External validation of a four-tiered grading system for chromophobe renal cell carcinoma

This study aimed to validate the prognostic value of a four-tiered grading system recently proposed by Avulova et al. and to explore the prognostic ability of another four-tiered classification grading system in which there is a separate Grade 3 for tumor necrosis. Grading of chromophobe renal cell carcinoma (ChRCC) by the Fuhrman system is not feasible because of the inherent nuclear atypia in ChRCC. We collected relevant data of 263 patients with ChRCC who had undergone surgery in our hospital from 2008 to 2020. The Kaplan –Meier method was used to calculate the survival rate and Cox proportional hazard regression models to assess associations with cancer-specific survival and distant metastasis-free survival by hazard ratios (HRs) and 95% confidence intervals (CIs). Ten patients died from ChRCC, and 12 developed me tastases. The 5 year CSS rates were 95.9%. Grades 2 (HR = 10.9; CI 1.11–106.4;P = 0.04), 3 (HR = 33.6, CI 3.32–339.1;P = 0.003), and 4 (HR = 417.4, CI 35.0–4976.2;P <  0.001) in a four-tiered grading system were significantly associated with CSS in a multivariate setting. However, the difference in CSS between Grades 2 and 3 was not significant (HR = 2.14, 95% CI 0.43–10.63;P = 0.35). The HRs of the associations between an exploratory grading system that includes a separate Grade 3 for tumor necrosis and CSS were as follows: Grade 2, 10.2 (CI 1.06–97.9,P = 0.045); Grade 3, 11.4 (CI 1.18–109.6,P = 0.04); a...
Source: Clinical and Experimental Medicine - Category: Research Source Type: research