A morphologic and immunohistochemical study of nasal mucosa in leatherworkers.

Background: The association between intestinal-type sinonasal adenocarcinoma and the occupational exposure to leather dusts has been widely documented, but the identification of precursor lesions in exposed workers has remained controversial. The purpose of this study was to investigate the histological changes and modifications in the phenotype of epithelial cells in nasal mucosa of leather workers.

Methods: Biopsy specimens of the mucosa of the middle turbinate were obtained from 139 subjects who had been employed in leather factories for 10-48 years (median, 29 years). Tissue fragments were routinely processed for histological examination and immunostainings for cytokeratin 20, CDX-2, and MUC-2 were performed.

Results: Regarding the surface epithelium, the most common histopathological finding was the presence of squamous metaplasia (64.7%), which was associated with mild to moderate dysplasia in 37 cases (41.1%), and goblet cell hyperplasia was identified in 30 biopsy specimens (21.6%). Positivity for MUC-2 was detected in goblet cells of 20 of the 30 samples with goblet cell hyperplasia (66.6%), whereas no immunostaining was observed for cytokeratin 20 and CDX-2. Presence of goblet cell hyperplasia was significantly associated with longer occupational exposure in leather tanning activities (p = 0.03). None of the alterations observed (squamous metaplasia, dysplasia, or goblet cell hyperplasia) showed correlation with smoking habits. Similarly, there was no correlation between squamous metaplasia with or without dysplasia and type and duration of occupational exposure.

Conclusion: Our data identify goblet cell hyperplasia as possible work-related alterations of nasal mucosa in leather workers. Additional investigations are needed to clarify the significance of these findings in the development of sinonasal intestinal-type carcinoma.