‘Obesity Paradox’ in Men With Metastatic Melanoma
Posted: Wednesday, April 11, 2018
For patients with metastatic melanoma, obese men may have survival benefits compared with patients with a normal body mass index (BMI), suggest findings from a retrospective multicohort analysis published in The Lancet Oncology. Researchers, led by Jennifer L. McQuade, MD, of The University of Texas MD Anderson Cancer Center, observed these benefits in men treated with targeted or immune therapies—not chemotherapy—but found no “obesity paradox” in terms of survival advantage in women.
“Obese men consistently did much better than men with a normal BMI, with nearly a doubling of overall survival,” said Dr. McQuade in an MD Anderson press release. “The question is what underlying mechanism causes this advantage in obese men, and can we take advantage of it to improve outcomes in patients with melanoma?”
In the six-cohort analysis, the researchers focused on 1,918 patients with metastatic melanoma who had been with treated with targeted therapy (n = 839), immunotherapy (n = 538), or chemotherapy (n = 541). Patients were classified as underweight, normal, overweight, or obese.
In the pooled analysis, obese men had a median progression-free survival of 12.8 months and overall survival of 36.5 months (average adjusted hazard ratio of 0.77). Patients with a normal BMI had a median progression-free survival of 7.2 months and overall survival of 16.0 months. Progression-free and overall survival benefits held true for obese patients compared with normal BMI patients receiving targeted therapy (15.7 months and 33.0 months vs. 9.6 months and 19.8 months, respectively) and immunotherapy (7.6 months and 26.9 months vs. 2.7 months and 14.3 months, respectively).