Primary pulmonary meningioma may arise from meningothelial-like nodules.

A rare case of primary pulmonary meningioma, associated with meningothelial-like nodules in the same lung resection, with preoperative fine needle aspiration cytological findings and ultrastructural features, is described. The simultaneous presence of meningioma and meningothelial-like nodules, never before described, corroborates the unifying hypothesis of their common origin and nature.

Carcinosarcoma of the parotid gland: cytological, clinicopathological and immunohistochemical study of a case.

Manifesting a putative origin from a pleomorphic adenoma, carcinosarcoma of the salivary gland is a heterologous neoplasm in which a sarcomatous and a carcinomatous component coexist. We present a parotid gland carcinosarcoma in a 77-year-old man with peculiar morphological findings. Fine-needle aspiration cytology allowed a preoperative diagnosis of poorly differentiated carcinoma. At histologic examination, the tumor showed biphasic differentiation with an epithelial component made up of well-differentiated keratinizing squamous carcinoma and ductal-type adenocarcinoma, and a mesenchymal component, revealing focal areas of osteosarcoma and myoepithelial malignant proliferation. Carcinosarcoma is a very rare malignant neoplasm, accounting for 0.16% of malignant salivary gland tumors: only 60 cases have been reported, some of which arose "de novo", i.e., without clinico-pathologic evidence of a pre- or co-existing pleomorphic adenoma.

Gastrointestinal autonomic nerve tumor (plexosarcoma): report of a case with fine needle aspiration biopsy and histologic, immunocytochemical and ultrastructural study.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) encompass a large group of mesenchymal neoplasms that display common cytologic spindle-shaped morphology on light microscopy. Immunocytochemical and ultrastructural studies can demonstrate several patterns of differentiation. CASE: A 70-year-old male presented with two intraabdominal small bowel masses. The cytopathologic features of a fine needle aspiration biopsy (FNAB) included plump spindle cells in densely populated aggregates or in a fasciculated pattern, without significant pleomorphism. An epithelioid component in a lobular arrangement with abundant, eosinophilic cytoplasm was also noted. The nuclei were vesicular, with a very evident, eosinophilic nucleolus and finely distributed chromatin. Groups of loosely cohesive cells with slender, dendritic-like cytoplasm were evident. Immunocytochemical study of the embedded, fine needle aspirated fragments of the neoplasm demonstrated immunoreactivity for vimentin and neuron-specific enolase. Cytokeratin immunoreactivity or muscular, vascular, neuroendocrine or nerve sheath differentiation failed to be demonstrated. The cytologic and immunocytochemical findings correlated well with the histologic features of the neoplasm. The morphologic diagnosis was confirmed by ultrastructural study. CONCLUSION: FNAB and immunocytochemistry can be valuable in making the correct diagnosis between gastrointestinal stromal tumors.

Conclusive diagnosis of hepatic and pancreatic malignancies by fine needle aspiration.

A study of the diagnosis of hepatic and pancreatic malignancies by fine needle aspiration (FNA) was made, based on 221 aspirates obtained from 209 patients with histologic or clinical confirmation: 159 with hepatic and 50 with pancreatic lesions. The values of sensitivity, specificity and predictivity for positive FNA results were, respectively, 0.84, 0.96 and 1.0 for the liver and 0.76, 1.0 and 1.0 for the pancreas. The composition of the case material showed an incidence of malignant tumors of the liver and pancreas of 84% and 60%, respectively (among which the primary malignancies were 39% and 48%), while nonneoplastic lesions had incidences of 14% and 40%. However, conclusive FNA diagnoses of the histologic type of the primary and the site of origin of metastatic tumors were made in 60% of the hepatic lesions but in only 9% of the pancreatic lesions. Primary hepatocellular carcinoma was diagnosed by FNA of the liver in 95% of the cases; FNA specifically diagnosed 42% of intrahepatic bile duct carcinomas and 40% of hepatic metastases. These findings correlate with the unique cytologic features of primary hepatocellular carcinoma of intrahepatic rather nonspecific morphology of carcinoma of intrahepatic and extrahepatic origin, as well as of pancreatic ductal origin.