Case-series investigation of intracranial neoplasms at a petrochemical research facility

Background: From 1970 through 1997, 17 intracranial neoplasms were identified among 6,800 employees of a petrochemical research facility. This investigation describes the case-series. Methods The intracranial neoplasms were identified by self reports and record linkages, and were confirmed by medical records and a pathology review. Standardized incidence ratios (SIRs) compare observed and expected numbers of cases according to certain work characteristics. Results: Overall, there were 17 observed and 10.5 expected intracranial neoplasms, including 11/4.7 benign intracranial tumors and 6/5.9 brain cancers. All brain cancers occurred among male research scientists or technicians. Four had worked at some time on the same floor of one building (SIR = 12.6, 95% CI = 3.4-32.1), and several had worked on a research project with at least one other brain cancer case. The benign intracranial neoplasm cases did not have common building assignments or work activities. Conclusions The occurrence pattern of brain cancers, but not that of benign tumors, suggests a possible occupational etiology.