Classifying Cancer by Genes – Not Organ

Years ago, when I worked in the oncology area in the pharma industry, research oncologists will talk about the future of cancer treatment being based on mutation type – not cancer site. From this morning’s Wall Street Journal (WSJ), “A New Approach to Treating Cancer” that future is near.

Traditionally, cancer type has been based on originating site. If a tumor is found in the lungs, it’s lung cancer. Even if the tumor has traveled elsewhere (metastasized) – to the brain for example, but the original tumor was found on the lungs – we’d still call it lung cancer.

Over the past few years, “targeted therapies” have become mainstream. These cancer treatments aim for specific proteins that are thought to be more abundant in cancer cells, or have become aberrant in cancer cells. Targeted therapies are used often in combination with chemotherapies. Chemotherapies tend to have far-reaching side effects that we are familiar with – nausea, hairloss, prone to infection.

In the near future we may begin to see better genetic typing of a cancer and use the drug that specifically targets that gene. In the referenced WSJ article, a female lung cancer patient was tested for a mutation and the test was positive. Instead of getting chemotherapy first, she received a drug specifically targeting that mutation. Her side effects were so minimal, she couldn’t even “categorize myself like other lung-cancer patients who get chemo.”

Still, we have challenges. We don’t have enough novel drugs targeting most of the genetic mutations we find in a cancer patient. And what WSJ article didn’t mention, but all oncologists can appreciate, is how complex cancer can be, and we aren’t always sure that a cancer is a “one-mutation” problem.