First description of primary perivascular epithelioid cell tumour (PEComa) of the prostate: a case report and literature review.

==inizio abstract==

We report an interesting case of primary epithelioid cell tumor (PEComa) of the prostate in a 79 year-old man with non neurogenic male lower urinary tract symptoms secondary to prostatic obstruction. This patient was underwent to surgical intervention of transurethral resection of the prostate ( TURP) because not responsive to drug treatment. Histological and immunohistochemical findings were consistent with perivascular epithelioid cell tumour.
Perivascular epithelioid cell tumors, better known as PECOMAs, are mesenchymal tumors containing variable component of smooth muscles, fat and vessels. PECOMAs are a very uncommon pathological finding. Perivascular epithelioid cell tumors are defined by the WHO as unusual mesenchymal tumors which present histologically and immunohistochemically distinctive perivascular epithelioid cells. In English medical literature it has rarely been reported, PEC-derived tumors have been documented in various anatomical locations, including the uterus, skin, liver/falciform ligament, upper aero-digestive, bone, pancreas, colon et al. The uterus is the predominant site. In the genitourinary system, mostly urinary bladder, PEComas of the prostate are rare. This is the second report of a case definitively diagnosed as PEComa in the prostate. The serum levels of prostate-specific antigen was within normal limits, 2,3 ng/ml. Histological features showed aggressive behaviour, and the patient after oncology consulting was underwent to radiation treatment. Follow up until december 2013 by cystoscopy and CT of the chest/abdomen/pelvis with intravenous contrast showed a disease-free survival. PEComas have been described in different organs and are considered ubiquitous tumors. PECOMAs are malignant tumours and prostate PECOMAs are no exception; their clinical behaviour varies widely from complete remission to local, distal metastasis and even death, despite there are a few cases in the literature and therefore the best method of treatment has not been codified, it is recommended to take an aggressive clinical behavior in the treatment of this neoplasm.

==fine abstract==