Malignant Pleural Mesothelioma in Parts of Japan in Relationship to Asbestos Exposure

Abstract

Malignant pleural mesothelioma is induced by asbestos exposure. Many reports have described this situation in America and European countries, but a few have been published in Japan. In this study malignant pleural mesothelioma cases in hospitals located in an area facing the Seto Inland Sea were evaluated. A total of 106 patients were examined with 100 patients having had occupational exposure to asbestos and 6 patients without such histories of asbestos exposure. Ninety seven were male and 9 were female. Ages ranged from 41 to 87 yr with mean of 64.8 ± 5.3 yr. Thirty seven cases showed epithelial type of tumor, 25 biphasic type and 15 showed sarcomatous. The remaining 23 cases had insufficient evidence for typing the tumor. The mean survival rate for all cases was 9.2 ± 11.6 months. Fifty-one patients had occupational histories of shipyard work, 16 patients worked in asbestos cement piping, and the remainder were employed in miscellaneous jobs related asbestos exposure. The duration of asbestos exposure ranged up to 20 yr or longer with the mean of 17.2 ± 8.9 yr and the average latent period for the occurrence of malignant pleural mesothelioma was more than 31 yr with the mean of 37.0 ± 13.3 yr. Quantification of asbestos bodies in the lungs indicated a high concentration in most patients and the major types of asbestos fibers were crocidolite and amosite. Six cases appeared after exposure to chrysotile. These results indicated that ninety four percent of malignant pleural mesothelioma appeared due to the exposure to asbestos including crocidolite and amosite. The remainder may be blamed on exposure to chrysotile.

Downregulation of thymidylate synthase by RNAi molecules enhances the antitumor effect of pemetrexed in an orthotopic malignant mesothelioma xenograft mouse model

“…MPM is most often caused by asbestos exposure with a long latency period, often exceeding 20 years between the first exposure to asbestos and a diagnosis of the disease (3,4). Despite the fact that this type of tumor was once considered rare, the current incidence is predicted to increase globally and peak in the coming decades particularly in developing countries where the use of asbestos is still prevalent (5,6).…”

A seven-year disease-free survivor of malignant pleural mesothelioma treated with hyperthermia and chemotherapy: a case report

“…Its incidence is currently increasing worldwide because of the extent of asbestos exposure between the years 1965 and 1980 [1,2]. MPM has a poor prognosis, mainly because of its inherent resistance to conventional treatment.…”

“…Malignant pleural mesothelioma (MPM) was once a rare finding, but its incidence is increasing worldwide, most likely because of widespread exposure to asbestos [1,2]. MPM is considered to have a poor prognosis, and complete surgical resection is the only curative treatment.…”

Clinical investigation of malignant mesothelioma in Japan

“…An association between MM and AE has been well-known worldwide since the 1950s (Magnani et al 2000;Newhouse and Thompson 1965;Rees et al 1999). There is so far one report that demonstrated association between AE and MM in western parts of Japan (Kishimoto et al 2004). Patients who have a history of occupational AE and developed MM are provided worker's compensation in Japan.…”