# Effect of sex-specific abdominal fat tissue composition on WHO/ISUP nuclear grade of clear cell renal cell carcinoma

## TL;DR

This study explores how abdominal fat composition differs between men and women with kidney cancer and relates to cancer severity.

## Contribution

The study identifies sex-specific associations between visceral fat metrics and cancer grade in clear cell renal cell carcinoma.

## Key findings

- Visceral fat area and percentage were significantly higher in high-grade ccRCC patients.
- VF% was a better predictor of high-grade ccRCC in females compared to other metrics.
- Maximal tumor diameter was the strongest predictor in males, while visceral fat percentage was key in females.

## Abstract

To investigate the relationship between sex-related visceral obesity and WHO/ISUP nuclear grade in clear cell renal cell carcinoma (ccRCC).

Between January 2018 and June 2022, 95 patients (56 men and 39 women) with pathologically proven ccRCC who underwent abdominal computed tomography examination were retrospectively examined. The patients were classified into two groups: low- and high-WHO/ISUP nuclear grade ccRCC (n = 58 and n = 37), respectively. Patient height, weight, body mass index (BMI), sex, age, subcutaneous fat area (SFA), visceral fat area (VFA), total fat area (TFA), and percentage of visceral fat (VF%) were recorded for the two groups.

No significant differences were found in age, BMI, SFA, or TFA, but VFA and VF% were significantly higher in the high-grade patient group. In males, maximal tumor diameter (MTD) (67.8% sensitivity and 76.9% specificity) had the highest area under the curve (AUC), while in females, VF% (70.0% sensitivity and 73.7% specificity) had the highest AUC. VF% revealed an odds ratio (OR) of 1.09 in females with high-grade ccRCC, and in males, MTD was an independent predictor of ccRCC with an OR of 1.03.

Sex-related body fat tissue, including VFA and VF%, could be used for estimating WHO/ISUP nuclear grade in patients with ccRCC, especially in females.