Table 3.

mTOR-pathway-related molecular alterations association with PEComas

Altered gene	Percent of patients with PEComa with altered genea (%)	Number of patients with PEComa with altered genea	Pathway activated	Drugs with an impact on target
TSC2	32.3	10	mTOR	Sirolimus (rapamycin) Everolimus Temsirolimus
TSC1	9.6	3	mTOR	Sirolimus (rapamycin) Everolimus Temsirolimus
TFE3 fusions	16.1	5	Unclear	None known
FLCN	6.4	2	Unclear	None known

All of the 31 PEComas analyzed for molecular alterations using next-generation sequencing were advanced or metastatic; only one of the tumors was from the skin

Other commonly observed genomic alterations were TP53 (45.2%, 14 patients), RB1 (25.8%, eight patients), CDKN2A (19.3%, six patients), ATRX (9.6%, three patients), CD36 (6.4%, two patients), NF1 (6.4%, two patients), and SMARCB1 (6.4%, two patients)

ATRX alpha-thalassemia/mental retardation, X-linked, CD36 cluster of differentiation (also known as platelet glycoprotein 4), CDKN2A cyclin-dependent kinase inhibitor 2A, FLCN folliculin, mTOR mammalian target of rapamycin, NF1 neurofibromatosis type 1, PEComa perivascular epithelioid cell tumor, TFE3 transcription factor binding to immunoglobulin heavy contrast Mu (IGHM) enhancer 3, RB1 retinoblastoma 1, SMARCB1 SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily B, member 1, TP53 tumor protein 53, TSC1 tuberous sclerosis complex 1, TSC2 tuberous sclerosis complex 2

^aThe alterations in TSC2, TSC1, TFE3, and FLCN all occurred in a mutually exclusive fashion

Republished from [96] with permission from the University of California, Davis Department of Dermatology, Sacramento, California