Epidemiology of nasopharyngeal and salivary gland carcinoma in Greenland.

From 1950 to 1989 one hundred and forty-four cases of either undifferentiated nasopharyngeal carcinoma (NPC) or salivary gland carcinoma (SGC) were diagnosed in Greenlanders, all born in Greenland. The Greenland SGC is an anaplastic carcinoma with histopathology and electronmicroscopic cytopathological alterations as found in undifferentiated NPC. Both NPC and SGC from Greenland and Alaska are associated with Epstein-Barr virus infection. The incidence rate of NPC based on newly diagnosed cases during the last 15 years is 12.7 for men and 9.2 for women. The same figures for anaplastic SGC are 3.4 and 3.1. These are among the highest incidence rates of Epstein-Barr virus associated carcinomas on record. From 1950 to 1989 there has been an increase in the rate of NPC. From the cumulated rate, it can be predicted that the number of cases will continue to increase during the years to come. During the ten year period 1980 to 1989 patients were questioned about their childhood life style and the family history was taken. The Inuit lifestyle is quite different from that of Europeans and Chinese, but in common with Chinese from Guangzhou (formerly Canton) Greenlanders have a high consumption of fish, fresh as well as dried. Familial clustering has been rarely reported, but in the present investigation 27% of the patients diagnosed between 1980 and 1990 had a positive familial history with one or more confirmed cases among first degree relatives.(ABSTRACT TRUNCATED AT 250 WORDS)