Get full text report (pdf file; Read by ADOBE Acrobat Reader)
J Occup Health year 2004 volume 46 number 5 page 398 - 402
Classification Original
Title Liver Cancer Risk in Japanese Male Dentists: A Long-Term Retrospective Cohort Study
Author Hideo TANAKA1, Nobuhiro NISHIO2, Rikio TOKUNAGA2 and Hideaki TSUKUMA1
Organization 1Department of Cancer Control and Statistics, Osaka Medical Center for Cancer and Cardiovascular Diseases and 2Department of Hygiene, Kansai Medical University, Japan
Keywords Dentist, Liver cancer, Cancer registry, Incidence, Retrospective cohort study
Correspondence H. Tanaka, Department of Cancer Control and Statistics, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka 537-8511, Japan (e-mail: tanaka-hi@mc.pref.osaka.jp)
Abstract Liver Cancer Risk in Japanese Male Dentists: A Long-Term Retrospective Cohort Study: Hideo TANAKA, et al. Department of Cancer Control and Statistics, Osaka Medical Center for Cancer and Cardiovascular Diseases-It has been speculated that dentists are at high risk for occupational exposure to bloodborne viruses such as hepatitis B and hepatitis C viruses. To assess the risk of the development of liver cancer among Japanese male dentists, we conducted a retrospective cohort study on 3,314 dentists of the Osaka Dental Association who were members between 1964 and 1985, the year before HBV immunization became available. By linking to the Osaka Cancer Registry, we found that during the period of 1964-1997, 36 of the dentists were diagnosed with liver cancer over a mean follow-up of 23.6 yr. The observed number of liver cancer cases was compared with the expected number, which was calculated by multiplying the number of person-years at risk by the corresponding age- and calendar time-specific incidence rate from the Osaka Cancer Registry data. The male dentists had a significantly lower risk of developing liver cancer than the general population of Osaka (O/E=0.71, 95% CI=0.50-0.98). On subcategorical analysis by birth year or duration of follow-up, there was no significantly increased risk of developing liver cancer among the dentists. Contrary to our expectation, our findings indicate that Japanese dentists were not at increased risk of developing liver cancer compared with the general population.