Cancer patterns in Inuit populations

Examining structural factors influencing cancer care experienced by Inuit in Canada: a scoping review

Inuit face worse cancer survival rates and outcomes than the general Canadian population. Persistent health disparities cannot be understood without examining the structural factors that create inequities and continue to impact the health and well-being of Inuit. This scoping review aims to synthesise the available published and grey literature on the structural factors that influence cancer care experienced by Inuit in Canada. Guided by Inuit input from Pauktuutit Inuit Women of Canada as well as the Joanna Briggs Institute scoping review methodology, a comprehensive electronic search along with hand-searching of grey literature and relevant journals was conducted. A total of 30 papers were included for analysis and assessment of relevance. Findings were organised into five categories as defined in the a priori framework related to colonisation, as well as health systems, social, economic, and political structures. The study results highlight interconnections between racism and colonialism, the lack of health service information on urban Inuit, as well as the need for system-wide efforts to address the structural barriers in cancer care.

Food System Transformation and Gut Microbiota Transition: Evidence on Advancing Obesity, Cardiovascular Diseases, and Cancers-A Narrative Review

Food, a vital component of our daily life, is fundamental to our health and well-being, and the knowledge and practices relating to food have been passed down from countless generations of ancestors. Systems may be used to describe this extremely extensive and varied body of agricultural and gastronomic knowledge that has been gathered via evolutionary processes. The gut microbiota also underwent changes as the food system did, and these alterations had a variety of effects on human health. In recent decades, the gut microbiome has gained attention due to its health benefits as well as its pathological effects on human health. Many studies have shown that a person's gut microbiota partially determines the nutritional value of food and that diet, in turn, shapes both the microbiota and the microbiome. The current narrative review aims to explain how changes in the food system over time affect the makeup and evolution of the gut microbiota, advancing obesity, cardiovascular disease (CVD), and cancer. After a brief discussion of the food system's variety and the gut microbiota's functions, we concentrate on the relationship between the evolution of food system transformation and gut microbiota system transition linked to the increase of non-communicable diseases (NCDs). Finally, we also describe sustainable food system transformation strategies to ensure healthy microbiota composition recovery and maintain the host gut barrier and immune functions to reverse advancing NCDs.

The double face of cold in cancer

In a recent paper published in Nature, multiple evidence is provided that cold exposure causes tumor growth restriction in mice, by activating brown adipose tissue metabolism and by subsequent cancer cells' glucose starvation. The paper shows a tumor growth inhibition by 80% for multiple cancer types in mice exposed to 4 °C in comparison with mice exposed to 30 °C. These results are very promising since cost effective protocols could be designed for future clinical trials, for several cancer forms. In this commentary, an extensive analysis is performed on the potential of these results. Some previous published studies are discussed as well, showing differences in tumor growth for mice housed in different external temperatures.

Mutation of KRAS in colorectal adenocarcinoma in Greenland

KRAS mutation is one of the most frequent driver mutations in colorectal cancer (CRC) and is also a prognostic biomarker. The aim of the present study was to determine the frequency of KRAS mutations over time in the Greenlandic population diagnosed with CRC. In total, 578 patients with the diagnosis of adenocarcinoma between 1988 and 2017 were identified. The status of KRAS and the mutational subtypes of KRAS mutations were determined in 102 representative samples by the Idylla™ platform in the time periods 1988-1990, 2002-2004, and 2015-2017. The results showed that the frequency of the KRAS mutations increased significantly, from 27% in 1988-1990 to 43% in 2015-2017 (p < 0.001). Furthermore, the most frequent subtypes of KRAS mutations in Greenland were G12D (c.35G > A) with 14%, G12V (c.35G > T) with 7%, and G13D (c.38G > A) with 6%. In conclusion, this study showed that the frequency of KRAS mutations in CRC has been increasing in recent decades in the specific population of Greenland. The results of this study may be used in initiatives related to targeted therapy of CRC in specific ethnicities and in investigations focusing on the environmental factors of cancer-related somatic mutations.

Histologic and Genotypic Characterization of Lung Cancer in the Inuit Population of the Eastern Canadian Arctic

Inuit are the Indigenous Arctic peoples and residents of the Canadian territory of Nunavut who have the highest global rate of lung cancer. Given lung cancer’s mortality, histological and genomic characterization was undertaken to better understand the disease biology. We retrospectively studied all Inuit cases from Nunavut’s Qikiqtani (Baffin) region, referred to the Ottawa Hospital Cancer Center between 2001 and 2011. Demographics were compiled from medical records and tumor samples underwent pathologic/histologic confirmation. Tumors were analyzed by next generation sequencing (NGS) with a cancer hotspot mutation panel. Of 98 patients, the median age was 66 years and 61% were male. Tobacco use was reported in 87%, and 69% had a history of lung disease (tuberculosis or other). Histological types were: non-small cell lung carcinoma (NSCLC), 81%; small cell lung carcinoma, 16%. Squamous cell carcinoma (SCC) represented 65% of NSCLC. NGS on 55 samples demonstrated mutation rates similar to public lung cancer datasets. In SCC, the STK11 F354L mutation was observed at higher frequency than previously reported. This is the first study to characterize the histologic/genomic profiles of lung cancer in this population. A high incidence of SCC, and an elevated rate of STK11 mutations distinguishes this group from the North American population.

Breast cancer in Indigenous women living in Canada: a scoping review protocol

OBJECTIVE

The objective of this review is to describe and synthesize the current state of knowledge pertaining to breast cancer in Indigenous women living in Canada. We will examine the continuum of breast cancer care in this population, including breast cancer screening, diagnosis, treatment, and surveillance.

INTRODUCTION

Breast cancer in Indigenous women is an evolving health care concern in Canada, with mounting evidence suggesting that these women present at later stages, and have poorer survival rates compared with the general population. A comprehensive overview of the state of knowledge of breast cancer in this population is required.

INCLUSION CRITERIA

The population of interest will include Indigenous women living in Canada aged 18 years or older who have been screened or require screening for breast cancer, or who have been diagnosed with breast cancer. "Indigenous" will include women who identify as First Nations, Métis, or Inuit. Eligible sources must report on breast cancer risk factors, tumor characteristics, health systems access, screening, diagnosis, treatment, surveillance, or breast cancer outcomes. We will include analytic studies, surveys, case series, reviews, meta-analyses, and gray literature.

METHODS

We will conduct a search of five health sciences databases for relevant studies published in English or French from database inception onward. We will utilize dual independent screening for titles, abstracts, and full-text articles, and will utilize a similar method for gray literature sources. Data will be synthesized using a narrative approach, and outcomes of interest will be compared with data from the general breast cancer population.

REGISTRATION

Open Science Framework https://osf.io/xkde5.

