1. ¹Division of Epidemiology and Public Health, University of Nottingham Medical School, Queens Medical Centre, Nottingham NG7 2UH, UK
2. ²The Royal Marsden NHS Foundation Trust, Fulham Road, SW3 6JJ, UK
3. ³CR-UK Genetic Epidemiology Unit, Strangeways Research Laboratories, Worts Causeway, Cambridge CB1 8RN, UK
4. ⁴Cancer Research UK Epidemiology Unit, University of Oxford, Richard Doll Building, Roosevelt Drive, Oxford OX3 7LE, UK
5. ⁵BAUS Section of Oncology, London WC2A 3PE, UK
6. ⁶The Institute of Cancer Research, Sutton, Surrey SM2 5NG, UK
7. ⁷The Chulabhorn Cancer Hospital, Bangkok, 10210, Thailand
8. ⁸University Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK

Correspondence: Dr K Muir, E-mail: kenneth.muir@nottingham.ac.uk

⁹Joint senior authors

Received 22 February 2008; Accepted 20 March 2008; Published online 13 May 2008.

Abstract

Exposure to ionising radiation is an established risk factor for many cancers. We conducted a case–control study to investigate whether exposure to low dose ionisation radiation from diagnostic x-ray procedures could be established as a risk factor for prostate cancer. In all 431 young-onset prostate cancer cases and 409 controls frequency matched by age were included. Exposures to barium meal, barium enema, hip x-rays, leg x-rays and intravenous pyelogram (IVP) were considered. Exposures to barium enema (adjusted odds ratio (OR) 2.06, 95% confidence interval (CI) 1.01–4.20) and hip x-rays (adjusted OR 2.23, 95% CI 1.42–3.49) at least 5 years before diagnosis were significantly associated with increased prostate cancer. For those with a family history of cancer, exposures to hip x-rays dating 10 or 20 years before diagnosis were associated with a significantly increased risk of prostate cancer: adjusted OR 5.01, 95% CI 1.64–15.31 and adjusted OR 14.23, 95% CI 1.83–110.74, respectively. Our findings show that exposure of the prostate gland to diagnostic radiological procedures may be associated with increased cancer risk. This effect seems to be modified by a positive family history of cancer suggesting that genetic factors may play a role in this risk association.