Incidence of testicular cancer and occupation among Swedish men gainfully employed in 1970

PURPOSE: To estimate occupation-specific risk of seminomas and nonseminoma subtypes of testicular cancer among Swedish men gainfully employed in 1970 over the period 1971-1989. METHODS: Age-period standardized incidence ratios were computed in a datase t linking cancer diagnoses from the Swedish national cancer register to occ upational and demographical data obtained in the census in 1970. Log-linear Poisson models were fitted, allowing for geographical area and town size. Taking occupational sector as a proxy for socioeconomic status, occupationa l risks were recalculated using intra-sector analyses, where the reference group comprised other occupations in the same sector only. Risk estimators per occupation were also computed for men reporting the same occupation in 1960 and 1970, a more specifically exposed group. RESULTS: Seminomas and nonseminomas showed a substantial geographical varia tion, The association between germ-cell testicular tumors and high socioeco nomic groups was found mainly for nonseminomas. Positive associations with particular occupations were more evident for seminomas, for which railway s tationmasters, metal annealers and temperers, precision toolmakers, watchma kers, construction smiths, and typographers and lithographers exhibited a r isk excess. Concrete and construction worker was the only occupation consis tently associated with nonseminomas. CONCLUSIONS: Among the many occupations studied, our results corroborate th e previously reported increased risk among metal workers, specifically rela ted with seminomatous tumors in this study. Our results confirm the geograp hical and socioeconomical differences in the incidence of testicular tumors . These factors should be accounted for in occupational studies. The differ ent pattern of occupations related with seminomas and nonseminomas support the need to study these tumors separately. (C) 2001 Elsevier Science Inc. A ll rights reserved.