RASSF1A promoter methylation correlates development, progression, and poor cancer-specific survival of renal cell carcinoma: trial sequential analysis

Background: This meta-analysis evaluated the clinicopathologic and prognostic significance of RASSF1A promoter methylation in renal cell carcinoma (RCC). Materials and methods: The ORs or HRs and their 95% CIs were calculated. Trial sequential analysis was conducted. Results: Twenty-two articles that included 1,421 patients with RCC and 724 controls were identified. RASSF1A promoter methylation correlated with RCC in tissue, blood, and urine samples. On multivariate analysis, RASSF1A promoter methylation was associated with tumor grade (grade 3-4 vs 1-2: OR=3.59), clinical stage (stage 3-4 vs 1-2: OR=2.15), T classification (pT2-4 vs pT1: OR=2.66), histologic subtypes (papillary vs clear cell: OR=2.91), and cancer-specific survival (HR=1.78), but it was not linked to age, gender, lymph node status, distant metastasis, or overall survival. The Cancer Genome Atlas data also showed that RASSF1A methylation was significantly more likely to be seen in papillary vs clear-cell RCC (OR=23.19). Conclusion: RASSF1A promoter methylation may be associated with the development and progression of RCC, as well as poor cancer-specific survival. Methylation was more frequent in papillary vs clear-cell RCC. More studies are needed to confirm these findings in blood or urine samples.