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Objectives: To determine and compare the incidence of cancer among the 8 Arctic States and their northern regions, with special focus on 3 cross-national indigenous groups – Inuit, Athabaskan Indians and Sami. Methods: Data were extracted from national and regional statistical agencies and cancer registries, with direct age-standardization of rates to the world standard population. For comparison, the “world average” rates as reported in the GLOBOCAN database were used. Findings: Age-standardized incidence rates by cancer sites were computed for the 8 Arctic States and 20 of their northern regions, averaged over the decade 2000–2009. Cancer of the lung and colon/rectum in both sexes are the commonest in most populations. We combined the Inuit from Alaska, Northwest Territories, Nunavut and Greenland into a “Circumpolar Inuit” group and tracked cancer trends over four 5-year periods from 1989 to 2008. There has been marked increase in lung, colorectal and female breast cancers, while cervical cancer has declined. Compared to the GLOBOCAN world average, Inuit are at extreme high risk for lung and colorectal cancer, and also certain rare cancers such as nasopharyngeal cancer. Athabaskans (from Alaska and Northwest Territories) share some similarities with the Inuit but they are at higher risk for prostate and breast cancer relative to the world average. Among the Sami, published data from 3 cohorts in Norway, Sweden and Finland show generally lower risk of cancer than non-Sami. Conclusions: Cancer among certain indigenous people in the Arctic is an increasing public health concern, especially lung and colorectal cancer.

Background. Human papillomavirus (HPV) vaccine prevents cervical pre-cancers and cancers caused by HPV types 16 and 18. This study provides information on the HPV types detected in cervical cancers of Alaska Native (AN) women. Methods. Cases of invasive cervical cancer diagnosed in AN women aged 18 and above between 1980 and 2007 were identified from the Alaska Native Tumor Registry. A representative formalin-fixed, paraffin-embedded archived pathology block was retrieved and serially sectioned to allow histologic confirmation of lesion (first and last sections) and PCR testing of intervening sections. Extracted DNA was tested for HPV using Linear Array HPV Genotyping Test (Roche Diagnostics) with additional INNO-LiPA HPV Genotyping Assay (Innogenetics) testing on negative or inadequate specimens. All specimens were tested for a minimum 37 HPV types. Results. Of 62 cervical cancer specimens evaluated, 57 (91.9%) contained one or more HPV types. Thirty-eight (61.2%) cancers contained HPV types 16 or 18, and 18 (29%) contained an oncogenic type other than type 16 or 18. Conclusions. Overall, almost two-thirds (61.2%) of the archived cervical cancers had detectible HPV types 16 or 18, a finding similar to studies of US women. As expected, a proportion of cancers would not be prevented by the current vaccines. HPV vaccination and cervical cancer screening are important prevention strategies for AN women.

Objectives: To describe the occurrence of pancreatic, biliary tract, and gallbladder cancers within the Alaska Native (AN) population. Study design: Population-based analysis utilizing a tumor registry and comparative population data. Methods: Pancreaticobiliary cancers rates for AN people during 1973–2007 were determined from the Surveillance, Epidemiology, and End Results (SEER) AN Tumor Registry. Cancer incidence rates were age-adjusted to the World Standard Million and compared over 2 time periods with US white and black rates. Results: During 1973–2007, 213 AN people developed pancreatic cancer, 73 gallbladder cancer and 61 biliary tract cancer. Pancreatic cancer occurs at similar rates in AN men and women, but data for 1993–2007 indicate that the rates among AN men may be increasing. The incidence rate in AN women (9.5/100,000) was statistically higher than in US white women (5.8/100,000). The incidence for biliary tract cancer in AN men and gallbladder cancer in AN men and women is statistically higher than that for US whites and blacks. Conclusions: Pancreaticobiliary cancers, particularly biliary tract and gallbladder cancers, in both AN men and women and pancreatic cancer in women occur at an increased rate in AN people. Risk factors relating to the elevated rate are discussed. Certain factors are potentially modifiable, such as the use of tobacco and obesity.