Understanding culturally safe cancer survivorship care with inuit in an urban community

Cancer is a leading cause of death among Inuit. A legacy of colonialism, residential schools, and systemic racism has eroded trust among Inuit and many do not receive culturally safe care. This study aimed to explore the meaning of culturally safe cancer survivorship care for Inuit, and barriers and facilitators to receiving it in an urban setting in Ontario Canada. As Inuit and Western researchers, we conducted a descriptive qualitative study. We held two focus groups (n = 27) with cancer survivors and family members, and semi-structured interviews (n = 7) with health providers. Data were analysed using thematic content analysis.Three broad themes emerged as central to culturally safe care: access to traditional ways of life, communication, and family involvement. Family support, patient navigators, and designated spaces were facilitators; lack of support for traditional ways, like country food, was a barrier. Participants were clear what constituted culturally safe care, but major barriers exist. Lack of direction at institutional and governmental levels contributes to the complexity of issues that prevent Inuit from engaging in and receiving culturally safe cancer care. To understand how to transform healthcare to be culturally safe, studies underpinned by Inuit epistemology, values, and principles are required.

Polyunsaturated Fatty Acids Mediated Regulation of Membrane Biochemistry and Tumor Cell Membrane Integrity

Particular dramatic macromolecule proteins are responsible for various cellular events in our body system. Lipids have recently recognized a lot more attention of scientists for understanding the relationship between lipid and cellular function and human health However, a biological membrane is formed with a lipid bilayer, which is called a P-L-P design. Our body system is balanced through various communicative signaling pathways derived from biological membrane proteins and lipids. In the case of any fatal disease such as cancer, the biological membrane compositions are altered. To repair the biological membrane composition and prevent cancer, dietary fatty acids, such as omega-3 polyunsaturated fatty acids, are essential in human health but are not directly synthesized in our body system. In this review, we will discuss the alteration of the biological membrane composition in breast cancer. We will highlight the role of dietary fatty acids in altering cellular composition in the P-L-P bilayer. We will also address the importance of omega-3 polyunsaturated fatty acids to regulate the membrane fluidity of cancer cells.

Cancers as rare diseases: Terminological, theoretical, and methodological biases

OBJECTIVE

Was cancer a rare disease in the past? Our objective is to consider the various terminological, theoretical, and methodological biases that may affect perceptions of the rarity of cancer in the past.

MATERIALS AND METHODS

We discuss relevant malignant neoplastic biomedical and paleopathological literature and evaluate skeletal data. We selected 108 archaeological sites (n = 151 cancer cases) with published malignant neoplasms and that were amenable to calculating cancer crude prevalence. Furthermore, datasets from four medieval/postmedieval Portuguese and 12 postmedieval UK sites were used to compare age-adjusted rates for metastatic bone disease and tuberculosis.

RESULTS

In the literature review, mean cancer crude prevalence (1.2 %; 95 % CI = 0.96-1.4) exceeded the threshold for a rare disease (RD). Age-standardized rates of MBD and TB were not markedly different in the sites surveyed.

CONCLUSIONS

Methodological, theoretical and historical factors contribute to assumptions that cancers were rare diseases. The assumption that cancers are extremely rare in the paleopathological literature was not fully supported. Cancer is a heterogeneous concept, and it is important to view it as such. If a disease is considered rare, we may fail to recognize it or dismiss it as unimportant in the past.

SIGNIFICANCE

We present a re-evaluation of the idea that cancer is a rare disease. We present a more nuanced way of comparing rates of pathological conditions in archaeological contexts.

LIMITATIONS

Variation in the amount of useable information in published literature on malignant neoplasms.

SUGGESTIONS FOR FURTHER RESEARCH

More large-scale studies of cancer in the past alongside comparative studies of cancer prevalence with other assumed rare diseases.

Impact of colorectal cancer screening participation in remote northern Canada: A retrospective cohort study

BACKGROUND

Screening provides earlier colorectal cancer (CRC) detection and improves outcomes. It remains poorly understood if these benefits are realized with screening guidelines in remote northern populations of Canada where CRC rates are nearly twice the national average and access to colonoscopy is limited.

AIM

To evaluate the participation and impact of CRC screening guidelines in a remote northern population.

METHODS

This retrospective cohort study included residents of the Northwest Territories, a northern region of Canada, age 50-74 who underwent CRC screening by a fecal immunohistochemical test (FIT) between January 1, 2014 to March 30, 2019. To assess impact, individuals with a screen-detected CRC were compared to clinically-detected CRC cases for stage and location of CRC between 2014-2016. To assess participation, we conducted subgroup analyses of FIT positive individuals exploring the relationships between signs and symptoms of CRC at the time of screening, wait-times for colonoscopy, and screening outcomes. Two sample Welch t-test was used for normally distributed continuous variables, Mann-Whitney-Wilcoxon Tests for data without normal distribution, and Chi-square goodness of fit test for categorical variables. A P value of < 0.05 was considered to be statistically significant.

RESULTS

6817 fecal tests were completed, meaning an annual average screening rate of 25.04%, 843 (12.37%) were positive, 629 individuals underwent a follow-up colonoscopy, of which, 24.48% had advanced neoplasia (AN), 5.41% had CRC. There were no significant differences in stage, pathology, or location between screen-detected cancers and clinically-detected cancers. In assessing participation and screening outcomes, we observed 49.51% of individuals referred for colonoscopy after FIT were ineligible for CRC screening, most often due to signs and symptoms of CRC. Individuals were more likely to have AN if they had signs and symptoms of cancer at the time of screening, waited over 180 d for colonoscopy, or were indigenous [respectively, estimated RR 1.18 95%CI of RR (0.89-1.59)]; RR 1.523 (CI: 1.035, 2.240); RR 1.722 (CI: 1.165, 2.547)].

CONCLUSION

Screening did not facilitate early cancer detection but facilitated higher than anticipated AN detection. Signs and symptoms of CRC at screening, and long colonoscopy wait-times appear contributory.

CPT1A-mediated Fat Oxidation, Mechanisms, and Therapeutic Potential

Energy homeostasis during fasting or prolonged exercise depends on mitochondrial fatty acid oxidation (FAO). This pathway is crucial in many tissues with high energy demand and its disruption results in inborn FAO deficiencies. More than 15 FAO genetic defects have been currently described, and pathological variants described in circumpolar populations provide insights into its critical role in metabolism. The use of fatty acids as energy requires more than 2 dozen enzymes and transport proteins, which are involved in the activation and transport of fatty acids into the mitochondria. As the key rate-limiting enzyme of FAO, carnitine palmitoyltransferase I (CPT1) regulates FAO and facilitates adaptation to the environment, both in health and in disease, including cancer. The CPT1 family of proteins contains 3 isoforms: CPT1A, CPT1B, and CPT1C. This review focuses on CPT1A, the liver isoform that catalyzes the rate-limiting step of converting acyl-coenzyme As into acyl-carnitines, which can then cross membranes to get into the mitochondria. The regulation of CPT1A is complex and has several layers that involve genetic, epigenetic, physiological, and nutritional modulators. It is ubiquitously expressed in the body and associated with dire consequences linked with genetic mutations, metabolic disorders, and cancers. This makes CPT1A an attractive target for therapeutic interventions. This review discusses our current understanding of CPT1A expression, its role in heath and disease, and the potential for therapeutic opportunities targeting this enzyme.

