The pooled results showed that RCC patients with KRAS mutation has no significant different OS compared with patients with KRAS wild type (HR = 0.77, 95%CI = 0.58–1.02, p = 0.073; I2 = 62.1%), see Fig. 4; however, LCC patients with KRAS mutation has a shorter OS than patients with KRAS wild type (HR = 1.21, 95%CI = 1.08–1.36, p < 0.01; I2 = 29.0%), see Fig. 5. The gene discussed is KRAS; the disease is leukoencephalopathy with calcifications and cysts.