TFE3 and alveolar soft part sarcoma: A diagnosis of primary ASPS of the lung was rendered on the basis of exclusion of a secondary ASPS and common and not-so-common differential diagnoses of tumors reported in the lung, and on the basis of morphology, IHC (TFE3 positivity), and molecular genetics (TFE3 gene rearrangement) supportive of ASPS.