Increased body mass index (BMI) and its related metabolic syndrome, often associated with systemic inflammatory states and altered tumor biology in various cancers. Given the potential for BMI to serve as a readily accessible marker of chronic inflammation and its possible influence on tumor immune evasion, this study aims to explore the relationship between BMI and PD-L1 expression in renal cell carcinoma (RCC)

This is a cross-sectional study, utilizing retrospective data from the medical records of patients diagnosed with RCC at Hasan Sadikin Hospital, a tertiary referral center. Immunohistochemical (IHC) staining for PD-L1 was performed on formalin-fixed, paraffin-embedded tumor tissue sections. A board-certified pathologist, blinded to the BMI measurements assessed and categorized PD-L1 expression. The expression was categorized as: Negative (no expression), +1 (weak expression),+2 (moderate expression), +3 (strong expression). A spearman corelation was used to analyse the corelation between IMT and PDL-1 expression.

A total of 15 patients met the study's inclusion criteria, comprising 9 males and 6 females. The mean age of the cohort was 53.7 years (SD 12.9). Ten patients (66.7%) reported a history of smoking. The histological subtypes of renal cell carcinoma were as follows: clear cell (n=10, 66.7%), papillary (n=4, 26.7%), and sarcomatoid (n=1, 6.7%). A strong positive and statistically significant correlation (r = +0.767) was observed between BMI and PD-L1 expression in renal cell carcinoma.

We observed a strong, positive, and statistically significant correlation between body mass index (BMI) and PD-L1 expression within the RCC tissue. This finding suggests that increased BMI, a potential indicator of chronic systemic inflammation, may be associated with elevated PD-L1 expression in RCC