- Mesothelioma
- Chronic obstructive lung disease
- Cancer (carcinoid tumour)
The worker was employed as a sheet metal worker from 1968 until 2006; a 38-year period. His death certificate identified left bronchopneumonia as the cause of death. The worker's estate appealed the following issues: a) entitlement to benefits for mesothelioma; b) entitlement to benefits for a carcinoid tumour; and, c) entitlement to benefits for COPD as a cause of death.
The Vice-Chair denied the appeal.The worker's representative submitted that the failure of the death certificate to identify mesothelioma "is not sufficient to refute his prior diagnosis" because "cancer misclassifications occur on 15-35% of death certificates." An article provided highlighted the importance of "population based registries" which rely on death certificates to determine the incidence of deaths by different types of cancer. The article notes that errors by the individuals determining the cause of death may occur with some frequency (between 15% and 35%), resulting in misclassification. The authors of the article caution researchers using cancer-registry data, and make a number of recommendations to improve the accuracy of such registries. The worker had an initial, or working, diagnosis of mesothelioma but this diagnosis was not confirmed by the autopsy. The Vice-Chair stated that the autopsy results should be preferred to the clinical diagnosis. Dr. Masson's conclusions were based on a sample of the tumours which were subjected to histological testing, and revealed to be neuroendocrine tumours. These conclusions were much more likely to be accurate than the speculative diagnosis based on unsuccessful biopsy samples. The diagnosis of mesothelioma was therefore ruled out.Further, the mere presence of asbestos insulation in buildings constructed prior to 1982 did not lead to a determination that the worker had significant exposure to asbestos. As a metal worker, the worker would not ordinarily have prepared and applied insulation. It was not demonstrated that the worker had "continuous and repetitive" exposure or exposure to a "significant amount" of asbestos. A causal link between asbestos exposure and certain pulmonary carcinoid tumors has not been clearly established. There is a causal connection between smoking and pulmonary carcinoid tumours. The evidence also did not support a determination that the worker's occupational exposure to asbestos, welding fumes and gases, or solvents, was a significant contributing factor to the development of the carcinoid tumours. Lastly, the final autopsy report from Dr. Masson, dated January 25, 2008, did not identify COPD as a diagnosis. The evidence did not support that COPD was a cause of death. The evidence suggested that the initial diagnosis of COPD may have been erroneous. There was also no evidence that the initial diagnosis of COPD tied the condition to the worker's employment.