Men experience a marked drop in their testosterone levels when taking crizotinib for anaplastic lymphoma kinase (ALK)-positive advanced non–small cell lung cancer (NSCLC), according to a University of Colorado Cancer Center study published in the April issue of Cancer.
Researchers studied the hormone levels in men with ALK-positive advanced NSCLC taking crizotinib after a 35-year-old man taking the drug reported fatigue and sexual disinterest, symptoms that are often related to low testosterone levels.
The study included 38 men with lung cancer. Crizotinib was prescribed to 19 of the study participants, and the other 19 men were receiving other kinds of therapy.
“While testosterone was low in only about 30% of men on other therapies, it was low in 100% of the men who were on crizotinib. And when we started to track it over time, we could clearly see testosterone levels dropping within days of starting on the drug,” said Andrew Weickhardt, MD, senior clinical fellow at the CU Cancer Center, and one of the study’s co-authors.
The effects of low testosterone could be profound, since men may stay on crizotinib for months or even years.
“Low testosterone can reduce bone density and muscle strength as well decrease sex drive and increase fatigue and depression. There are many factors associated with a cancer diagnosis that can lower testosterone, but the levels in crizotinib-treated patients were so uniformly low and their direct relationship with starting the therapy meant there was no doubt the drug was contributing to it, ” said endocrinologist Micol Rothman, MD, co-author of the study. “Fortunately, we can easily test for and treat this condition.”
“Testing hormone levels and providing testosterone supplements is a simple way to improve the way these men feel,” said Weickhardt. “It’s not just about sex drive, it’s about overall quality of life.”
Source: University of Colorado Cancer Center.