1.97), breast cancer (HR=1.45, 95% CI=1.00, 2.09), and non-cervical gynecological cancer (HR=4.03, 95% CI=1.77, 9.17), compared with the general population. Conclusions: Physicians are at lower overall risk of cancer than the general population, apart from cancer of the thyroid, prostate, breast, and non-cervical gynecological cancer. (J Occup Health 2013; 55: 158−166) Key words: Cancer incidence, Cohort study, Physician specialists Physicians play a key role in health care systems by providing a professional medical service. Emerging evidence shows that depression, fatigue, burnout, or emotional exhaustion among physicians might negatively affect physicians' abilities to care for their patients and form sound clinical decisions 1−3) . Furthermore, physicians who are unable to cope with their occupational stress are at a relatively high risk for substance abuse, relationship problems, and suicide 4) . Physicians who are unwell mentally or physically are less able to coordinate their practice with the broader health care system and thus are more prone to providing suboptimal patient care. Numerous studies have investigated the mental health, on-call hours, work loading, workplace nutrition, or health behaviors of physicians and the associated impact on medical errors 5,6) . The research on physical health of physicians has been limited, and has often focused on mortality analysis 7,8) . Furthermore, these studies have always adopted study methods that rely on self-report, which is affected by recall bias.Cancer is the leading cause of death in many countries. The pathogenesis of cancer involves genetics, environmental toxins, lifestyle, and mental health 9) . Physicians are frequently studied as a population that experiences extremely high stress, burnout, and prolonged working hours that might harm one's health. However, they have sound medical knowledge and have easy access to medical resources. We studied the incidence of cancer among Taiwanese physicians using a nationwide cohort study design. Methods: Data were obtained from the National Health Insurance (NHI) system in Taiwan. The physician cohort contained 22,309 physicians, and each physician was randomly frequency-matched according to age and sex with 4 people from the general population.