Cancer immunotherapy may have a dark side – Science Magazine

Summary

A growing number of fast-progressing cancer cases point to a dark side for so-called checkpoint inhibitors, a type of immune-stimulating drug that has had near-miraculous results in some people with advanced cancer. Only about 20% of patients respond long-term to the drugs, and oncologists are warning that in a few, they may stoke tumor growth. Despite accumulating papers and anecdotal reports of such tumor “hyperprogression,” some cancer researchers wonder whether it is simply an illusion—whether the patients’ tumors were destined to grow rapidly even before checkpoint inhibitor treatment. Next week in Atlanta at the annual meeting of the American Association for Cancer Research, researchers will try to resolve how to pin down whether hyperprogression is real and, if so, how to identify which patients should not receive these increasingly popular drugs.