PMEL and tuberous sclerosis: In addition to angiomyolipoma, pulmonary LAM cells are also positive for HMB-45 (Venyo, 2016; Guo et al., 2020), indicating that neural crest cells, a kind of migratory, multipotent embryonic cell, maybe the cell origin for LAM and other TSC-related tumors (Delaney et al., 2014).