North Pacific Baleen Whales as a Potential Source of Persistent Organic Pollutants (POPs) in the Diet of the Indigenous Peoples of the Eastern Arctic Coasts

Among marine mammals, gray and bowhead whales contain large amounts of fat and thereby constitute crucial dietary components of the traditional diet of indigenous peoples of the Eastern Arctic. Despite the high nutritional and cultural value of gray and bowhead whales, there is a risk of persistent organic pollutant (POP) intake by indigenous individuals who use marine mammals as their main source of fat. POPs are lipophilic pollutants and are known to accumulate and magnify along the marine food web. Consumption of foods contaminated by POPs can perturb the endocrine, reproductive, and immune systems, and can potentially cause cancer. Moderate to relatively high concentrations of POPs have indeed been reported in the edible tissues of gray and bowhead whales consumed by indigenous peoples of the North Pacific Ocean. Even though their consumption is potentially harmful, there is no regular monitoring of eco-toxicants in the foods consumed by the indigenous peoples of the Eastern Arctic. In our view, the routine analyses of consumable parts of whales and of comparable nutritional items need to be included in the Russian Arctic Biomonitoring Programme.

Can postfertile life stages evolve as an anticancer mechanism?

Why a postfertile stage has evolved in females of some species has puzzled evolutionary biologists for over 50 years. We propose that existing adaptive explanations have underestimated in their formulation an important parameter operating both at the specific and the individual levels: the balance between cancer risks and cancer defenses. During their life, most multicellular organisms naturally accumulate oncogenic processes in their body. In parallel, reproduction, notably the pregnancy process in mammals, exacerbates the progression of existing tumors in females. When, for various ecological or evolutionary reasons, anticancer defenses are too weak, given cancer risk, older females could not pursue their reproduction without triggering fatal metastatic cancers, nor even maintain a normal reproductive physiology if the latter also promotes the growth of existing oncogenic processes, e.g., hormone-dependent malignancies. At least until stronger anticancer defenses are selected for in these species, females could achieve higher inclusive fitness by ceasing their reproduction and/or going through menopause (assuming that these traits are easier to select than anticancer defenses), thereby limiting the risk of premature death due to metastatic cancers. Because relatively few species experience such an evolutionary mismatch between anticancer defenses and cancer risks, the evolution of prolonged life after reproduction could also be a rare, potentially transient, anticancer adaptation in the animal kingdom.

Access to radiotherapy among circumpolar Inuit populations

Cancer is a substantial health burden for Inuit populations, an Indigenous peoples who primarily inhabit the circumpolar regions of Alaska, Canada, Greenland, and Russia. Access to radiotherapy is lacking or absent in many of these regions, despite it being an essential component of cancer treatment. This Review presents an overview of factors influencing radiotherapy delivery in each of the four circumpolar Inuit regions, which include population and geography, health-systems infrastructure, and cancer epidemiology. This Review also provides insight into the complex patient pathways needed to access radiotherapy, and on radiotherapy use. The unique challenges in delivering radiotherapy to circumpolar Inuit populations are discussed, which, notably, include geographical and cultural barriers. Recommendations include models of care that have successfully addressed these barriers, and highlight the need for increased collaboration between circumpolar referral centres in Alaska, Canada, Greenland, and Russia to ultimately allow for better delivery of cancer treatment.

Time to Diagnosis and Treatment with Palliative Radiotherapy among Inuit Patients with Cancer from the Arctic Territory of Nunavut, Canada

AIMS

The cancer burden among Circumpolar Inuit is high. Palliative radiotherapy is a mainstay treatment for controlling symptoms of advanced cancers, but Inuit are required to travel far distances to access this service. Access to palliative radiotherapy and time away from home communities have not been explored among this population. We sought to describe the time intervals from symptom onset to the start of palliative radiotherapy among Canadian Inuit patients treated at The Ottawa Hospital (TOH).

MATERIALS AND METHODS

A retrospective review of Inuit patients from Nunavut treated with radiotherapy between 2005 and 2014 at TOH.

RESULTS

Of a total of 152 radiotherapy patients, 88 (58%) were treated palliatively. Of these, 61 (70%) had stage IV disease at diagnosis and 63 (72%) had lung cancer. The median time from referral for specialist care to the patient's first flight to Ottawa was 4 days (range 0-97). The median length of treatment was 7 days (range 0-27), but patients spent a median of 64.5 days (range 14-633) in Ottawa. The median survival from the date of pathological diagnosis was 5.2 months.

CONCLUSIONS

Most Inuit radiotherapy patients at TOH were treated palliatively. Patients were brought from Nunavut relatively quickly for specialist care, which is encouraging. However, patients spent over 2 months away from home, in the context of a median survival of less than 6 months. Opportunities for improvement include both provider and system-level changes, which may be applicable to other Circumpolar Inuit regions across Europe and North America.

Lipid Metabolism and Endocrine Resistance in Prostate Cancer, and New Opportunities for Therapy

Prostate cancer (PCa) is the most common cancer in men, and more than 10% of men will be diagnosed with PCa during their lifetime. Patients that are not cured with surgery or radiation are largely treated with endocrine therapies that target androgens or the androgen receptor (AR), a major driver of PCa. In response to androgen deprivation, most PCas progress to castrate resistant PCa, which is treated with anti-androgens like enzalutamide, but tumors still progress and become incurable. Thus, there is a critical need to identify cellular pathways that allow tumors to escape anti-androgen therapies. Epidemiological studies suggest that high-fat diets play important roles in PCa progression. Lipid metabolism rewires the PCa metabolome to support growth and resistance to endocrine therapies, although the exact mechanisms remain obscure. Therapeutic effects have been observed inhibiting several aspects of PCa lipid metabolism: Synthesis, uptake, and oxidation. Since AR remains a driver of PCa in advanced disease, strategies targeting both lipid metabolism and AR are starting to emerge, providing new opportunities to re-sensitize tumors to endocrine therapies with lipid metabolic approaches.

Improved survival of head and neck cancer patients in Greenland

Previously, head and neck cancer (HNC) patients in Greenland have had significant diagnostic delay and poor survival rates. From 2005-2009 several initiatives have been made to ensure faster diagnosis and better survival. The aim of this study was to compare the prognosis before and after these initiatives were introduced.

All Greenlandic patients diagnosed with HNC between 2005 and 2012 were included. Data were retrieved from medical records and national databases and compared with the period 1994-2003.

