Quantitative assessment of perirenal fat density in renal cell carcinoma: a combined radiologist-driven and YOLO-based CT study

This is the authors' abstract. We don't add key points for this paper.

Aim To compare perirenal adipose tissue density (PRFD) between patients with renal cell carcinoma (RCC) and healthy controls using non-enhanced computed tomography, and to compare manual measurements and YOLOv8-based machine learning (ML) of PRFD. Materials and methods The study involved 57 patients with confirmed RCC and 82 control subjects. PRFD was measured manually at different levels of the kidneys and other tumor features. The ML analysis utilized specific attenuation intervals to evaluate PRFD and assess agreement with manual measurements. Results RCC group had significantly lower PRFD values at the upper renal pole compared to controls (right: p = 0.040; left: p = 0.032), while other kidney sections showed no significant differences. In healthy controls, there was a significant right-left difference at all levels, whereas in RCC patients this was seen only at the upper pole ( p = 0.005). Tumor size was positively correlated with PRFD in specific regions. Tumor volume categories were significantly associated with the presence of tumoral necrosis ( p = 0.003). The ML method generally aligned with manual measurements, but accuracy varied based on the normalization technique used. Conclusion The study found that PRFD varies between RCC patients and controls, particularly at the upper pole, relating more closely to tumor size than to sex or histological type. As the groups were not age-matched, this difference may partly reflect age rather than disease status. The findings suggest that PRFD could be an important imaging marker for RCC evaluation.