Nasal cavity neoplasms

Formaldehyde has been shown to be carcinogenic in two strains of rats, resulting in squamous cell cancers of the nasal cavity after repeated inhalation of about 14 ppm. In one study, 51 of 117 male and 42 of 115 female Fischer 344 rats developed this tumor, but no nasal tumors were seen at 0 or 2 ppm. No other neoplasm was increased significantly. In a similar study of mice, this nasal tumor occurred in two male mice at 14.3 ppm. None of the excesses was statistically significant except for the high-exposure rats. °... 

Formaldehyde 1986 Limited O, E Not specified Respiratory neoplasms Y (nasal cavity squamous... 

Respiratory Tract. While neoplasms of the same cell of origin in the larynx, trachea, and major bronchi would usually be combined, neoplasms of the peripheral lung (bronchiolar-alveolar neoplasms) would be analyzed separately. Similarly, neoplasms of the nasal cavity would not normally be combined with those found in the rest of the respiratory tract. 

Many of the tumors of the nasal cavity and paranasal sinuses fall under the category of round cell neoplasms. Among these are olfactory neuroblastoma, sinonasal undifferentiated carcinoma, malignant melanoma, neuroendocrine carcinoma-small cell neuroendocrine carcinoma, malignant lymphoma, extramedullary plasmacytoma, invasive-ectopic pituitary adenoma, rhabdomyosarcoma, and Ewing s sarcoma (ES)-peripheral neuroectodermal tumor (ES/ PNET). But there is also a host of other epithelial lesions that are unique to the sinonasal tract. 

Some poorly differentiated human sinonasal neoplasms (neuroblastoma, neuroectodermal mmors) express the ancient achaete-scute genes/gene-product proteins. This finding was interpreted as a nonspecific marker for diagnosis [1751, 1752]. Esthesioneuroblastoma of the nasal cavity and the paranasal sinuses express upregulated Mashl [1753, 1754]. The Mash proteins may be the driving force of these mmors. 

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