Malignant perivascular epithelioid cell tumor of the uterus with lung metastasis.

Perivascular epithelioid cell tumor (PEComa) is an extremely rare mesenchymal tumor, which can arise in a wide array of anatomic locations, and is characterized by its myelomelanocytic phenotype and unpredictable natural history. Specifically, PEComas, which occur in non­classic anatomic distributions, are known as PEComa–not otherwise specified (PEComa‐NOS) [1]. To the best of our knowledge, a total of 234 cases of PEComas­NOS have been reported in English published reports. Of those, 47 were uterine PEComas cases, which included 31 tumors of benign behavior and 16 tumors of locally aggressive behavior with distant metastasis to liver, lungs, intestines, bone, and lymph nodes. Here, we report a very rare malignant uterine PEComa with lung metastasis in a 49­year­old unmarried woman, despite adjuvant chemotherapy after initial surgery.