Mesothelioma is an especially deadly kind of lung cancer, with a five-year survival rate of only 12% (American Cancer Society figures). The major risk factor for mesothelioma is asbestos exposure. Exposure could be from work, or household (asbestos insulation, for example), or even environmental. For example, serpentine, the state rock of California, contains asbestos, and dust from serpentine rocks can be a risk factor, so California has programs to reduce exposure to naturally occurring asbestos.
Until now, treatments for mesothelioma have not improved outcomes greatly. But very promising results have just been reported in JAMA Oncology from a clinical trial, combining a new drug with the standard chemotherapy. The proportion of patients who survived to 36 months was 4 times greater than those who got chemotherapy without the new drug. This is a huge improvement! Moreover, the new drug was not associated with any significant side effects.
The idea behind this drug is that researchers learned that mesothelioma tumor cells cannot make arginine, an amino acid that normal body cells can make. The tumor cells have to absorb it from arginine-containing foods like fish, meat, dairy, and beans. The new drug blocks arginine from being absorbed, which doesn’t hurt the rest of the body because those cells can make their own arginine.
A historic note: a number of companies that made asbestos-containing products have gone bankrupt, leaving affected workers without compensation. I’ll leave it to legal experts to describe efforts to remedy this through legislation and trust funds.