To assess whether ASPL-TFE3 RCC, one of the subtypes of Xp11.2 tRCC with a fusion pattern of t(x;17)(p11.2;q25), showed more aggressive progress than other subtypes, we used an ASPL-TFE3 dual-fusion FISH probe for the diagnosis of ASPL-TFE3 RCC. The gene discussed is TFE3; the disease is renal cell carcinoma.