hold out the hope for a durable remission, most notably interleukin-2 and Yervoy, about which I’ve written previously.

So while it would be better to have tested positive for the BRAF mutation, I can now focus on other, slightly less desperate strategies. Of the various ways of attacking cancer, there is something intuitively attractive to me about boosting the body’s own immune response to cancer. This is what healthy living and, if necessary, immunotherapy are all about.

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