Pancreatic and Periampullary Tumors in Greenland Inuit
Condition: Pancreatic Neoplasms; Periampullary Neoplasms
MeSH terms: Neoplasms; Pancreatic Neoplasms
Study type: Observational

Summary: 
      Especially since the Second World War the indigenous population in the Arctic, the Inuit have
      gone through a Westernization, which has improved the health conditions but also changed the
      disease panorama with an increasing incidence of cancer. This is exemplified by a decrease in
      physical activity, due to the depletion of the Greenlandic hunting traditions, tobacco
      smoking and unhealthy diet. At the beginning of the westernization, malignant diseases were
      highly uncommon, but they started to increase due to the increasing life expectancy and
      changes in lifestyle. The incidence of pancreatic and periampullary cancer has been reported
      to be the same among Inuit in Canada, Denmark, and the United States but with a higher
      incidence than among the Caucasian population in the three countries.

      The aim with this study was to investigate the results of pancreatic surgery for pancreatic
      and periampullary tumors in Inuit patients in Greenland at to compare the outcome of surgery
      and the overall survival with a cohort of Danish patients.
    

Detailed description: 
      Study design. The study is a retrospective, descriptive register study based on data from a
      prospectively maintained database. The study is a comparison of two cohorts, all Inuit
      patients living in Greenland, who had pancreatic operations for pancreatic and periampullary
      tumors - either preoperatively verified or suspected - at Rigshospitalet, Copenhagen
      University Hospital from 31. January 1999 to 31. January 2021. Danish patients living in
      Greenland were not included in the study. Inuit patients were compared with a cohort of
      Danish patients with same diagnosis and same range of age operated during the same period at
      the hospital. All diagnoses were histologically verified. Data recruitment include all
      patients operated between January 31, 1999 and January 31, 2021 with follow-up until December
      31 after which data will be evaluated. The study is reported according to the STROCSS
      guidelines (www.strocssguideline.com).

      Study population. The study includes 2326 consecutive patients, 47 inuit and 2279 Danish
      patients between 41 and 79 years (age range based on the inuit patients). There are 1,208
      patients with malignant tumours of whom 1,020 have adenocarcinoma.

      Data collection Data are collected from our prospectively maintained database of pancreatic
      operations, from the electronic hospital record systems Orbit and EPIC, the Danish National
      Pathology Data Registry, and from the National Register of Death. All Danish Nationals
      including citizens in Greenland have a unique Central Person Registration number that enables
      searching of health data.

      Outcomes. Relevant postoperative complications are recorded in the study and include leakage
      from the pancreatic, bile or gastrojejunal anastomosis, intraabdominal hemorrhage and abscess
      formation or other complications with severe or fatal outcome. Outcomes are defined as
      postoperative complications and mortality assessed during 30- and 90-days and overall
      survival (OS) defined as the time from surgery to death from any cause or censoring at time
      of last follow-up. Hospitalization is defined as postoperative stay until discharge.
      In-hospital mortality is defined as all deaths from time of admission until discharge. Cancer
      specific mortality is defined as death from adenocarcinoma after other causes are censured.

      Statistics. Data are presented as median and range if not otherwise stated. Categorial data
      are presented as numbers or percentage and are analyzed with Fisher's exact test.
      Non-parametric continuous data between subgroups are analyzed with the Mann-Whitney test. The
      Kaplan-Meier method and the cumulative incidence function with correction for competing risks
      are used to estimate OS and the log-rank test to examine the differences between curves. The
      reference population is an age and sex matched Danish standard population. A p < 0.05 is
      considered statistically significant. Statistical analysis is performed with GraphPad Prism
      software version 6.05. (GraphPad, La Jolla, CA).

      Ethics. The study is a descriptive study and conducted in accordance with the principles
      stated in the Declaration of Helsinki. No approval is required according to the Danish
      National Health Board. The study is an observational, retrospective quality assurance project
      according to the guidelines of the Danish Health Data Authority
      (http://Sundhedsdatastyrelsen.dk). No approval is required according to the Danish National
      Health Board. In this respect it has to be noticed that a major part of the Greenlandic and
      Danish patients had died before the study was initiated, and the Regional Ethical Committee
      of the Capital Region of Denmark provided exemption for the study. The use of register data
      follows the General Data Protection Regulation of the European Union and the Danish Data
      Protection Agency. Patients' written consent for using health data was obtained before
      operation. The study and the use of data were consented by the hospital ethical
    

Intervention name(s): outcome following surgery
Intervention type(s): Other
Observational model: Cohort
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Greenland Inuit, both sex, living in Greenland and operated at Copenhagen University
        Hospital Rigshospitalet Danish patients (controls), both sex living in Denmark and operated
        at Copenhagen University Hospital Rigshospitalet