Aim: In our study, a new grading model (e-GM) including nuclear membrane irregularity highlighted by emerin expression was proposed for renal cell carcinomas (RCC). It was aimed to investigate the relationship of this model with WHO/ISUP grading system, histopathological features, and prognosis.
Methods and results: 86 RCC cases were included in the study. The mean age of the patients was 59.65, and the mean tumor size was 6.36 cm. According to pTNM staging, 45 of the cases were stage 1, 11 were stage 2, 26 were stage 3, and 4 were stage 4. According to e-GM grading, advanced tumor grade was found to be associated with perirenal tissue extension, necrosis, lymphovascular invasion, distant metastasis, advanced pT and TNM stage. Nuclear membrane irregularity caused an increase in tumor grade in 17 wi-GS grade 1 cases, 14 WHO/ISUP grading system (wi-GS) grade 2 cases, and 1 wi-GS grade 3 case. In the stepwise statistical analysis, it was determined that the most important prognostic factor was the TNM stage, followed by age and tumor size.
Conclusions: Statistical analyses showed that nuclear membrane irregularity should be a criterion for classification according to e-GM in wi-grade 2 cases, but not necessarily in wi-grade 1 cases. Nuclear membrane irregularity was a prominent feature at high tumor grades, and its expression in RCCs suggests that it may be a target for tumor-specific treatments.