Angioleiomioma oral: relato de um caso e revisão dos achados atuais / Oral angioleiomyoma: case report and a review of current findings

Resumo O angioleiomioma é uma neoplasia benigna que, a partir da nova classificação da OMS (2013) para os tumores de tecidos moles, deixou de ser considerado um tumor de origem muscular lisa, passando a ser considerado um tumor de origem perivascular. Raramente os angioleiomiomas ocorrem na cavidade oral. A lesão é tratada cirurgicamente, com prognóstico considerado favorável. Este trabalho revisa os casos de angioleiomioma oral relatados na literatura nos últimos 5 anos e descreve esse tumor em um homem de 44 anos que apresentou um nódulo assintomático localizado em lábio superior, com evolução de 6 meses. As hipóteses diagnósticas foram de adenoma pleomórfico e adenoma canalicular. A lesão foi submetida à biópsia e análise histopatológica e imuno-histoquímica (S100, CD34, α-SMA, H-caldesmon e desmina) confirmaram o diagnóstico de angioleiomioma. Destacamos a imuno-histoquímica como um importante método auxiliar no diagnóstico diferencial do angioleiomioma com outras lesões e, principalmente, com o miopericitoma.

Abstract Angioleiomyoma is a benign neoplasm that was considered a tumor of smooth-muscle origin until the most recent (2013) WHO classification of soft tissue tumors, in which it was reclassified as a tumor of perivascular origin. Angioleiomyomas rarely occur in the oral cavity. These lesions are treated surgically with good prognosis. This article presents a review of reports of oral angioleiomyoma in the literature from the last 5 years and describes the case of a 44-year-old man who presented with an asymptomatic nodule in the upper lip that had developed over a 6-month period. Diagnostic hypotheses of pleomorphic adenoma or canalicular adenoma were raised. Biopsy of the lesion, histopathological and immunohistochemical analysis (S100, CD34, H-caldesmon, and desmin) confirmed a diagnosis of angioleiomyoma. It is noteworthy that immunohistochemistry is an important auxiliary method for differential diagnosis of angioleiomyoma from other tumors, particularly myopericytoma.

A Case of Malignant Perivascular Epithelioid Cell Tumor of the Retroperitoneum with Multiple Metastases / 대한소화기학회지

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.

Uncommon of the Uncommon: Malignant Perivascular Epithelioid Cell Tumor of the Lung

A perivascular epithelioid cell (PEC) tumor is a rare mesenchymal tumor characterized by abundant cytoplasmic Periodic acid-Schiff positive glycogen (also called sugar tumor or clear cell tumor of the lung for this characteristic) and is mostly benign. We report a case of a 63-year-old man who presented with an enlarging mass on chest radiograph. After a thorough workup, diagnosis of malignant pulmonary PEC tumor with lung to lung metastases was established. Herein, the difficulties of diagnosis and management we confronted are described.

Retroperitoneal sclerosing PEComa with melanin pigmentation and granulomatous inflammation-A rare association within an uncommon tumor.

PEComa, defined as a perivascular epithelioid cell tumor, displays a wide clinicopathological spectrum. Lately, a sclerosing PEComa has been identified as its distinct variant, but with limited documentation, in view of its rarity. Herein, we describe an uncommon case of a 53-year-old lady, who was referred to us with pain abdomen. Radiological imaging disclosed a well-defined, hypodense retroperitoneal mass. The excised tumor was a round, encapsulated soft tissue mass measuring 7 cm with a tan-brown cut surface. Microscopy showed uniform, epithelioid cells with clear cytoplasm, focal melanin pigmentation and mild nuclear atypia, arranged in sheets and nests around capillary-sized vessels in a dense sclerotic stroma. Additionally, co-existing epithelioid granulomas were noted. On immunohistochemistry (IHC), tumor cells were diffusely positive for HMB45; focally for desmin and smooth muscle actin (SMA), while negative for EMA, CD10, S100-P, Melan A, CD34, AMACR and CK MNF116. This case reinforces sclerosing PEComa as an uncommon, but a distinct clinicopathological entity and exemplifies diagnostic challenge associated with it; necessitating application of IHC markers for its correct identification. Presence of melanin pigment and granulomatous inflammation in the present tumor constitute as novel histopathological findings in a sclerosing PEComa.

A Case of a Perivascular Epithelioid Cell Tumor Mimicking Colon Cancer / 대한소화기학회지

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.

Perivascular Epithelioid Cell Tumor (PEComa) of Abdominal Cavity from Falciform Ligament: A Case Report

We present a case of perivascular epithelioid cell tumors (PEComas) in the abdominal cavity at the falciform ligament. A 30-yr-old Korean man visited to hospital for the evaluation of a growing, palpable abdominal mass. He had felt the mass growing over 6 months. There was no family or personal history of tuberous sclerosis. The resected specimen showed a mass of 8.0x7.0x5.5 cm in size. Histological examination showed sheets of spindle-to-epithelioid cells with clear-to-eosinophilic cytoplasm. Immunohistochemically, tumor cells were positive for HMB-4 (gp100) and smooth muscle actin. They were also positive for the S-100, which is a marker of neurogenic and melanocytic tumors. Patient was treated with radical resection of tumor without any adjuvant therapy. He is well and on follow-up visits without tumor recurrence.

Clear Cell "Sugar" Tumor of the Lung: A Well-Enhanced Mass with an Early Washout Pattern on Dynamic Contrast-Enhanced Computed Tomography

Clear cell tumor of the lung is a rare and very unusual benign pulmonary tumor. As clear cell tumor of the lung contains abundant cytoplasmic glycogen, this tumor is called "sugar tumor". We report a case of sugar tumor in a 64-yr-old man presenting as a round pulmonary nodule. On dynamic computed tomography (CT) scans, the solitary pulmonary nodule showed early wash-in enhancement with an early washout pattern like a lung malignancy. The patient underwent wedge resection for the tumor. Pathologic examination, including immunohistochemical studies, revealed that the nodule was a benign clear cell tumor, so-called "sugar tumor". Because only a small number of cases have been reported previously, clinical aspects, radiological characteristics on dynamic contrast-enhanced CT, and differential diagnosis of the tumor are not well established. Herein we present a clear cell tumor of the lung and discuss the clinical, radiological, and pathological features of the tumor.