Occupational risk factors for sino-nasal cancer

Introduction
Sino-nasal cancer has been consistently associated with exposure to wood dust, leather dust, nickel and chromium compounds, whereas for other occupational hazards, the findings are somewhat mixed. The aim of this study was to investigate the risk of sino-nasal epithelial cancer (SNEC) by histological type with prior exposure to suspected occupational risk factors and, in particular, those in metalworking.

Methods
Between 1996 and 2007, incident cases were collected on a monthly basis from hospitals throughout the Piedmont region of Italy by the regional Sino-nasal Cancer Registry. A questionnaire on occupational history, completed by 235 cases and 336 hospital controls, was used to assign exposure to a list of occupational hazards. The relationship between SNEC and cumulative exposure to occupational hazards was explored using unconditional logistic regression adjusted for age, gender, smoking and co-exposures, allowing for a 10-year latency period.

Results
The risk of adenocarcinoma was significantly increased with ever-exposure to wood dust (OR=58.9), leather dust (OR=34.3), organic solvents (OR=4.0) and textile dusts (OR=3.9), whereas ever-exposure to welding fumes (OR=3.8) significantly increased the risk for squamous cell carcinoma. For a mixed group of other histological types, a significant association was found with wood dust (OR=3.0), organic solvents (OR=4.4), textile dusts (OR=3.7) and strong acid mists (3.8). For all these hazards, significant dose-response relationships were observed between the risk of developing each histological type and cumulative exposure on a continuous scale.

Discussion
Some occupational risk factors for SNEC were confirmed, and dose–response relationships were observed for other hazards that merit further investigation. The results of this study mainly confirm those obtained from a previous analysis (d’Errico et al., 2009), which included only about half of the cases available in the present one. However, the number of cases exposed to the different agents increased substantially, providing greater robustness to our findings.