There is a considerable amount of anecdotal data stating that mesothelioma affects men and women in different ways. While men are much more likely to be diagnosed with this difficult disease, when women are diagnosed there seems to be some differences in origin site, prognosis and overall survivability as compared to men. Researchers in Australia have recently released results from a study looking at incidence trends between male and female patients with mesothelioma in New South Wales, Australia.

Introduction to the Study

To examine the incidence trends among male and female patients diagnosed with mesothelioma in New South Wales, Australia, researchers examined case files from the New South Wales Central Cancer Registry (NSW CCR) and the New South Wales Workers Compensation (Dust Diseases’) Board. The NSW CCR maintains a list of all cancer cases diagnosed in New South Wales since 1972 and notification of new cases is a statutory requirement. The Dust Diseases’ Board is a statutory authority that provides compensation for workers diagnosed with dust-related diseases who were employed in New South Wales. The Dust Diseases’ Board has compensated about 60% of the mesothelioma cases reported to the NSW CCR, so it reports a smaller series of numbers than does the NSW CCR.

Results

A total of 3090 mesothelioma cases were reported to the NSW CCR between 1972 and 2004. 456 of those were women’s cases, 2634 were from men. This leaves an incidence rate of 14% women, 86% men. Pleural mesothelioma, as would be expected, was the most diagnosed type of the disease. Of women diagnosed with mesothelioma, 15% had peritoneal mesothelioma, while only 6% of men were given that diagnosis. The Dust Diseases’ board has compensated 1995 mesothelioma patients over their history, with 95% of those compensated being men and women the remaining 5%. In terms of pleural vs. peritoneal disease, 94% of those compensated had pleural mesothelioma, while 5% had peritoneal mesothelioma.

Occupational data was never recorded for the NSW CCR, but it was recorded by the Dust Diseases’ Board. For men, the top five occupations most often represented in the mesothelioma compensation statistics were:

• Carpenter
• Fitter
• Trades assistant
• Electrician
• Asbestos Worker

For women, the top five occupations listed were:

• Steam press operator
• Process worker
• Clerical worker
• Textile machine operator
• Cleaner

The researchers did not find any gender-based difference in disease latency (M=43.7 years vs. W=42.8 years), but they did find a large difference between pleural and peritoneal mesothelioma, with peritoneal mesothelioma having a much shorter latency period. In men, latency between the two diseases was 38.8 years vs. 44 years and in women 29.7 years vs. 43.6 years. As would be expected, histological classification showed epithelial mesothelioma as the most common subtype and sarcomatous mesothelioma having the worst prognosis. Regarding long-term survival, statistics were poor, as is the case in the majority of mesothelioma diagnoses. Overall, women survived longer than men (10.4 months vs. 8.5). When broken down by gender and split between pleural and peritoneal disease, men did not see a statistically significant difference in survival between the two (pleural, 8.6 months vs. peritoneal, 5.6 months), but women showed a very significant difference between them (pleural, 9.3 months vs. peritoneal, 43.6 months). However, there were only 6 cases of women being diagnosed with peritoneal mesothelioma so the number may be too small to draw any conclusions from.

Conclusion

The results of the study have quantified much of the anecdotal data that exists on the differences between how men and women experience mesothelioma. The researchers once again showed the great difference in disease incidence between men and women, with men much more likely to be diagnosed. They found that women seemed to have a greater propensity for peritoneal disease than do men. They also found that women were more likely to present with epitheloid mesothelioma than either of the other two subtypes and they had a better survivability average, even if only slight. However, the clinical differences, especially in terms related to treatment and overall prognosis remain quite similar.

Mesothelioma remains a very difficult to disease to treat. Researchers around the world are hopeful that new studies and better research will increase both our knowledge of the disease and our ability to treat it.

Labels: mesothelioma