Obesity has become a well-known risk factor for cancer, and with this in mind, the findings of a new study may come as a surprise; for patients with kidney cancer, being overweight or obese appeared to significantly increase their chances of survival.
Obesity may prolong survival for kidney cancer patients
Senior and corresponding author Dr. Toni K. Choueiri, director of the Lank Center for Genitourinary Oncology at the Dana-Farber Cancer Institute in Boston, MA, and colleagues report their results in theJournal of Clinical Oncology.Numerous studies have shown that individuals with a high body mass index (BMI) are at greater risk for numerous cancers, andkidney cancer is one of them.According to the American Cancer Society, obesity can trigger changes in hormones that lead to renal cell carcinoma (RCC) – the most common form of kidney cancer, accounting for around 9 in 10 of all cases.Being overweight or obese following a cancer diagnosis has also been associated with poorer survival, though some previous studies have indicated that this may not be the case with RCC.
Survival increased by 9 months for overweight kidney cancer patients
This association was validated in an external cohort of 4,657 treated for kidney cancer between 2003-2013, the researchers report.Data from TGCA provided clinical and genomic information on 324 patients with this disease, and another database held information on tissue samples for 146 kidney cancer patients.The team used this information to determine whether there were any molecular differences between kidney cancer patients with a high or low BMI that might explain why the latter has better survival.While TGCA data did not provide any clues, the tissue sample database revealed some variations in gene expression; the researchers found that patients with a high BMI showed reduced expression of a gene called fatty acid synthase (FASN), compared with those with a normal BMI.