TSC1 and TSC2 mutations also occur in sporadic RCC, including CCRCC, ChRCC, unclassified eosinophilic RCC, RCCLMS, eosinophilic solid and cystic renal cell carcinoma (ESC-RCC), hybrid oncocytic/chromophobe tumour (HOCT) and chromophobe-like RCC, low-grade oncocytic tumour (LOT) of the kidney, and eosinophilic vacuolated tumour (EVT), though at a low frequency [11]. The gene discussed is TSC1; the disease is nonpapillary renal cell carcinoma.