Skeletal muscle and visceral adipose radiodensities are pre‐surgical, non‐invasive markers of aggressive kidney cancer

• Published in: Journal of cachexia, sarcopenia and muscle sarcopenia and muscle, 2024-04, Vol.15 (2), p.726-734
• Main Authors: Furberg, Helena, Bradshaw, Patrick T., Knezevic, Andrea, Olsson, Linnea, Petruzella, Stacey, Stein, Emily, Paris, Mike, Scott, Jessica, Akin, Oguz, Hakimi, A. Ari, Russo, Paul, Sanchez, Alejandro, Caan, Bette, Mourtzakis, Marina
• Format: Article
• Language: English
• Subjects: Age; Body composition; Body fat; Body mass index; Clinical outcomes; Grade; Kidney cancer; Lipids; Medical imaging; Medical prognosis; Metastasis; Musculoskeletal system; Overweight; Pathology; Patients; Radiodensity; Sensitivity analysis; Skeletal muscle; Stage; Surgery; Tumors; Variables; Visceral adiposity
• ISSN: 2190-5991; 2190-6009; 2190-6009
• DOI: 10.1002/jcsm.13429

Introduction Most studies on body composition in kidney cancer have been conducted among patients with metastatic disease. Given that aggressive tumours can adversely impact body composition and even non‐metastatic tumours can be aggressive, we evaluated associations between pre‐surgical body composition features and tumour pathological features in patients with non‐metastatic clear cell renal cell cancer (ccRCC). Methods The Resolve Cohort consists of 1239 patients with non‐metastatic ccRCC who underwent nephrectomy at Memorial Sloan Kettering Cancer Center between 2000 and 2020. The cross‐sectional areas and radiodensities of skeletal muscle, visceral adipose, and subcutaneous adipose tissues were determined from pre‐surgical computed tomography (CT) scans at the third lumbar vertebrae using Automatica software. Pearson's correlation coefficients describe inter‐relationships among BMI and body composition variables, while odds ratios (OR) and 95% confidence intervals (CI) estimate associations between continuous body composition features (per 1‐standard deviation) and advanced stage (Stage III vs. Stages I–II) and high Fuhrman grade (Grades 3–4 vs. 1–2) from multivariable logistic regression models that considered the potential impact of biological sex, contrast enhanced CTs, and early age at onset of ccRCC. Results The cohort was predominantly male (69%), white (89%), and had a median age of 58. The proportion of patients presenting with advanced stage and high‐grade disease were 31% and 51%, respectively. In models that adjusted for demographics and all body composition variables simultaneously, decreasing skeletal muscle radiodensity (i.e., more fat infiltration) but increasing visceral adipose tissue radiodensity (i.e., more lipid depletion) were associated with advanced tumour features. Per 8.4 HU decrease in skeletal muscle radiodensity, the odds of presenting with advanced stage was 1.61 (95% CI: 1.34–1.93). Per 7.22 HU increase in visceral adipose tissue radiodensity, the odds of presenting with advanced stage was 1.45 (95% CI: 1.22–1.74). Skeletal muscle index (i.e., sarcopenia) was not associated with either tumour feature. Similar associations were observed for Fuhrman grade, a more direct marker of tumour aggressiveness. Associations did not differ by sex, contrast use, or age at onset of ccRCC. Conclusions Lipid infiltrated skeletal muscle, but lipid depleted visceral adipose tissue were independently associated with advanced tumour features