title: Risk factors associated with nasopharyngeal carcinoma.
abstract: We performed a case-control study of nasopharyngeal squamous-cell carcinoma to identify risk factors associated with the disease. Interviews with 156 patients and 267 controls revealed that increased risk was significantly associated with a prior history of ear, nose or throat disease (relative risk = 1.8, P = 0.006) and occupational exposure to fumes (relative risk = 2.0, P = 0.006), smoke (relative risk = 3.0, P = 0.008) and chemicals (relative risk = 2.4, P = 0.006). Among Chinese, other Asians and Mexican-Americans, increased risk was also associated with foreign birthplace (relative risk = 2.1, P = 0.04), probably reflecting childhood exposure to carcinogens in inhaled smoke. In Chinese patients the risk associated with foreign birthplace and occupational exposure increased among those with HLA-A2 and less than two antigens at the B locus, suggesting a genetic variation in susceptibility.
mesh_terms: D000328:Adult; D000368:Aged; D001208:Asia / Q000208:ethnology; D044466:Asian People; D002140:California; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000235:genetics; D002681:China / Q000208:ethnology; D004781:Environmental Exposure; D004785:Environmental Pollutants; D005006:Ethnicity; D005260:Female; D006680:HLA Antigens; D006801:Humans; D008297:Male; D008800:Mexico / Q000208:ethnology; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology* / Q000235:genetics; D012306:Risk; D012907:Smoking / Q000150:complications; D044465:White People
chemical_list: D004785:Environmental Pollutants; D006680:HLA Antigens