Opium Use and Head and Neck Cancers: A Matched Case-Control Study in Iran.

Head and Neck (H and N) cancers include malignant tumors of the nasal cavity, pharynx, paranasal sinuses, oral cavity, larynx and salivary glands. Opium use might be related to these cancers. The aim of this study was to investigate the relation between Opium and its Derivatives (O and D) use and the incidence of H and N cancers.In this case-control study conducted in Kerman, 140 patients with HandN cancers and 280 healthy controls (matched for age, gender, and place of residence) were included. Information about their use of OandD, cigarette smoking, alcohol and diet were collected using a structured questionnaire. Conditional logistic regression was used to investigate the relation between variables.The use of opioids was associated with an increased risk of HandN cancers (Adjusted OR: 8.13; CI: 4.08-16.2). A significant dose-response relation between OandD use was observed, with high use Adjusted OR=8.91; 95% CI: 4.03-19.65 and low use Adjusted OR=6.52; 95% CI: 3.18- 13.36. This dose-response association was stronger in patients with laryngeal cancer and opioids use, with high use Adjusted OR = 11.17; 95% CI=4.48-28.09 and low use Adjusted OR = 9.46; 95% CI= 3.97- 22.52.The results show that opium use can be considered as an important risk factor for H and N cancers. Also in Iran, opium seems to play a more important role than cigarette smoking.