A total of 98 patients were identified. Diagnostic delay was significantly lower compared to the period 1994–2004 (p=0.048). The 3-year overall survival was 56% for all HNC and 47% for nasopharyngeal carcinomas. We found that patients with HNC between 1994 and 2003 had a higher risk of death from all reasons compared with the period 2005–2012 (HR 2.17; CI 1.46–3.23) after adjustments for stage and diagnostic delay.

Patients with head HNC in Greenland from 2005-2012 were diagnosed earlier and had a better overall survival compared to the period 1994–2003. The change in survival is more likely to be due to improvement in treatment rather than the initiated interventions. Although survival has improved in Greenland, demographic problems and lack of specialists remain a challenge.

Combination of 247 Genome-Wide Association Studies Reveals High Cancer Risk as a Result of Evolutionary Adaptation

Analysis of GLOBOCAN-2012 data shows clearly here that cancer incidence worldwide is highly related with low average annual temperatures and extreme low temperatures. This applies for all cancers together or separately for many frequent or rare cancer types (all cancers P = 9.49×10-18). Supporting fact is that Inuit people, living at extreme low temperatures, have the highest cancer rates today. Hypothesizing an evolutionary explanation, 240 cancer genome-wide association studies, and seven genome-wide association studies for cold and high-altitude adaptation were combined. A list of 1,377 cancer-associated genes was created to initially investigate whether cold selected genes are enriched with cancer-associated genes. Among Native Americans, Inuit and Eskimos, the highest association was observed for Native Americans (P = 6.7×10-5). An overall or a meta-analysis approach confirmed further this result. Similar approach for three populations living at extreme high altitude, revealed high association for Andeans-Tibetans (P = 1.3×10-11). Overall analysis or a meta-analysis was also significant. A separate analysis showed special selection for tumor suppressor genes. These results can be viewed along with those of previous functional studies that showed that reduced apoptosis potential due to specific p53 variants (the most important tumor suppressor gene) is beneficial in high-altitude and cold environments. In conclusion, this study shows that genetic variants selected for adaptation at extreme environmental conditions can increase cancer risk later on age. This is in accordance with antagonistic pleiotropy hypothesis.

The Phylogeographic Diversity of EBV and Admixed Ancestry in the Americas⁻Another Model of Disrupted Human-Pathogen Co-Evolution

Epstein-Barr virus (EBV) is an etiological agent for gastric cancer with significant worldwide variations. Molecular characterizations of EBV have shown phylogeographical variations among healthy populations and in EBV-associated diseases, particularly the cosegregated BamHI-I fragment and XhoI restriction site of exon 1 of the LMP-1 gene. In the Americas, both cosegregated variants are present in EBV carriers, which aligns with the history of Asian and European human migration to this continent. Furthermore, novel recombinant variants have been found, reflecting the genetic makeup of this continent. However, in the case of EBV-associated gastric cancer (EBV-associated GC), the cosegregated European BamHI-“i” fragment and XhoI restriction site strain prevails. Thus, we propose that a disrupted coevolution between viral phylogeographical strains and mixed human ancestry in the Americas might explain the high prevalence of this particular gastric cancer subtype. This cosegregated region contains two relevant transcripts for EBV-associated GC, the BARF-1 and miR-BARTs. Thus, genome-wide association studies (GWAS) or targeted sequencing of both transcripts may be required to clarify their role as a potential source of this disrupted coevolution.

Urban environment and cancer in wildlife: available evidence and future research avenues

While it is generally known that the risk of several cancers in humans is higher in urban areas compared with rural areas, cancer is often deemed a problem of human societies with modern lifestyles. At the same time, more and more wild animals are affected by urbanization processes and are faced with the need to adapt or acclimate to urban conditions. These include, among other things, increased exposure to an assortment of pollutants (e.g. chemicals, light and noise), novel types of food and new infections. According to the abundant literature available for humans, all of these factors are associated with an increased probability of developing cancerous neoplasias; however, the link between the urban environment and cancer in wildlife has not been discussed in the scientific literature. Here, we describe the available evidence linking environmental changes resulting from urbanization to cancer-related physiological changes in wild animals. We identify the knowledge gaps in this field and suggest future research avenues, with the ultimate aim of understanding how our modern lifestyle affects cancer prevalence in urbanizing wild populations. In addition, we consider the possibilities of using urban wild animal populations as models to study the association between environmental factors and cancer epidemics in humans, as well as to understand the evolution of cancer and defence mechanisms against it.

Oncological treatment and outcome of colorectal cancer in Greenland

Oncological treatment of colorectal cancer (CRC) has been available in Greenland since 2004. Treatment is provided by Queen Ingrid´s Hospital (QIH), under supervision from the Department of Oncology, Rigshospitalet, Denmark. The study describes patient characteristics, oncological treatment and survival for the first 8 years of treatment. The study was a registry-based observational study of all patients in Greenland diagnosed with histologically verified CRC from August 2004 to August 2012. Analyses were stratified according to stage and discussed in relation to reported data from patients with CRC in Denmark. 180 patients were included. . Stage I, II, III, and IV comprised 15, 34, 23, and 23%, respectively. 5% presented with unknown stage. A total of 51% received oncological treatment. 79% of patients with Stage III disease received adjuvant chemotherapy, 61% of patients with metastatic CRC received palliative chemotherapy. Five-year survival was 48 and 53% for colon and rectum cancer, respectively. An insignificant trend towards higher survival in men than in women was seen; adjusted hazard ratio for death (women vs men) = 1.46 (95% CI = 0.97-2.19). In conclusion; Stage distribution, provision of oncological treatment and 5-year survival were comparable to patients diagnosed and treated in Denmark.

Cancer Incidence and Mortality in Greenland 1983-2014 - Including Comparison With the Other Nordic Countries

BACKGROUND

During the last decades, social and life-style changes in Greenland have led to an increase in the incidence of several non-communicable diseases. Our aim is to present the cancer incidence and mortality in Greenland and compare the results with the other Nordic countries.

METHODS

The data stems from The Danish Cancer Registry and The Danish Register of Causes of Death. Comparable data on cancer incidence and mortality in Denmark, Finland, Iceland, Norway, Sweden, and Greenland are available through collaboration between Nordic Cancer Registries (NORDCAN). We included all individuals residing in Greenland and diagnosed with or died of a cancer from 1983 to 2014.

FINDINGS

The total number of cancer cases in Greenland for the study period was 4716 and there were 3231 cancer deaths. Respiratory and gastrointestinal cancers had the highest incidence as well as mortality in Greenland for the entire time period and for both sexes. Compared to the other Nordic countries, Greenland had significantly higher incidence and mortality rates for several cancers. Cancer of the lip, oral cavity, and pharynx, respiratory cancer, and cancer of unknown sites had the highest incidence rate ratios (2.3-3.9) and mortality rate ratios (2.7-9.9) for both sexes. The time trend from 1983 to 2014 showed a significant increase in cancer incidence in Greenland with nearly the same incidence level as the other Nordic countries. While the cancer mortality decreased in the other Nordic countries during the time period studied, there was no change in the cancer-specific mortality in Greenland.

