Mixed pulmonary blastoma and carcinosarcoma

Review article: pulmonary sarcomatoid carcinomas: a practical overview

Pulmonary sarcomatoid carcinomas (PSCs) are currently defined as poorly differentiated non-small-cell carcinomas containing a component with sarcoma or sarcoma-like (spindle and/or giant cell) features. They consist of 5 major histological variants, namely pleomorphic carcinoma, spindle cell carcinoma, giant cell carcinoma, carcinosarcoma, and pulmonary blastoma. The segregation of PSCs into a distinct clinicopathologic entity seems justified on the basis of morphologic, behavioral, and genotypic/phenotypic attributes. As a group, PSCs generally run an aggressive clinical course and may cause major difficulties in the differential diagnosis with other primary and secondary malignancies of the lung. At present, PSCs are believed to represent a family of carcinomas "in transition," in which diverse pathways of clonal evolution account for histological differences of a common ancestor lesion. The sarcomatous or sarcomatoid component of these tumors is thought to derive from carcinoma cells during the progression of carcinogenesis through the activation of an epithelial-mesenchymal transition program leading to sarcomatous transformation or metaplasia (conversion paradigm). Conceivably, targeting the epithelial-mesenchymal transition program could become a valid therapeutic strategy for these life-threatening tumors, whose sensitivity to current medical manipulation is disappointing.

Blastomatous tumor with teratoid features of nasal cavity: report of a case and review of the literature

A case of blastomatous tumor with teratoid features is presented. The polypoid mass was observed in the left nasal cavity of a 72-year-old man. Histologically, the lesion was composed of neuroepithelial cells with blastomatous appearance, cystic squamous nests filled with keratin materials, many mucous glands, complex tubular and glandular structures with edematous fibroblastic stroma. Sinonasal neoplasms including teratoid components and immature neuroepithelium are exceedingly rare. We suggest that the term 'immature teratoma' is more suitable than blastoma or blastomatous tumor when there is no carcinomatous or sarcomatous component besides the immature neuroepithelium and teratoid elements.