Cancer incidence in Alaska natives.

A survey of cancer incidence among Alaska Natives for the 5-year period 1969-73 revealed fewer cancer cases overall than expected in relation to US rates, but significantly increased risk for certain cancer sites: the nasopharynx in both sexes (with excesses over 15-fold), the liver in males, and the salivary glands, gallbladder, kidney and thyroid in females. Compared with earlier reports, the observations suggest marked changes in cancer incidence among Alaska Natives over the past two decades, with declines in esophageal and invasive cervical cancers, and increases in cancers of the lung, colon and rectum.