Humans ; Liver Neoplasms ; pathology ; Perivascular Epithelioid Cell Neoplasms ; pathology

Femoral Neoplasms ; pathology ; Humans ; Perivascular Epithelioid Cell Neoplasms ; pathology

Humans ; Liver Neoplasms ; pathology ; Perivascular Epithelioid Cell Neoplasms ; pathology

Adult ; Epithelioid Cells ; pathology ; Humans ; Male ; Perivascular Epithelioid Cell Neoplasms ; pathology

Child, Preschool ; Epithelioid Cells ; Heart Atria ; pathology ; Heart Neoplasms ; Humans ; Perivascular Epithelioid Cell Neoplasms

Adult ; Cecum ; pathology ; Female ; Humans ; Immunohistochemistry ; Intestinal Neoplasms ; diagnosis ; pathology ; Perivascular Epithelioid Cell Neoplasms ; diagnosis ; pathology

Perivascular epithelioid cell tumors (PEComas) are unusual mesenchymal neoplasms composed of histologically and immunohistochemically distinct perivascular epithelioid cells (PECs). Although PEComas have the potential to behave in a malignant fashion, malignant PEComas arising from the retroperitoneum are extremely rare. A 68-year-old woman presented with a painful palpable mass in her left upper abdomen. Computed tomography of the abdomen showed a 9 cm sized heterogeneous mass in left para-aortic space and multiple hypervascular nodules in the liver. 18F-fludeoxyglucose-PET/CT showed multifocal hypermetabolic lesions in retroperitoneum, liver, and skeletal bones. Percutaneous needle biopsies were done on the retroperitoneal and hepatic mass. Both specimens were positive for human melanoma black-45 (HMB-45) on histological and immunohistochemical staining which was compatible with PEComas. Herein, we report a rare case of retroperitoneal PEComa with multiple metastases involving liver and bone at initial diagnosis that exhibited aggressive behavior and resulted in a devastating prognosis.
Aged ; Bone Neoplasms/pathology/radiography/secondary ; Female ; Fluorodeoxyglucose F18 ; Humans ; Liver Neoplasms/pathology/radiography/secondary ; Perivascular Epithelioid Cell Neoplasms/*diagnosis/pathology ; Positron-Emission Tomography ; Tomography, X-Ray Computed

Cell Proliferation ; Cytoplasm ; metabolism ; Female ; Giant Cells ; pathology ; Humans ; Hysterectomy ; Immunophenotyping ; Middle Aged ; Perivascular Epithelioid Cell Neoplasms ; diagnosis ; Salpingectomy ; Uterine Neoplasms ; diagnosis

Objective: To investigate the clinicopathological features of perivascular epithelioid cell tumor (PEComa) of the lung. Methods: Eight PEComa cases of the lung diagnosed at the First Affiliated Hospital of Soochow University, Suzhou, China from July 2008 to December 2021 were collected and subject to immunohistochemical staining, fluorescence in situ hybridization and next generation sequencing. The relevant literature was reviewed and the clinicopathological features were analyzed. Results: There were 5 males and 3 females, aged from 18 to 70 years (mean 39 years). There were 3 cases of the right upper lung, 3 cases of the left lower lung, 1 case of the left upper lung and 1 case of the right middle lung. Seven cases were solitary and 1 case was multifocal (4 lesions). Seven cases were benign while one was malignant. The tumors were all located in the peripheral part of the lung, with a maximum diameter of 0.2-4.0 cm. Grossly, they were oval and well circumscribed. Microscopically, the tumor cells were oval, short spindle-shaped, arranged in solid nests, acinar or hemangiopericytoma-like patterns, with clear or eosinophilic cytoplasm. The stroma was rich in blood vessels with hyalinization. Coagulated necrosis and high-grade nuclei were seen in the malignant case, and calcification was seen in 2 cases. Immunohistochemically, the tumor cells were positive for Melan A (8/8), HMB45 (7/8), CD34 (6/8), TFE3 (4/7), and SMA (3/8). All cases were negative for CKpan and S-100. TFE3 (Xp11.2) gene fusion was examined using the TFE3 break-apart fluorescence in situ hybridization in 5 cases, in which only the malignant case was positive. The next generation sequencing revealed the SFPQ-TFE3 [t(X;1)(p11.2;p34)] fusion. Follow-up of the patients ranged from 12 to 173 months while one patient was lost to the follow-up. The malignant case had tumor metastasis to the brain 4 years after the operation and then received radiotherapy. Other 6 cases had no recurrence and metastasis, and all the 7 patients survived. Conclusions: Most of the PEComas of the lung are benign. When there are malignant morphological features such as necrosis, high-grade nuclei or SFPQ-TFE3 gene fusion, close follow-up seems necessary.
Male ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Perivascular Epithelioid Cell Neoplasms/pathology* ; Lung/pathology* ; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics* ; Necrosis ; Biomarkers, Tumor/analysis*

Perivascular epithelioid cell tumor (PEComa) is extremely rare, which originated from mesenchymal cells in the intestine, and composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. We report here on a case of PEComa in the sigmoid colon. A 62-year-old woman presented with hematochzia 10 days ago. Her abdominal computed tomography scan showed a 5 cm sized intraluminal fungating heterogeneously enhanced, high density mass, which infiltrated pericolic tissue surrounding the sigmoid colon. Colonoscopy showed a purple colored polypoid mass with lobulating contour in the sigmoid colon. She underwent laparoscopic anterior resection. On the histologic examination, the tumor consisted of polygonal epithelioid cells with sheet-like growth of nests, which looked like alveolar tissues in lung. The tumor cells were strongly positive stained with human melanoma black-45 (HMB-45). Pathologic examination was compatible with PEComa. Sixteen months after surgery, she did well without tumor recurrence after surgery. We review the literatures concerning PEComa of the intestine focusing on endoscopic findings.
Colonic Neoplasms/diagnosis ; Colonoscopy ; Female ; Gastrointestinal Hemorrhage ; Humans ; Melanoma-Specific Antigens/metabolism ; Middle Aged ; Perivascular Epithelioid Cell Neoplasms/*diagnosis/pathology/surgery ; Tomography, X-Ray Computed