Perivascular epithelioid cell tumors (PEComas) are rare and are characterized by the expression of myomelanocytic markers. They are a complex family that includes angiomyolipomas, lymphangioleiomyomatoses and other soft tissue and visceral tumors. Due to the low prevalence of these tumors, the natural history is unclear; furthermore, a molecular classification integrating clinical, pathological and molecular parameters has not been described to date.

Inclusion criteria:

• Major patient (≥18 years)
• Minor patient (1 to 17 years old)
• PEComas diagnosed in France between 01/01/1990 and 15/09/2019 and reviewed by a sarcoma referral pathologist

Exclusion criteria :

• Opposition of the patient (or the holders of parental authority) to participate in the study
• Biological tissue from a patient who does not meet all the inclusion criteria
• Classic triphasic angiomyolipoma or lymphangioleiomyomatosis
• Inability to provide informed information to the subject
• Patient under court protection
• Patient under guardianship or curatorship

patients having PEComas diagnosed in France between 01/01/1990 and 15/09/2019 and reviewed by a sarcoma referral pathologist