INTERPRETATIONS

The trends in cancer incidence and mortality in Greenland compared to the other Nordic countries have not been reported earlier. These data underline a need to focus on cancer-specific mortality in Greenland and prevention of high-incidence cancers related to well-established risk factors.

Food in rural northern Norway in relation to Sami ethnicity: the SAMINOR 2 Clinical Survey

OBJECTIVE

To estimate current food intake in the population of northern Norway and to investigate the impact of self-perceived Sami ethnicity and region of residence on food intake.

DESIGN

The data are part of the second cross-sectional survey of the Population-based Study on Health and Living Conditions in Regions with Sami and Norwegian Populations (the SAMINOR 2 Clinical Survey, 2012-2014). Food intake was assessed by an FFQ. Ethnic and regional differences in food intake were studied by sex-specific, multivariable-adjusted quantile regression models.

SETTING

Ten municipalities (rural northern Norway).

SUBJECTS

Males (n 2054) and females (n 2450) aged 40-69 years (2743 non-Sami, 622 multi-ethnic Sami, 1139 Sami).

RESULTS

The diet of Sami participants contained more reindeer meat, moose meat, food made with animal blood and freshwater fish; and contained less lean fish and vegetables. In the inland region, the consumption of reindeer meat was greatest in Sami participants, followed by multi-ethnic Sami participants and non-Sami participants, who had the lowest consumption (median 25, 12 and 8 g/d, respectively). Compared with the inland region, fish roe/liver intake was higher in the coastal region and lean fish intake was twice as high (41 and 32 g/d in males and females, respectively).

CONCLUSIONS

When compared with non-Sami participants, those with solely self-perceived Sami ethnicity reported a significantly different intake of several foods, especially reindeer meat in the inland region. Multi-ethnic Sami tended to have similar diets to non-Sami. Residence in the coastal region predicted higher fish and roe/liver intake.

Androgen Receptor Genotype in Humans and Susceptibility to Endocrine Disruptors

Although animal studies have raised concern that the influence of endocrine-disrupting compounds would obstruct the development of the male reproductive system, in general, exposure levels far above those found in humans have been needed to induce reproductive toxicity in animal models. Human data are inconclusive and have evoked the question whether endocrine-disrupting compounds can have any impact on hormonal function and thus health consequences when natural hormones are present. Indeed, many contaminants with hormone-like activity are much less potent than endogenous hormones themselves: 17β-oestradiol was, for instance, estimated to be 17,000 times more potent than o,p'-DDT. However, humans are exposed to a multitude of agents, and when present in sufficient number and concentration, they might in principle act collected on the actions of endogenous hormones. Whether such effects will be physiologically relevant is still not known. Nevertheless, in the worst-case scenario, there are no threshold levels below which there are no effects at all, and one target molecule is the androgen receptor. This mini review focuses on the androgen receptor gene, its link with classical endocrine disruptors and smoking, and how common genetic variants in the androgen receptor gene may influence physiological outcomes.

Indoor Radon in Micro-geological Setting of an Indigenous Community in Canada: A Pilot Study for Hazard Identification

BACKGROUND

Radon is the second leading cause of lung cancer after smoking. In Canada, the health authorities have no access to comprehensive profile of the communities built over uranium-rich micro-geological settings. The present indoor radon monitoring guideline is unable to provide an accurate identification of health hazards due to discounting several parameters of housing characteristics.

OBJECTIVE

To explore indoor radon levels in a micro-geological setting known for high uranium in bedrock and to develop a theoretical model for a revised radon testing protocol.

METHODS

We surveyed a remote Inuit community in Labrador, located in the midst of uranium belt. We selected 25 houses by convenience sampling and placed electret-ion-chamber radon monitoring devices in the lowest levels of the house (basement/crawl space). The standard radon study questionnaire developed and used by Health Canada was used.

RESULTS

7 (28%) houses had radon levels above the guideline value (range 249 to 574 Bq/m³). Housing characteristics, such as floors, sump holes, ventilation, and heating systems were suspected for high indoor radon levels and health consequences.

CONCLUSION

There is a possibility of the existence of high-risk community in a low-risk region. The regional and provincial health authorities would be benefited by consulting geologists to identify potentially high-risk communities across the country. Placing testing devices in the lowest levels provides more accurate assessment of indoor radon level. The proposed protocol, based on synchronized testing of radon (at the lowest level of houses and in rooms of normal occupancy) and thorough inspection of the houses will be a more effective lung cancer prevention strategy.

Health effects associated with measured levels of contaminants in the Arctic

The Human Health Assessment Group has over the past decade recommended that effect studies be conducted in the circumpolar area. Such studies examine the association between contaminant exposure in the Arctic populations and health effects. Because foetuses and young children are the most vulnerable, effect studies are often prospective child cohort studies. The emphasis in this article is on a description of the effects associated with contaminant exposure in the Arctic. The main topics addressed are neurobehavioural, immunological, reproductive, cardiovascular, endocrine and carcinogenic effect. For each topic, the association between exposure and effects is described, and some results are reported for similar studies outside the Arctic.

Cancer among circumpolar populations: an emerging public health concern

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.

A retrospective review of cancer treatments and outcomes among Inuit referred from Nunavut, Canada

BACKGROUND

Cancer is a health concern in Inuit populations. Unique cultural, dietary, and genetic factors and geographic isolation influence cancer epidemiology in this group. Inuit-specific data about oncology treatments and survival outcomes in Canadian Inuit referred to urban treatment centres are lacking.

METHODS

A retrospective chart review of Inuit patients referred to The Ottawa Hospital Cancer Centre (tohcc) from the Baffin region of Nunavut between 2000 and 2010 was conducted. Nunavut cancer registry data were used to establish the percentage of cancer cases referred and their survival outcomes.

RESULTS

Of 307 cancer patients registered among Baffin-region Inuit, 216 [70% (63 men, 153 women)] were referred to tohcc for chemotherapy (ct) and radiation therapy (rt). Mean age in the referred group was 59.3 years (range: 25-89 years), and current smokers constituted half the group (52%). The cancers most commonly leading to referral in men were lung (55%), colorectal (19%), and nasopharyngeal (11%) cancers; in women, they were lung (46%), colorectal (24%), breast (10%), nasopharyngeal (6%), and cervical (5%) cancers. Of the 216 referred patients, 82 (38%) had already undergone surgery, and 18 (8%) received chemoradiation or rt only, all given with curative intent. Among the surgical patients referred, 33 (40%) and 23 (28%) went on to receive adjuvant ct and adjuvant rt respectively. Among 116 patients referred for palliative care, 64 (55%) received ct, 76 (66%) received rt, 43 (37%) received both ct and rt, and 19 (16%) received neither treatment. Median all-stage overall survival was 10 months for patients with lung cancer [95% confidence interval: 6.1 to 13.9 months] and 37 months for patients with colorectal cancer [95% confidence interval: 14.8 to 59.2 months].

