Author Interviews, Lancet, Melanoma, Weight Research / 14.02.2018
Another Obesity Paradox: Obese Males Have Survival Advantage in Melanoma
MedicalResearch.com Interview with:
Jennifer McQuade, M.D., lead author
Melanoma Medical Oncology
The University of Texas MD Anderson Cancer Center
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Melanoma is the most deadly of the common skin cancers, and for many years we lacked effective therapies for patients with disease that had spread (metastatic). Over the past 7 years, there has been FDA approval of 2 new classes of drugs that have dramatically improved the survival of patients with metastatic melanoma. Checkpoint inhibitor immunotherapies “take the brakes” off patients’ immune system to allow the immune system to eliminate the cancer. Targeted therapies turn off key molecules expressed by some tumors (BRAF mutant) that they rely on for sustained growth and division.
While these types of therapies can result in dramatic long-term disease control in some patients, others may not have any shrinkage of their tumors. Some differences may lie in the tumors themselves, but there is also increasing evidence that “host” factors such as the microbiome and lifestyle choices might influence outcomes in cancer patients.
Obesity has been associated with an increased risk of many cancers, and is in fact poised to overtake smoking as the leading preventable cause of cancer. One of the ways that obesity may increase tumor growth is by increasing levels of insulin and other growth factors which then activate a pathway called the PI3K pathway that leads to continued tumor growth. As that PI3K pathway has also been shown to cause resistance to targeted and immune therapies in melanoma, we hypothesized that obesity would be associated with worse outcomes in patients with metastatic melanoma treated with these therapies.
(more…)