Association of computed tomography-based body composition with survival in metastatic renal cancer patient received immunotherapy: a multicenter, retrospective study

Objectives: To investigate the association of computed tomography-assessed body composition with survival outcomes of metastatic renal cell carcinoma (mRCC) received immunotherapy.

Methods: In this multicenter, retrospective study, we reviewed 251 mRCC patients who received anti-PD1 from five centers. We analyzed the relationship between BMI, skeletal muscle area (SM), subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and subcutaneous adipose percentage (SAT%) with progression-free survival (PFS) and overall survival (OS). The spatial localization T cells was investigated by multiplex immunofluorescence.

Results: Among 224 evaluable patients, 23 (10.3%) patients were underweight, 118 (52.7%) had normal weight, 65 (29%) were overweight, and 18 patients (8%) were obese. The median age was 55 years and most patients were male (71%). No significant improvement in PFS (HR, 0.61; 95% CI, 0.27-1.42) or OS (HR, 1.09; 95% CI, 0.38-3.13) was observed for the obese patients. Besides, SM, VAT, and SAT were not associated with survival outcomes (all p > 0.05). Interestingly, SAT% independently predicted PFS (as continuous variable, HR: 0.02; 95% CI, 0.01-0.11) and OS (HR:0.05; 95% CI, 0.01-0.39), which remained significant in multivariate modeling (as continuous variable, adjusted HR for PFS, 0.01; 95% CI, 0.00-0.04; adjusted HR for OS, 0.08; 95% CI, 0.01-0.72). These associations were consistent in subgroup analysis of different gender, BMI, PD-L1 positive, and sarcopenia group. Tumor of high SAT% patients had a higher intratumoral PD1⁺ CD8⁺ T cell density and ratio.

Conclusion: High SAT% predicts better outcomes in mRCC patients treated with anti-PD1 and T cell location may account for the better response.

Key points: • CT-based subcutaneous adipose percentage independently predicted progression-free survival and overall survival. • Patients with a higher subcutaneous adipose percentage had a higher intratumoral PD1⁺ CD8⁺ T cell density and ratio.