CONCLUSIONS

High uptake of palliative and adjuvant ct and rt was observed in the Inuit patients referred to tohcc. Lung cancer was the most common cancer in referred Inuit men and women. The survival rates for Inuit lung cancer patients referred to tohcc were comparable to those in the rest of Canada. Further research is required to understand reasons for non-referral of Canadian Inuit to tohcc.

Omega-3 fatty acids for breast cancer prevention and survivorship

Women with evidence of high intake ratios of the marine omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) relative to the omega-6 arachidonic acid have been found to have a reduced risk of breast cancer compared with those with low ratios in some but not all case–control and cohort studies. If increasing EPA and DHA relative to arachidonic acid is effective in reducing breast cancer risk, likely mechanisms include reduction in proinflammatory lipid derivatives, inhibition of nuclear factor-κB-induced cytokine production, and decreased growth factor receptor signaling as a result of alteration in membrane lipid rafts. Primary prevention trials with either risk biomarkers or cancer incidence as endpoints are underway but final results of these trials are currently unavailable. EPA and DHA supplementation is also being explored in an effort to help prevent or alleviate common problems after a breast cancer diagnosis, including cardiac and cognitive dysfunction and chemotherapy-induced peripheral neuropathy. The insulin-sensitizing and anabolic properties of EPA and DHA also suggest supplementation studies to determine whether these omega-3 fatty acids might reduce chemotherapy-associated loss of muscle mass and weight gain. We will briefly review relevant omega-3 fatty acid metabolism, and early investigations in breast cancer prevention and survivorship.

Omega-3 fatty acids for breast cancer prevention and survivorship

Women with evidence of high intake ratios of the marine omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) relative to the omega-6 arachidonic acid have been found to have a reduced risk of breast cancer compared with those with low ratios in some but not all case-control and cohort studies. If increasing EPA and DHA relative to arachidonic acid is effective in reducing breast cancer risk, likely mechanisms include reduction in proinflammatory lipid derivatives, inhibition of nuclear factor-κB-induced cytokine production, and decreased growth factor receptor signaling as a result of alteration in membrane lipid rafts. Primary prevention trials with either risk biomarkers or cancer incidence as endpoints are underway but final results of these trials are currently unavailable. EPA and DHA supplementation is also being explored in an effort to help prevent or alleviate common problems after a breast cancer diagnosis, including cardiac and cognitive dysfunction and chemotherapy-induced peripheral neuropathy. The insulin-sensitizing and anabolic properties of EPA and DHA also suggest supplementation studies to determine whether these omega-3 fatty acids might reduce chemotherapy-associated loss of muscle mass and weight gain. We will briefly review relevant omega-3 fatty acid metabolism, and early investigations in breast cancer prevention and survivorship.

Dietary adequacy among rural Yup'ik women in western Alaska

OBJECTIVES

To assess (1) energy and nutrient intake; (2) dietary adequacy; (3) traditional and nontraditional foods consumed; and (4) main foods contributing to energy and selected nutrient intake among Yup'ik women in Western Alaska.

METHODS

Up to 3 24-hour dietary recalls were collected to assess the dietary intake. Dietary adequacy was determined by comparing women's daily nutrient intakes to corresponding dietary reference intakes (DRIs).

RESULTS

Mean daily energy intake for the women was 2172 kcal, exceeding the DRI for energy. The majority of women (90-100%) fell below the recommendations for dietary fiber, calcium, and vitamins D and E. More than 50% of women fell below the recommendations for vitamin A, and more than one third were below the DRI for zinc and vitamins C and B6. Juices/pop (including Tang, Kool-Aid, soda/pop, fruit juice, and energy drink), coffee, and traditional fish were the most frequently reported food items. Sweetened beverages and pop were the main contributors to energy, carbohydrate, and sugar intake. Traditional foods provided 34% of protein, 27% of iron, 23% of vitamin A, and 21% of zinc.

CONCLUSIONS

Among Yup'ik women, juices/pop were the most frequently consumed foods contributing to the high energy intake. However, traditional food still contributes substantially to certain nutrients. These data contribute to an understanding of dietary adequacy in this population and will aid in the development of a nutritional intervention program.

Changing Dietary Patterns in the Canadian Arctic: Frequency of Consumption of Foods and Beverages by Inuit in Three Nunavut Communities

Background

Inuit in Arctic regions are experiencing a rapid diet and lifestyle transition. There are limited data on food consumption patterns among this unique population, raising concerns about assessing the risk for the development of diet-related chronic diseases.

Objective

To assess the current frequency of consumption of foods and beverages among Inuit in Nunavut, Arctic Canada.

Methods

A cross-sectional dietary study was con- ducted among randomly selected Inuit adults from three communities in Nunavut using a validated quantitative food frequency questionnaire. The participants were 175 women and 36 men with median (IQR) ages of 41.0 (32.5–48.5) and 40.1 (30.0–50.0) years, respectively. The mean and median frequencies of consumption over a 30-day period were computed for 147 individual food items and grouped as foods or beverages.

Results

The 30 most frequently consumed foods were identified. Non-nutrient-dense foods (i.e., high-fat and high-sugar foods) were the most frequently consumed food group (median intake, 3.4 times/day), followed by grains (2.0 times/day) and traditional meats (1.7 times/ day). The frequency of consumption of fruits (0.7 times/ day) and vegetables (0.4 times/day) was low. The median values for the three most frequently consumed food items were sugar or honey (once/day), butter (0.71 times/day), and Coffee-mate (0.71 times/day). Apart from water, coffee, and tea, the most frequently consumed beverages were sweetened juices (0.71 times/day) and regular pop (soft drinks) (0.36 times/day). This study showed that non-nutrient-dense foods are consumed most frequently in these Inuit communities.

Conclusions

The results have implications for dietary quality and provide useful information on current die- tary practices to guide nutritional intervention programs.

Traditional food patterns are associated with better diet quality and improved dietary adequacy in Aboriginal peoples in the Northwest Territories, Canada

BACKGROUND

Traditionally, the Arctic diet has been derived entirely from locally harvested animal and plant species; however, in recent decades, imported foods purchased from grocery stores have become widely available. The present study aimed to examine Inuvialuit, traditional or nontraditional dietary patterns; nutrient density of the diet; dietary adequacy; and main food sources of energy and selected nutrient intakes.

METHODS

This cross-sectional study used a culturally appropriate quantitative food frequency questionnaire to assess diet. Traditional and nontraditional eaters were classified as those consuming more or less than 300 g of traditional food daily. Nutrient densities per 4184 kJ (1000 kcal) were determined. Dietary adequacy was determined by comparing participants' nutrient intakes with the Dietary Reference Intakes.

