Apr 5, 2010 - Mesothelioma: Years of Life Lost Due to Asbestos
Recent results were published from a case study taken in Taiwan that analyzed the burden of mesothelioma- the expected years of life that are lost due to being exposed to asbestos and developing the disease.
The researchers wanted to come up with an indicator of the burden of mesothelioma, defined by the estimation of time a patient’s life was shortened by having the cancer. The study looked at a total of 423 cases of mesothelioma, 91% of which originated in the pleura or peritoneum. The main sources of data came from the Taiwan Cancer Registry from 1979 to 2005, and most likely, due to underreporting or misdiagnosis, the actual number of cases would have been much higher.
Mesothelioma is a rare cancer in which malignant cells are found in the protective sac that covers the lungs, heart and abdomen. Pleural mesothelioma is the most common type and refers to the thoracic-based form of this disease. Asbestos exposure is the main risk factor, although due to a long latency period, symptoms of mesothelioma may not develop until decades after exposure.
The majority of asbestos used in Taiwan is imported, although this practice has greatly declined since the passage of the Toxic Substance Control Act by the Environmental Protection Agency in the early 1990’s. Because of the latency period between exposure and development of symptoms of mesothelioma, the study shows that there continues to be an increase in cases being diagnosed despite decreased use of asbestos.
The average age at time of diagnosis was 58 years old, and the median survival rate was less than 8 months for males and 13.5 for females. Based on this, researchers indicated the average expected years of life lost (EYLL) to be a little over 14 years. The intention of the study was to prove that there is a high burden of mesothelioma, and that only by preventing exposure to asbestos completely can this burden be decreased.
Mesothelioma can be avoided by preventing all exposure to asbestos, so implementing bans on the use of asbestos as well as enforcing safety controls is needed. Although more regulations have been enforced in Taiwan, the government still has not put a total ban on the use of asbestos. In addition, awareness of the dangers of the use of asbestos remains low. Until the government acknowledges the risk of asbestos and implements a total ban, exposure will continue and the number of cases of mesothelioma is predicted to increase.