A total of 5 articles [10, 21, 25, 27, 28] compared TNF-α in two groups of pediatric patients with VMC and 4 [13, 19, 20, 27] compared SOD with significant heterogeneity among studies (TNF-α, I2 = 87.4%, P = 0.001; SOD, I2 = 89.7%, P = 0.001). The gene discussed is SOD1; the disease is liver mesenchymal hamartoma.