Immune-imaging biomarkers: Prognostic value of splenic volume and circulating lymphocytes in upper tract urothelial carcinoma.

Splenomegaly has been linked to a poor prognosis in certain cancer types, possibly due to a weakened immune system. The present study evaluated the association between splenic volume (SV) and oncological outcomes in patients with upper tract urothelial carcinoma (UTUC) after radical nephroureterectomy (RNU). A total of 465 patients with non-metastatic UTUC who underwent RNU between 2009 and 2020, with available preoperative abdominal computed tomography scans and hemogram data collected within 1 month before the operation, were retrospectively analyzed. SV (cm3) was calculated using the cross-sectional area summation method and standardized by body surface area (m2). A receiver operating characteristic curve identified 79 cm3/m2 as the optimal SV cut-off. Patients were stratified by SV and lymphocyte percentage (lym%) values. Survival outcomes were evaluated using Kaplan-Meier analysis and multivariate Cox regression analysis. Among the 465 patients, those with high SV (n=206; 44.3%) demonstrated significantly shorter overall survival (OS) and cancer-specific survival (CSS) times. Stratified analysis showed that patients with both elevated SV and low lym% had the poorest outcomes, including significantly shorter metastasis-free survival (MFS) time. Multivariate analysis confirmed that the combined high SV/low lym% phenotype was an independent predictor of OS, CSS and MFS. In conclusion, the combination of high standardized SV and low lym% was independently associated with an unfavorable prognosis following RNU in UTUC. This dual biomarker approach may enhance risk stratification and inform tailored postoperative management.