Perivascular epithelioid cell tumors (PEComas) refers to a family of mesenchymal neoplasms composed of angiomyolipomas, clear cell “sugar” tumors of the lung, and lymphangioleiomyomatoses. These tumors have a distinctive and common component of perivascular epithelioid cells that show an association with blood vessel walls and immunohistochemically display myomelanocytic differentiation. The unique neoplasms have been shown to have an expanded range through a variety of case reports, including visceral, intra-abdominal, soft tissue, and bone tumors. The retroperitoneum, abdominopelvic region, and uterus have been reported to be the most common sites. Most PEComas follow a benign course. However, reports of malignant PEComas are increasing. Many papers have described uterine PEComas, but to our knowledge, there have not yet been any reports of a malignant PEComa arising concomitant with another epithelial tumor and mesenchymal tumor. We report herein the case of a 67-year-old woman who experienced a malignant uterine PEComa infiltrating a preexisting intramural leiomyoma with synchronous well differentiated endometrial carcinoma and multiple liver and lung metastases.
Aged ; Angiomyolipoma ; Blood Vessels ; Endometrial Neoplasms* ; Epithelioid Cells ; Female ; Humans ; Leiomyoma* ; Liver ; Lung ; Lymphangioleiomyomatosis ; Neoplasm Metastasis ; Perivascular Epithelioid Cell Neoplasms* ; Uterus*

Perivascular epithelioid cell tumor (PEComa) is a rare family of related mesenchymal neoplasms that include angiomyolipoma, lymphangiomyomatosis and clear cell 'sugar' tumor of the lung. Although this type of tumor has been described in the literature in organs such as kidney, lung, uterus and urinary bladder, there are few reports of gastrointestinal tract-related tumor. We report here on a case of PEComa arising in the transverse colon. This occurred in a 41-year-old male who had no history of tuberous sclerosis complex. Histopathologically, the tumor consisted of nests or sheets of epithelioid cells with eosinophilic cytoplasm. The tumor cells were positive for HMB-45, vimentin and caldesmon, but they were negative for S-100 protein, cytokeratin and CD117, according to immunohistochemical staining. Careful follow up is warranted because the biological behavior of PEComa has not yet been documented. We present here a case of colonic PEComa that was confirmed by immunohistochemical staining and the histopathologic findings, and we include a review of the literature.
Adult ; Angiomyolipoma ; Calmodulin-Binding Proteins ; Colon* ; Colon, Transverse ; Cytoplasm ; Eosinophils ; Epithelioid Cells* ; Humans ; Keratins ; Kidney ; Lung ; Lymphangioleiomyomatosis ; Male ; Perivascular Epithelioid Cell Neoplasms ; S100 Proteins ; Tuberous Sclerosis ; Urinary Bladder ; Uterus ; Vimentin

No abstract available.
Orbit* ; Perivascular Epithelioid Cell Neoplasms*

Actins ; metabolism ; Angiomyolipoma ; pathology ; Carcinoma, Renal Cell ; pathology ; Diagnosis, Differential ; Epithelioid Cells ; metabolism ; pathology ; Female ; Gastrointestinal Neoplasms ; pathology ; Gastrointestinal Stromal Tumors ; pathology ; Humans ; Kidney Neoplasms ; metabolism ; pathology ; Lung Neoplasms ; pathology ; Lymphangioleiomyomatosis ; pathology ; Male ; Melanoma ; pathology ; Melanoma-Specific Antigens ; metabolism ; Pancreatic Neoplasms ; pathology ; Perivascular Epithelioid Cell Neoplasms ; metabolism ; pathology ; Sarcoma, Clear Cell ; pathology ; Skin Neoplasms ; pathology ; Uterine Neoplasms ; pathology

Perivascular epithelioid cell tumors (PEComas) at the uterus are very rare tumors and about 30 cases have been reported as far as we know. As a case was experienced at our hospital, we would like to report it with a brief review of literature.
Epithelioid Cells* ; Perivascular Epithelioid Cell Neoplasms ; Uterus*

Heavily pigmented perivascular epithelioid cell tumors (PEComa) are rare, only eight cases of which have been reported. Unlike typical epithelioid angiomyolipoma, most of these tumors have been encountered in female patients without tuberous sclerosis. The long-term prognosis thereof is undetermined. Cytological similarity and heavy melanin pigment make it difficult for pigmented PEComa to be differentiated from pigmented clear cell renal cell carcinoma or malignant melanoma. The immunoprofile of tumor cells, such as human melanoma black-45 expression, as well as the absence or presence of other melanocytic or epithelial markers, are helpful in determining a differential diagnosis. Here we report a case of heavily pigmented PEComa of the right kidney and review the literature describing this tumor. In this case, the immunoprofile and clinical features corresponded well to those described in the literature. Since the prognosis of such disease has not yet been established, close follow-up of this patient was recommended.
Angiomyolipoma ; Carcinoma, Renal Cell ; Diagnosis, Differential ; Epithelioid Cells ; Female ; Follow-Up Studies ; Humans ; Kidney ; Melanins ; Melanoma ; Perivascular Epithelioid Cell Neoplasms ; Pigmentation ; Prognosis ; Tuberous Sclerosis

Epithelioid angiomyolipoma (EAML) of liver is a rare neoplasm. Hepatic EAML is often misdiagnosed as other neoplasms such as hepatocellular carcinoma due to non-specific clinical and radiologic features. The morphologic features under microscope and immunohistochemistry staining profile are important in the diagnosis EAML. Here, we report a case of 52-year-old man who found 1.2 cm mass in liver by routine checkup. On the impression of hepatocellular carcinoma, lateral sectionectomy of the liver was done. Microscopically, the tumor is composed of predominant epithelioid cells with vascular component and foamy cells. These cells were positive for HMB45, MelanA, and smooth muscle actin and negative for epithelial membrane antigen. The final diagnosis was hepatic EAML.
Actins ; Angiomyolipoma* ; Carcinoma, Hepatocellular ; Diagnosis ; Epithelioid Cells ; Humans ; Immunohistochemistry ; Liver* ; MART-1 Antigen ; Middle Aged ; Mucin-1 ; Muscle, Smooth ; Perivascular Epithelioid Cell Neoplasms

Angiomyolipomas are hamartomatous lesions consisting of smooth muscle bundles, thick-walled blood vessels, and mature adipocytes. They are usually found in the kidneys of tuberous sclerosis patients and more rarely in other organs, such as the liver, the oral cavity, the sinonasal tract, the heart, the large intestines, the lungs, and the skin. Cutaneous angiomyolipoma has shown to be very rare and generally occurs at the ends of the digits, the elbows, the ears, and the nose. Herein, we report the first documented case of angiomyolipoma of the glabellar region.
Adipocytes ; Angiomyolipoma* ; Blood Vessels ; Ear ; Elbow ; Heart ; Humans ; Intestines ; Kidney ; Liver ; Lung ; Mouth ; Muscle, Smooth ; Nose ; Perivascular Epithelioid Cell Neoplasms ; Skin ; Tuberous Sclerosis

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

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