Aging trends in skin cancer: A long-term observational study in Japan

To the Editor: Incidence of skin cancer is increasing worldwide, particularly affecting the older population.1 This can be mainly attributed to increased cumulative ultraviolet exposure rather than other risk factors including exposure to ionizing radiation, immunosuppression, and long-term scar inflammation.1-3 The rapidly growing elderly population in Japan has led to an alarming increase in the number of skin cancer patients.4 However, studies comparing aging trends between patients with primary skin cancer and other organ cancers have not been reported.