Contact With Ruminants Is Associated With Esophageal Squamous Cell Carcinoma Risk Publisher Pubmed



Nasrollahzadeh D^{1, 2} ; Ye W¹ ; Shakeri R² ; Sotoudeh M² ; Merat S² ; Kamangar F³ ; Abnet CC⁴ ; Islami F^{2, 5} ; Boffetta P⁵ ; Dawsey SM⁴ ; Brennan P⁶ ; Malekzadeh R² Show Affiliations
Source: International Journal of Cancer Published:2015

Abstract

The etiology of esophageal squamous cell carcinoma (ESCC) in the high risk area of northern Iran is only partially known. We aimed to investigate prolonged animal contact as a risk factor for ESCC in this population. From 2003 to 2007, we administered a validated questionnaire to 300 ESCC cases and 571 randomly selected controls matched for neighborhood of residence, age (±2 years) and sex. Questions on lifelong exposure to equines, ruminants, canines, and poultry, including duration and level of contact, were asked in a face-to-face interviews. Conditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) adjusted for potential confounders. A total of 94.7% of cases and 68.7% of controls reported lifelong history of contact with ruminants. After controlling for potential confounders, contact with ruminants was associated with an eightfold increase (95% CI: 3.92-14.86) in risk of ESCC, and increments in duration of contact raised the risk estimates in a dose-dependent manner. Contact with equines and poultry did not significantly change associated OR for ESCC risk and contact with ruminants. OR (95% CI) for contact with canines was 1.99 (1.35-2.93) which after exclusion of contact with ruminants was not significant (OR for contact only with canine: 3.18, 95% CI: 0.73-13.17). These results add to the evidence that contact with ruminants may increase the risk of ESCC. © 2014 UICC.