Large Retroperitoneal Perivascular Epithelioid Cell Neoplasm (PEComa): A Case Report and a Brief Review

Objective: To describe a case of retroperitoneal perivascular epithelioid cell tumor (PEComa) and to discuss the main features of this rare pathology. Introduction: PEComas represent a rare cluster of neoplasms with uncertain origin; their precursor cells are spindle-shaped and characterized by a myomelanocytic phenotype, so only immunohistochemical staining makes a definitive diagnosis possible. To date, less than three hundred cases are reported in Literature and retroperitoneal site accounts for 7-8% of overall locations. Case Report: Middle-aged female has visited for abdominal pain and urinary complaints; physical findings and imaging demonstrated a huge inhomogeneous mass occupying right abdomen and arising from renal capsule. After multidisciplinary evaluation, patient has been addressed to open surgery and an en-bloc resection of the mass, with right nephrectomy and adrenalectomy. Immunohistochemical staining made a diagnosis of PEComa possible. After an uneventful postoperative stay, the patient entered a follow up protocol, without signs of local recurrence and distant metastases. Conclusion: Retroperitoneal PEComa often presents as a bulky mass with renal and adrenal involvement. Surgical resection should be aimed to obtain a complete removal with negative margins; this makes compartment surgery and en-bloc resection mandatory. Immunostaining is the key methods for a correct diagnosis.