NEW YORK—Obese patients with kidney tumors have 48-percent higher odds of developing a clear-cell renal cell cancer (RCC) than patients with a body mass index (BMI) of less than 30; odds increase by 4 percent for every extra BMI point, according to a new study published in the January issue of the journal BJU International.
Researchers at the Memorial Sloan-Kettering Cancer Center studied 1,640 patients with kidney tumors and found 88 percent had malignant tumors and 61 percent of these were clear-cell RCCs. The remaining 12 percent had benign tumors. When they factored in the patient's weight, they discovered that there was a significant association between obesity and clear-cell RCC, which accounts for up to 80 percent of RCC cases and is one of the more lethal variants.
“Recent scientific breakthroughs about what causes clear-cell RCC have led to the development of new targeted therapies" said lead author Dr. William T. Lowrance. "This makes it more important than ever to identify those people who face an increased risk of developing this variant, which is on the rise in the United States. A number of studies have suggested that obesity could be a risk factor for RCC, but the exact reason is unknown. Researchers suggest it might be secondary to hormonal changes, decreased immune function, hypertension or diabetes in obese patients."