Cytotoxic T-cell-related gene expression signature predicts improved survival in muscle-invasive urothelial bladder cancer patients after radical cystectomy and adjuvant chemotherapy.

BACKGROUND: Assessment of the immune status of muscle-invasive bladder cancer (MIBC) has previously shown to be prognostically relevant after treatment with curative intent. We conducted this study to develop a clinically applicable immune gene expression assay to predict prognosis and adjuvant chemotherapy benefit. PATIENTS AND METHODS: Gene expression of CD3Z, CD8A and CXCL9, immune cell (IC) populations including stromal tumor infiltrating lymphocytes (sTILs), T-cells, natural killer cells (NK-cells), macrophages, Programmed cell death protein 1 positive (PD-1) IC and tumor subtypes (MD Anderson Cancer Center/MDACC-approach) were assessed in 187 MIBC patients (Comprehensive Cancer Center Erlangen-EMN/CCC-EMN-cohort). A gene expression signature was derived by hierarchical-clustering and validated in The Cancer Genome Atlas (TCGA)-cohort. IC populations in the TCGA cohort were assessed via CIBERSORT. Benefit of platinum-containing adjuvant chemotherapy was assessed in a pooled cohort of 125 patients. Outcome measurements were disease specific survival, disease-free survival and overall survival. RESULTS: The gene expression signature of CXCL9, CD3Z and CD8A correlates with quantitative amounts of specific IC populations and sTILs (CCC-EMN: ρ-range: 0.44-0.74; TCGA: ρ-range: 0.56-0.82) and allows stratification of three different inflammation levels (inflamed high, inflamed low, uninflamed). Highly inflamed tumors are preferentially basal subtype and show favorable 5-year survival rates of 67.3% (HR=0.27; CCC-EMN) and 55% (HR=0.41; TCGA). Uninflamed tumors are predominantly luminal subtypes and show low 5-year survival rates of 28% (CCC-EMN) and 36% (TCGA). Inflamed tumors exhibit higher levels of PD-1 and Programmed cell death 1 ligand 1 (PD-L1). Patients undergoing adjuvant platinum-based chemotherapy with 'inflamed high' tumors showed a favorable 5-year survival rate of 64% (HR=0.27; merged CCC-EMN and TCGA cohort). CONCLUSION: The gene expression signature of CD3Z, CD8A and CXCL9 can assess the immune status of MIBC and stratify the survival of MIBC patients undergoing surgery and adjuvant platinum-based chemotherapy. Furthermore, the assay can identify patients with immunological hot tumors with particular high expression of PD-L1 potentially suitable for immunotherapy.

Risk stratification for locoregional recurrence after radical cystectomy for urothelial carcinoma of the bladder.

PURPOSE: To externally validate the Christodouleas risk model incorporating pathological tumor stage, lymph node (LN) count and soft tissue surgical margin (STSM) and stratifying patients who develop locoregional recurrence (LR) after radical cystectomy (RC) for urothelial carcinoma of the bladder (UCB). In addition, we aimed to generate a new model including established clinicopathological features that were absent in the Christodouleas risk model. METHODS: Prospectively assessed multicenter data from 565 patients undergoing RC for UCB in 2011 qualified for final analysis. For the purpose of external validation, risk group stratification according to Christodouleas was performed. Competing-risk models were calculated to compare the cumulative incidences of LR after RC. RESULTS: After a median follow-up of 25 months (interquartile range 19-29), the LR-rate was 11.5 %. The Christodouleas model showed a predictive accuracy of 83.2 % in our cohort. In multivariable competing-risk analysis, tumor stage ≥pT3 (HR 4.32, p < 0.001), positive STSM (HR 2.93, p = 0.005), lymphovascular invasion (HR 3.41, p < 0.001), the number of removed LNs <10 (HR 2.62, p < 0.001) and the administration of adjuvant chemotherapy (HR 0.40, p = 0.008) independently predicted the LR-rate. The resulting risk groups revealed significant differences in LR-rates after 24 months with 4.8 % for low-risk patients, 14.7 % for intermediate-risk patients and 38.9 % for high-risk patients (p < 0.001 for all), with a predictive accuracy of 85.6 %, respectively. CONCLUSIONS: The Christodouleas risk model has been successfully externally validated in the present prospective series. However, this analysis finds that overall model performance may be improved by incorporating lymphovascular invasion. After external validation of the newly proposed risk model, it may be used to identify patients who benefit from an adjuvant therapy and suit for inclusion in clinical trials.