American Journal of Epidemiology

American Journal of Epidemiology © The Author 2007. Published by the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org.

Original Contribution

Cellular Phone Use and Risk of Benign and Malignant Parotid Gland Tumors—A Nationwide Case-Control Study

Siegal Sadetzki^1,2, Angela Chetrit¹, Avital Jarus-Hakak¹, Elisabeth Cardis³, Yonit Deutch¹, Shay Duvdevani⁴, Ahuva Zultan¹, Ilya Novikov⁵, Laurence Freedman⁵ and Michael Wolf^2,4

¹ Cancer and Radiation Epidemiology Unit, Gertner Institute, Chaim Sheba Medical Center, Tel Hashomer, Israel
² Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
³ Radiation Group, International Agency for Research on Cancer, Lyon, France
⁴ Department of Otolaryngology–Head and Neck Surgery, Chaim Sheba Medical Center, Tel Hashomer, Israel
⁵ Biostatistics Unit, Gertner Institute, Chaim Sheba Medical Center, Tel Hashomer, Israel

Correspondence to Dr. Siegal Sadetzki, Cancer and Radiation Epidemiology Unit, Gertner Institute, Chaim Sheba Medical Center, Tel Hashomer 52621, Israel (e-mail: siegals@gertner.health.gov.il ).

Received for publication March 1, 2007. Accepted for publication October 8, 2007.

The objective of this nationwide study was to assess the association between cellular phone use and development of parotid gland tumors (PGTs). The methods were based on the international INTERPHONE study that aimed to evaluate possible adverse effects of cellular phone use. The study included 402 benign and 58 malignant incident cases of PGTs diagnosed in Israel at age 18 years or more, in 2001–2003, and 1,266 population individually matched controls. For the entire group, no increased risk of PGTs was observed for ever having been a regular cellular phone user (odds ratio = 0.87; p = 0.3) or for any other measure of exposure investigated. However, analysis restricted to regular users or to conditions that may yield higher levels of exposure (e.g., heavy use in rural areas) showed consistently elevated risks. For ipsilateral use, the odds ratios in the highest category of cumulative number of calls and call time without use of hands-free devices were 1.58 (95% confidence interval: 1.11, 2.24) and 1.49 (95% confidence interval: 1.05, 2.13), respectively. The risk for contralateral use was not significantly different from 1. A positive dose-response trend was found for these measurements. Based on the largest number of benign PGT patients reported to date, our results suggest an association between cellular phone use and PGTs.

case-control studies; cellular phone; head and neck neoplasms; Israel; parotid gland

Abbreviations: CI, confidence interval; OR, odds ratio; PGT, parotid gland tumor; UICC, Union Internationale Contre le Cancer