High BMI, Visceral Obesity May Benefit Kidney Cancer Patients
MILAN—Patients being treated for renal cell carcinoma (RCC) may have better outcomes if they have a high body mass index (BMI) or a large amount of visceral fat, according to separate studies presented at the 28th annual congress of the European Association of Urology.
In one study, German researchers reported that a high BMI at the start of systemic palliative treatment for advanced or metastatic RCC is associated with better overall survival compared with low or normal BMI. In a prospective study of 475 patients who received first-line systemic treatment for advanced or metastatic RCC, Peter-Jurgen Goebell, MD, of Friedrich Alexander University in Erlangen, Germany, and colleagues found that the median overall survival was 23.4 months among patients with a BMI above 28 kg/m2 compared with 10.0 and 16.7 months for those with a BMI less than 24 and 24-28, respectively. The researchers noted that the underlying mechanism by which high BMI is associated with longer survival is unclear.
In the other study, by Gou Kaneko, MD, and collaborators at Keio University School of Medicine in Tokyo found that a high visceral fat area (VFA) as measured with preoperative computed tomography was associated with a decreased risk of cancer recurrence after surgery for localized clear-cell RCC. The study included 241 patients, of whom 151 underwent radical nephrectomy and 90 underwent partial nephrectomy. After a median follow-up of 35.6 months, 28 patients (11.6%) experienced recurrence.
The five-year recurrence-free survival rate was 88.7% in patients with a high VFA (120 cm2 or above) versus 71% among patients with a low VFA (less than 120 cm2), a significant difference between the groups. Compared with a high VFA, a low VFA was associated with a significant twofold increased risk of recurrence. High BMI did not predict independently predict recurrence.
Visercal fat is thought to be the largest endocrine organ, the authors pointed out, and it produces several hormones and cytokines related to carcinogenesis and tumor progression.