Lung cancer * 8: Management of malignant mesothelioma

Abstract

Malignant mesothelioma is a relatively common malignant tumour which is associated with prior exposure to asbestos. The diagnosis, histology, prognosis, and management of this disease are reviewed. The disappointing outcome of most curative treatment strategies is discussed and improved palliation is highlighted. Malignant mesothelioma is a challenging disease that understandably causes considerable distress and anxiety to patients, relatives, and clinicians. The incidence of mesothelioma has been steadily increasing over the past 30 years, and is expected to continue until 2020 with a projected 1300 cases each year. The 1940s male birth cohort is particularly affected, mesothelioma accounting for approximately 1% of all deaths.1–3 The incidence increases with age and is approximately 10 times higher in men aged 60–64 years than in those aged 30–34. There is an association with the inhalation of asbestos fibres, which frequently has occurred years previously and sometimes in a seemingly low dose. Mesothelioma is rare in patients without any direct occupational exposure or indirect paraoccupational or environmental exposure.4 Current estimates suggest an occupational history is obtained in over 90% of patients.5 There is no evidence to suggest a safe or threshold level of exposure, but the risk is low where exposure is of low intensity. Few populations are exposed only to one type of asbestos fibre. The first description of an association between malignant mesothelioma and asbestos exposure was by Wagner in patients exposed to crocidolite in South African mines.6 All types of asbestos fibre can cause mesothelioma, although crocidolite is considered a higher risk. Chrysotile, crocidolite, and amosite have been the most commonly used in industry, accounting for 95%, 3%, and 1%, respectively, of the world’s production of asbestos. Necroscopic studies have led to the determination of asbestos fibre load and the demonstration of a dose related effect,7 …