Trial Information

A Case-Referent Study of Brain Tumors in Adults

The etiology of brain tumors is poorly understood. Due, in part, to public concern about a
postulated relationship between the use of cellular telephones or other increasingly
prevalent environmental exposures and the incidence of brain cancer in adults. The National
Cancer Institute is collaborating with three US hospitals in a comprehensive case-control
study of malignant and benign brain tumors. Factors under consideration include the use of
cellular phones and other wireless communication devices, workplace exposures to chemical
agents and electromagnetic fields, dietary factors, family history of tumors, genetic
determinants of susceptibility, home appliance use, reproductive history and hormonal
exposures, viruses, medical and dental exposures to ionizing radiation, and other aspects of
medical history.

Approximately 800 newly diagnosed brain tumor cases and 800 controls have been enrolled at
hospitals in Boston, Phoenix, and Pittsburgh. Cases include all adults (age age greater than
or equal to 18 years) newly diagnosed with a histologically confirmed intracranial giloma,
intracranial meningioma or acoustic neuroma. Controls are patients admitted to the same
hospitals as the cases, and treated for any of a variety of non-malignant conditions.
Participating cases and controls were interviewed in the hospital by a research nurse and
asked to complete a self-administered questionnaire and donate a sample of blood. Key
features of the study include its large size, the emphasis on rapid ascertainment of
incident cases and interview of study subjects rather than surrogate respondents, the use of
detailed, job-specific questions developed by industrial hygienists to ascertain
occupational exposures and gene-environment interactions.

Implementation of the study protocol proceeded without serious problems. There have been no
harmful effects on study participants. There have been no complaints from participants or
breaches of confidentiality. Continuation of this research involves analysis and reporting
of results. Numerous publications have resulted from the study and analyses are ongoing.