1.Clinicopathological analysis of two cases of malignant perivascular epithelioid cell tumor in the retroperitoneum and pelvic cavity and literature review
Lihao CHEN ; Kaifeng LIU ; Gaozhen HUANG ; Quanqing TANG ; Shihao LI ; Zhijian XU ; Hongwei LIU
Journal of Modern Urology 2024;29(5):445-449
【Objective】 To investigate the clinicopathological features and key points of diagnosis and treatment of malignant perivascular epithelioid cell tumor (PEComa) to increase awareness of the disease. 【Methods】 The clinicopathological data of 2 patients with malignant PEComa treated in our hospital were retrospectively analyzed, and relevant literatures were reviewed. 【Results】 Both patients were male, aged 53 and 16 years, respectively.The sites of occurrence were in the retroperitoneum and pelvis, respectively.Both tumors were resected surgically, and the diagnosis was confirmed with postoperative pathology.Under the microscope, the tumor tissue of one patient was mainly composed of smooth muscle-like cells, and that of the other patient was composed of epithelioid cells, both showing pathological mitotic images and expressing HMB45, Melan-A, SMA and CD34, no tumor recurrence or metastasis was observed during the follow-up.The literatures collected involved 15 patients with retroperitoneal or pelvic PEComa, including 3 males and 12 females, of which 9 were malignant.The clinical manifestations were abdominal pain, bloating, or lower back pain.Some cases were detected during physical examinations. 【Conclusion】 Malignant PEComa is difficult to be diagnosed before surgery and easy to be misdiagnosed.The confirmed diagnosis depends on the postoperative pathological results.The preferred treatment is complete resection of tumor.Long-term follow-up is needed.