RESULTS

The diet of nontraditional eaters contained, on average, a lower density of protein, niacin, vitamin B12 , iron, selenium, zinc, omega-3 fatty acids (P ≤ 0.0001), vitamin B6 , potassium, thiamin, pantothenic acid (P ≤ 0.001), riboflavin and magnesium (P ≤ 0.05). Inadequate nutrient intake was more common among nontraditional eaters for calcium, folate, vitamin C, zinc, thiamin, pantothenic acid, vitamin K, magnesium, potassium and sodium. Non-nutrient-dense foods (i.e. high fat and high sugar foods) contributed to energy intake in both groups, more so among nontraditional eaters (45% versus 33%). Traditional foods accounted for 3.3% and 20.7% of total energy intake among nontraditional and traditional eaters, respectively.

CONCLUSIONS

Diet quality and dietary adequacy were better among Inuvialuit who consumed more traditional foods. The promotion of traditional foods should be incorporated in dietary interventions for this population.

Trends of cervical cancer in Greenland: a 60-year overview

BACKGROUND

Due to its extraordinarily fast economic and social transition, virtually closed borders before 1940 and, moreover, that 85% of the population has the distinctive genetics of the Inuit, Greenland is a very interesting country to study cervical cancer from a historical perspective. Nevertheless, little has been reported about long-term cancer trends in Greenland. Our aim was to describe and interpret the incidence of cervical cancer from 1950 to 2009.

MATERIAL AND METHODS

We systematically searched PubMed for articles reporting the incidence of cervical cancer in Greenland. We supplemented this with data for 1980-2009 obtained from the Chief Medical Officer of Greenland.

RESULTS

Incidence of cervical cancer was around 10 per 100 000 women (age-standardised, world population, ASW) in the 1950s, 30 per 100 000 in the 1960s, and in the 1980s around 60 per 100 000. From 1985 onwards, the incidence of cervical cancer started decreasing to the current level of 25 per 100 000.

CONCLUSION

The steep increase in the incidence of cervical cancer from the 1950s onwards is unlikely to be explained by increasing completeness of data. In parallel with the economic development, however, out-of-wedlock births (proxy for sexual behaviour) increased dramatically from 1935 onwards while tobacco use increased from the 1950s onwards. From the late 1960s to around 1990, data suggested rather stable but high levels of sexual habits. The decrease in the incidence of cervical cancer since 1985 is consistent with the introduction of screening. The data strongly suggested that the increased burden of cervical cancer in Greenlandic women was real and followed earlier changes in sexual behaviour; these changes were likely a consequence of the tremendous societal changes.

Familial predisposition for salivary gland cancer in Finland

BACKGROUND

Salivary gland cancer (SGC) accounts for 3–5% of head and neck malignancies, and register-based studies estimate the familial proportion to be 0.15%.

OBJECTIVE

We studied familial predisposition for SGC in the genetically distinct Finnish population.

PATIENTS AND METHODS

We sent a patient questionnaire to 161 Finnish SGC patients, 86 of whom responded.

RESULTS

A total of 76% of the patients reported having one or more relatives with cancer, 30% two or more, and 9% three or more but only one patient reported having a relative with SGC. Tracing the birthplaces of the SGC patients’ grandparents showed no regional clustering suggestive of a founder effect.

CONCLUSIONS

Lack of familial SGC patients and the absence of a founder effect strongly suggest that familial predisposition for SGC is insignificant in the Finnish population. Various histological subtypes and the rarity of these neoplasms make it impossible to draw conclusions about site-specific association between SGC and other malignancies.

Polymorphisms in phase I and phase II genes and breast cancer risk and relations to persistent organic pollutant exposure: a case-control study in Inuit women

BACKGROUND

We have previously reported that chemicals belonging to the persistent organic pollutants (POPs) such as perfluorinated compounds (PFAS) and polychlorinated biphenyls (PCBs) are risk factors in Breast Cancer (BC) development in Greenlandic Inuit women. The present case-control study aimed to investigate the main effect of polymorphisms in genes involved in xenobiotic metabolism and estrogen biosynthesis, CYP1A1, CYP1B1, COMT and CYP17, CYP19 and the BRCA1 founder mutation in relation to BC risk and to explore possible interactions between the gene polymorphisms and serum POP levels on BC risk in Greenlandic Inuit women.

METHODS

The study population consisted of 31 BC cases and 115 matched controls, with information on serum levels of POPs. Genotyping was conducted for CYP1A1 (Ile462Val; rs1048943), CYP1B1 (Leu432Val; rs1056836), COMT (Val158Met; rs4680), CYP17A1 (A1> A2; rs743572); CYP19A1 (C> T; rs10046) and CYP19A1 ((TTTA)n repeats) polymorphisms and BRCA1 founder mutation using TaqMan allelic discrimination method and polymerase chain reaction based restriction fragment length polymorphism. The χ2 -test was used to compare categorical variables between cases and controls and the odds ratios were estimated by unconditional logistic regression models.

RESULTS

We found an independent association of CYP1A1 (Val) and CYP17 (A1) with BC risk.Furthermore, an increased BC risk was observed for women with high serum levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) and carriers of at least: one CYP1A1 variant Val allele; one variant COMT Met allele; or the common CYP17 A1 allele. No combined effects were seen between PFAS exposure and CYP1B1 and CYP19 polymorphisms. The risk of BC was not found significantly associated with exposure to PCBs and OCPs, regardless of genotype for all investigated SNPs. The frequency of the Greenlandic founder mutation in BRCA1 was as expected higher in cases than in controls.

CONCLUSIONS

The BRCA1 founder mutation and polymorphisms in CYP1A1 (Val) and CYP17 (A1) can increase the BC risk among Inuit women and the risk increases with higher serum levels of PFOS and PFOA. Serum PFAS levels were a consistent risk factor of BC, but inter-individual polymorphic differences might cause variations in sensitivity to the PFAS/POP exposure.

The burden of stomach cancer in indigenous populations: a systematic review and global assessment

OBJECTIVE

Stomach cancer is a leading cause of cancer death, especially in developing countries. Incidence has been associated with poverty and is also reported to disproportionately affect indigenous peoples, many of whom live in poor socioeconomic circumstances and experience lower standards of health. In this comprehensive assessment, we explore the burden of stomach cancer among indigenous peoples globally.

DESIGN

The literature was searched systematically for studies on stomach cancer incidence, mortality and survival in indigenous populations, including Indigenous Australians, Maori in New Zealand, indigenous peoples from the circumpolar region, native Americans and Alaska natives in the USA, and the Mapuche peoples in Chile. Data from the New Zealand Health Information Service and the Surveillance Epidemiology and End Results (SEER) Program were used to estimate trends in incidence.

RESULTS

Elevated rates of stomach cancer incidence and mortality were found in almost all indigenous peoples relative to corresponding non-indigenous populations in the same regions or countries. This was particularly evident among Inuit residing in the circumpolar region (standardised incidence ratios (SIR) males: 3.9, females: 3.6) and in Maori (SIR males: 2.2, females: 3.2). Increasing trends in incidence were found for some groups.

