18F-fluorodeoxyglucose positron emission tomography-computed tomography in response assessment of perivascular epithelioid cell tumor of the pelvic cavity to irinotecan and temozolomide

Perivascular epithelioid cell tumors (PEComas) are a rare variety of mesenchymal tumors composed of distinctive cells that show a focal association with blood vessel walls and usually express melanocytic and smooth muscle markers. We present a case of 38-year-old male, diagnosed with PEComa of the pelvic cavity who underwent serial 18F-fluorodeoxyglucose positron emission tomography-computed tomography scans for the assessment of response to the chemotherapeutic combination of irinotecan and temozolomide.