Oesophageal cancer in Greenland: selected epidemiological and clinical aspects.

During 1955--1974, forty cases of oesophageal cancer were diagnosed among indigenous Greenlanders. The annual incidence rates per 100,000, age adjusted to the "world" population, were 16.3 for males and 11.8 for females in 1955--1964. The corresponding rates in 1965--1974 were 15.9 for males and 6.7 for females with a male:feamle ratio of 2.4:1. These rates rank among the moderately high rates found in India, Puerto Rico and France and in the black population in the US. Age distribution, anatomical location and prognosis followed the normal pattern for oesophageal cancer disease. No particular occupational trend was apparent and there was no difference between towns and settlements. However, a statistically significant geographical gradient of frequency was found with higher rates in the southernmost 3 districts. The traditional Greenland diet may contain concentrations of precursors sufficient to create carcinogenic levels of nitrosamines. Further studies are needed in particular of environmental factors such as foodstuffs, homebrewed beer, drinking water and cigarette smoking. Attention should be focused on the special ecological conditions in southern Greenland.