CONCLUSIONS

We found a higher burden of stomach cancer in indigenous populations globally, and rising incidence in some indigenous groups, in stark contrast to the decreasing global trends. This is of major public health concern requiring close surveillance and further research of potential risk factors. Given evidence that improving nutrition and housing sanitation, and Helicobacter pylori eradication programmes could reduce stomach cancer rates, policies which address these initiatives could reduce inequalities in stomach cancer burden for indigenous peoples.

Population groups in dietary transition

Background

Little is known about the effects of dietary acculturation in minority groups in the Nordic countries, including immigrants from non-Western societies.

Methods

A search was performed in Medlin33e/PubMed and SweMed+ for articles published in 1990–2011.

Results

A total of 840 articles were identified, with a final 32 articles used to tabulate results which were included in the primary analysis. High rates of vitamin D deficiency (23 articles) were found in immigrants of non-Western origin; deficiency rates were very high among both pregnant and non-pregnant women, and also among children, with young children of immigrant parents showing 50 times higher risk for rickets when compared to children of indigenous parents. The risk of iron deficiency (two articles) was high among immigrant women, while the results were inconclusive regarding children. High rates of dental caries (seven articles) were found among pre-school and younger school children of immigrant origin, while the risk of caries was not as evident among older children. In a secondary analysis, including 48 articles (results not tabulated), overweight and obesity (14 articles) were seen in many immigrant groups, resulting in a high prevalence of diabetes (2 review articles from a total of 14 original articles) and incidence of coronary heart disease (CHD; seven articles). For hypertension (three articles), dyslipidemia (four articles), and dietary patterns among immigrants (10 articles), the results were contradictory.

Conclusions

Risk of vitamin D deficiency is alarmingly high in the Nordic countries among immigrants of non-Western origin, especially among women. Dental caries is high among immigrant children aged 0–7 years due to a higher intake of sugary products. Overweight and obesity, associated with a higher risk of diabetes and CHD, are prevalent in many immigrant groups and need further attention.

A Community-Based, Environmental Chronic Disease Prevention Intervention to Improve Healthy Eating Psychosocial Factors and Behaviors in Indigenous Populations in the Canadian Arctic

Diet-related chronic diseases are highly prevalent among indigenous populations in the Canadian Arctic. A community-based, multi-institutional nutritional and lifestyle intervention—Healthy Foods North—was implemented to improve food-related psychosocial factors and behaviors among Inuit and Inuvialuit in four intervention communities (with two comparison communities) in Nunavut and the Northwest Territories, Canada, in 2008. The 12-month program was developed from theory (social cognitive theory and social ecological models), formative research, and a community participatory process. It included an environmental component to increase healthy food availability in local stores and activities consisting of community-wide and point-of-purchase interactive educational taste tests and cooking demonstrations, media (e.g., radio ads, posters, shelf labels), and events held in multiple venues, including recreation centers and schools. The intervention was evaluated using pre- and postassessments with 246 adults from intervention and 133 from comparison communities (311 women, 68 men; mean age 42.4 years; 78.3% retention rate). Outcomes included psychosocial constructs (healthy eating knowledge, self-efficacy, and behavioral intentions), frequency of healthy and unhealthy food acquisition, healthiness of commonly used food preparation methods, and body mass index (kg/m2). After adjustment for demographic, socioeconomic status, and body mass index variables, respondents living in intervention communities showed significant improvements in food-related self-efficacy (β = 0.15, p = .003) and intentions (β = 0.16, p = .001) compared with comparison communities. More improvements from the intervention were seen in overweight, obese, and high socioeconomic status respondents. A community-based, multilevel intervention is an effective strategy to improve psychosocial factors for healthy nutritional behavior change to reduce chronic disease in indigenous Arctic populations.

Breast cancer in the Arctic--changes over the past decades

The purpose of this study is to review the current literatures on breast cancer (BC) in the Arctic, especially the trends in incidence during the last decades and the possible explanations. The design of this study is a literature review. The scientific literature concerning BC were reviewed, especially focusing on the Arctic and the special conditions that exist in this region. Breast cancer incidence is increasing all over the world, including in the Arctic. The enormous transition in health conditions and lifestyle in the Arctic might be contributing to the known risk factors. In Greenland, the age at menarche has diminished by 3 years during the course of 100 years, and the number of children per women as well as the duration of breastfeeding is decreasing. Obesity and intake of saturated fat is increasing and the intake of traditional food rich in unsaturated fat and vitamin D decreasing. Smoking and alcohol consumption in the Arctic has been relatively high but is now decreasing. More focus on genetic susceptibility in relation to BC has identified the specific BRCA1 founder mutation in the Greenlandic population, which might appear to be an important risk factor. However, the known established risk factors alone cannot account for the increasing trend observed. Studies suggest that environmental contaminants such as persistent organic pollutants (POPs) including perfluorinated compounds increase the risk of BC possibly in conjunction with certain genetic polymorphisms involved in carcinogen activation. The lipophilic POPs such as polychlorinated biphenyls and organochlorine pesticides are found at very high levels in the Arctic population. Several factors can explain the increasing incidence of BC in the Arctic. The transition in lifestyle and health conditions unfortunately increases the known risk factors of BC. Moreover, the population of the Arctic might show up to be especially vulnerable because of the contemporary high burden of POPs and genetic susceptibility.

Incidence of pancreatic cancer in Greenland 2000-2010

Background

Inuit people are known to be at an increased risk of cancers usually uncommon to the western world such as cancers of the nasopharynx and salivary glands. But what is the trend regarding pancreatic cancer?

Objective

To determine the incidence of pancreatic cancer (PC) in Greenland compared with Denmark in the period 2000–2010.

Study design

Retrospective register-based study. Cases were retrieved from The Danish Cancer Register and The Greenlandic Patient Register and stratified in 5-year age intervals for each year. Age-standardized incidence ratios (SIR) for each year for Greenland compared with Denmark were calculated using the number of cases and the number of inhabitants in each 5-year age interval and in each country. The average SIR for the entire period was calculated using a weighted average.

Results

The study revealed a SIR of 2.38 (95% CI: 1.97–2.86; p<0.0001) indicating a significantly increased incidence of PC in Greenland compared with Denmark. A linear regression analysis showed no significant change in the SIR over time (p for trend 0.25) as well as no significant change isolated in Greenland (p for trend 0.8). Furthermore, the Inuit were significantly younger at the time of diagnosis (mean 62.7 vs. 70.0; p<0.0001).

Conclusions

The age-standardized incidence of PC is 138% higher in Greenland than in Denmark. A part of this could be explained by a higher prevalence of smoking and DM-2. However, the impact of genetic factors cannot be disregarded and should be subjected to further investigation.