Analysis of clinicopathologic features and expression of NR4A3 in sinonasal acinic cell carcinoma

Sinonasal Adenocarcinomas: An Update

Among sinonasal malignancies, adenocarcinomas account for the second most common entity after squamous cell carcinoma. They span a wide spectrum of neoplasms with heterogeneous features including intestinal-type adenocarcinoma (ITAC), non-intestinal-type adenocarcinomas (non-ITACs), and salivary-type adenocarcinomas. ITAC basically mirrors the histopathological aspects of gastrointestinal counterparts, showing variable tubulo-papillary, colonic, and mixed patterns with mucin production in 20% to 25% of cases. By contrast, non-ITACs do not show any differentiation toward intestinal or salivary phenotype, and they mainly represent a diagnosis of exclusion lacking a proper histopathological and molecular definition.

DOG-1 positive primary acinic cell carcinoma of the lung and investigation of molecular status

Primary acinic cell carcinoma (ACC) of the lung is an extremely rare neoplasm that more often arises near to a right bronchus. It is characterized by two populations of clear and dark eosinophilic cells, arranged in a glandular acinar pattern. Mitosis are rare and tumor cells show small and eccentric nuclei. Positive stain for PAS, PAS-D, cytokeratin, A1AT and A1ACT is reported, while TTF1, p40, synaptophysin, SMA, and S100 are substantially negative. DOG-1 positive stain was observed in ACC of the salivary glands and its negativity was proposed to distinguish between primary and metastatic ACC of the lung. Here, we report the 30th case of primary ACC of the lung, describing the immunohistochemical positivity for DOG-1 and the molecular status of the neoplasm for the first time.