Conclusions

The main focus of this study was to look at brain cancer deaths and associated employment in North Carolina.

Phase 1
Phase 1 involved records matching.

• Misclassification on Death Certificates
  Records of 1995 brain cancer patients from the N.C. Central Cancer Registry files were matched to death certificates in order to determine how many are being misclassified on the death certificate. It was suspected that since the brain is a site in the body where a primary cancer frequently spreads (metastasis), many death certificates therefore would be miscoded. Indeed, 7.5% of the death certificates were found to have been from patients whose first cancers arose elsewhere in the body.
  Information from Death Certificates coded as Brain Cancer should be used cautiously because of misclassification due to metastasis.

• Missing Data
  It is optional for facilities submitting cancer patient records to the N.C. Central Cancer Registry to send information about work history (i.e., usual occupation), although many choose not to. Registry information on occupation, when available, compared favorably to the occupation and industry codes found on the death certificates.
  Registry records, however, are only marginally useful for occupation/industry-based risk or exposure studies, since data are frequently missing.

Phase 2
Phase 2 involved studying 10 years' worth of brain cancer death certificates to determine the occupations and industries most highly associated with brain cancer death. These were compared in a case-control fashion to employment information for non-cancer deaths by race and sex.

• As in other studies, risk of brain cancer death was found in various white collar professions such as education, accounting, law, and dentistry.

• Increased risk was also found for white males in professions associated with electronics and for minority males employed in automobile repair.
  Results should be interpreted with caution, since it is not known how long a person worked in the field represented on the death certificate. There are numerous professions that have been associated with the development of brain cancer, only a few of which have been proven conclusively.