Alveolar soft part sarcoma (ASPS) is a rare tumor of uncertain histogenesis, accounting for only 0.5% to 1% of all soft tissue tumors.[1] The overall 2-year survival rate is 82%, and 5-year survival rate is 56%.[2] ASPS is characterized by der(17)t(X;17)(p11;q25) resulting in ASPSCR1–TFE3 fusion.[3] Demonstration of this particular gene rearrangement is the most desirable diagnostic criterion of ASPS. The gene discussed is TFE3; the disease is neoplasm.