PHYSICAL-ACTIVITY, MEDICAL HISTORY, AND RISK OF TESTICULAR CANCER (ALBERTA AND BRITISH-COLUMBIA, CANADA)

In order to evaluate risk factors for germ cell cancers, we conducted a case-control study of 510 men with testicular cancer aged 15 to 79 y ears and 996 randomly selected age-matched controls in the provinces o f British Columbia and Alberta, Canada. Subjects completed a mailed qu estionnaire providing data on education level, ethnic origin, medical history, smoking, occupation, and recreational and sports activity. Th e response rate among cases was 80.3 percent and among controls was 68 .1 percent. After controlling for age and ethnic origin, undescended t estis was associated positively with risk of testicular cancer (odds r atio [OR]=3.5; 95 percent confidence interval [CI]=2.2-5.7) as was ing uinal hernia requiring surgery (OR=2.0, CI=1.3-2.9), and hydrocoele (O R=2.6, CI=1.4-5.1). Risk of testicular cancer increased with height, w ith subjects taller than 180 cm having a significantly increased risk compared with those 174 cm or less (OR=1.5, CI=1.1-2.1). A moderate to high level of recreational activity level was associated inversely wi th testicular cancer risk (OR=0.6, CI=0.5-0.8).