Some epidemiologic observations on cancer in Hong Kong.

The average incidence by age-group per 100,000 for both sexes and the age-standardized incidence rates for the 10 most common cancers in Hong Kong for 1974 were determined. A comparison between the incidence and death rates for these 10 cancers indicated that a good coverage of the actual incidence has been achieved by the Cancer Registry for cancers of the nasopharynx, bronchus, esophagus, colon, rectum, breast, cervix, and bladder, but it was incomplete for cancers of the liver and stomach. A study of their age-specific incidence curves showed a sharp rise in the curve after age 20-24 in cancers of the nasopharynx and liver (males), after age 25-29 in cancers of the cervix and breast (females), and after age 35-39 for the remaining tumors studied; thus a difference in the period of life at which carcinogenesis was initiated was indicated. Epidemiologic observations on nasopharyngeal, esophageal, hepatocellular, and uterine cervical carcinoma were compared, and it is believed that epidemiology is the key to the solution of the cancer problem in Hong Kong.