Early Diagnosis of Lung Cancer and Mesothelioma in Prior Asbestos Workers
Condition: Lung Cancer; Mesothelioma
MeSH terms: Lung Neoplasms; Mesothelioma; Mesothelioma, Malignant
Study type: Observational

Summary: 
      Occupational exposure to asbestos is known increase the risk of developing cancer of the
      lungs (bronchogenic carcinoma) or of the pleura (mesothelioma). Symptoms are subtle and
      non-specific, diagnosis is often late and the prognosis consequently is dismal. Currently
      there is no accepted non-invasive tool for the early diagnosis of mesothelioma or lung cancer
      in asbestos-exposed subjects. In the last decade, low-dose computed tomography (LDCT) has
      been successfully developed and validated for the early diagnosis of lung cancer in high-risk
      smokers. Malignant mesothelioma might, in an early stage, resemble a benign pleural plaque,
      which is a common finding after asbestos exposure. We target to develop low-dose CT as a tool
      to serially image the pleural plaques, quantify their individual and overall volume, compute
      the growth rate with time, and, as such, identify the presence of mesothelioma early, before
      symptoms occur.
    

Detailed description: 
      Background and Purpose:

      Asbestos exposure may result in several different diseases to the lung and to the lining of
      the lung, the so-called pleura. Mostly they are benign, but there are two common malignant
      diseases in people with prior asbestos exposure, the so-called mesothelioma - which
      originates from the pleura - and cancer of the lung. Symptoms of any of these malignant
      diseases generally do not appear for 10-35 years after the first asbestos exposure, and
      include shortness of breath, chronic or new cough, coughing of blood, chest pain or weight
      loss. Unfortunately, these symptoms are most often causes by very advanced diseases, when
      patients can no longer be cured. Currently there is no accepted tool for the early diagnosis
      of mesothelioma or lung cancer in asbestos-exposed subjects available. Standard of care
      includes regular chest radiographs, which are not sufficient to show mesothelioma or lung
      cancer in an early stage.

      A screening CT examination, also called CAT scan, of the lungs will be performed without
      intravenous contrast. The CT examination as such is not an experimental procedure, CAT scans
      are performed routinely since decades. However, in this particular case, this albeit standard
      examination is performed for the purposes of research only, it is not part of standard of
      care. The screening CT examination of the lungs takes less than 10-20 minutes to perform.

      If no abnormalities are found on the initial examinations, you will be examined with one
      repeat screening CT of the chest after one year.

      If pleural plaques or a nodule in the lungs is seen on your baseline CT, this will lead to
      further testing. Quite likely (approximately 1 in 3 chance), you will be invited for a
      follow-up CT 3 or 6 months. Further investigations will be chosen according to standard of
      care and will be explained to you at the time. These will be coordinated by your physician
      with Dr. Marc de Perrot, Department of Thoracic Surgery.

      Secondly, there is evidence in other types of cancers such as cancers of the prostate and
      ovary, that analysis of blood may reveal protein markers that indicate the presence of cancer
      in the body. A companion blood analysis study is being undertaken in an effort to discover
      such markers for lung cancer and mesothelioma, so that the accuracy of CT-scan diagnosis for
      lung cancer may be further improved.

      Both at the time of your baseline screening CT and at your annual follow-up screening CT, you
      will be asked to provide 5 ml (approximately 2 teaspoons full) blood sample through a needle
      stick. A blood-taking technician employed by the University Health Network or a certified
      nurse will carry out this procedure. Purpose of this study is to search in the blood for
      so-called "markers", substances in the blood which indicate that there is a cancer in the
      lungs or pleura.

      Most of these markers are still in development, thus your blood will be stored and analyzed
      at a future date.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        prior exposure to asbestos and or documented pleural plaques
      
Keywords: Lung Cancer; Mesothelioma; Asbestos; Screening; Early Diagnosis