A Pilot for a Case-Control Study of Esophageal Squamous Cell Carcinoma in Western Kenya
Condition: Esophageal Squamous Cell Carcinoma
MeSH terms: Carcinoma; Carcinoma, Squamous Cell; Esophageal Squamous Cell Carcinoma
Study type: Observational

Summary: 
      Background:

        -  Esophageal cancer is the sixth leading cause of cancer deaths worldwide. Two primary
           cell types, squamous cell carcinoma and adenocarcinoma, account for most cases. Of the
           two, esophageal squamous cell carcinoma (ESCC) accounts for more than 80 percent of all
           deaths from esophageal cancer. Many cases occur in certain areas with defined geographic
           boundaries, including parts of Kenya.

        -  Studies of ESCC in developed countries (such as the United States) suggest that heavy
           tobacco and alcohol use, poor diet, and low socioeconomic status are the primary risk
           factors. Males and African Americans are also at higher risk. However, these risk
           factors do not fully explain the prevalence of cases in several of the identified
           geographic areas.

        -  ESCC is the most common cancer seen at Tenwek Hospital in western Kenya, and a notable
           number of patients are 30 years of age or younger.

      Objectives:

        -  To test the feasibility of a new protocol by recruiting visitors to Tenwek Hospital and
           volunteers from the general population for study purposes.

        -  To use the new protocol to obtain blood and urine samples from ESCC cases in Tenwek
           Hospital and from nonpatient volunteers.

      Eligibility:

        -  Hospital patients and volunteers who live within 50 kilometers of Tenwek Hospital in
           western Kenya.

      Design:

        -  All participants will complete a questionnaire and provide blood and urine samples for
           testing.

             -  The questionnaire will include questions about individual and family medical
                history, living conditions, lifestyle, habits, and diet.

             -  Blood and urine samples will be collected from all participants after the
                questionnaire.

        -  Biological samples will be shipped to the United States for further testing.

        -  Treatment will not be offered as part of this study.
    

Detailed description: 
      This pilot study will assess the feasibility of completing the first formal case-control
      study to examine etiologic factors for esophageal squamous cell carcinoma (ESCC) in Kenya and
      will be conducted in Western Kenya, a high-risk area for ESCC.

      Esophageal cancer causes over 380,000 deaths per year and ranks as the sixth leading cause of
      cancer death worldwide. Two primary cell types, squamous cell carcinoma and adenocarcinoma,
      account for most cases. Although the rates of esophageal adenocarcinoma have risen rapidly in
      the United States and elsewhere, ESCC still accounts for 80% of all esophageal cancer cases
      in the world. Many of these cases occur in high-risk areas with sharp geographic boundaries
      within China, Iran, a small region of South America, South Africa, and Kenya. Studies of ESSC
      in economically developed countries, such as the US, point to smoking tobacco, heavy alcohol
      drinking, poor diets deficient in fresh fruits and vegetables, and low socioeconomic status
      as the main etiologic factors. Other independent risk factors may include being male and
      being African-American. Smoking tobacco and heavy alcohol consumption do not explain the
      incidence rates in the high-risk regions because these habits are less common and less
      intensely practiced in these high-risk areas compared to the low risk area. Also, in highrisk
      areas the incidence rates are similar in men and women despite differences in the rates of
      tobacco smoking and alcohol drinking. Therefore, it is important to consider a wide range of
      etiologic factors to explain the high rates of cancer in these populations.

      Tenwek Hospital is a 300 bed mission hospital located in Bomet District, Rift Valley
      Province, approximately 200 miles from Nairobi in the west of Kenya. Tenwek serves as a
      primary health care facility for approximately 400,000 people, and it has become a referral
      center for a broader population. ESCC is the most common malignancy seen at Tenwek Hospital
      and the patients show a very unusual age distribution with 10% of cases less than or equal to
      30 years of age.

      We will conduct a pilot for a case-control study of ESCC at Tenwek Hospital, recruiting
      people that live within 50 km of the hospital. Initial pilot testing showed that neither
      hospital-visitor controls nor general-population controls were practical control sources. We
      now plan to test the feasibility of collecting 50 hospital-based non-cancer patient controls.
      We will then enroll 50 cases and 50 additional hospital-based non-cancer patient controls to
      test all aspects of our protocol. We will ship the biological samples collected from these
      individuals to the US and test their suitability for our intended assays. All subjects will
      be interviewed using a structured questionnaire and will be asked to provide biological
      samples including blood and urine. Environmental risk factors (including lifestyle, habits,
      and diet) will be assessed through questionnaires.
    

Observational model: Case-Control
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        ESCC patients and controls that live within 50 km of Tenwek Hospital
      
Keywords: Case-Control Study; Esophageal Squamous Cell Carcinoma; Risk Factors