Abstract

Background: This report provides clinical-pathological and epidemiologic data on four cases of malignant mesothelioma following prior multimodality therapy, including therapeutic radiation given for a primary childhood malignancy, including neuroblastoma, malignant mesothelioma, embryonal rhabdomyosarcoma (ERMS), and acute myelomonocytic leukemia (AMML).
Material and Methods: The medical records from the three US patients were reviewed by the senior author who provided medical testimony for litigation, now resolved. Medical records were reviewed and summarized by the attending physicians in the Republic of Korea.
Result: The diagnoses of the initial cancers and secondary mesothelioma were confirmed by standard medical imaging, and histologic and immunohistochemical methods. The latencies were 51 years, 34 years, 36 years, and 17 years respectively after neuroblastoma, childhood metastatic mesothelioma, embryonal rhabdomyosarcoma, and acute myelomonocytic leukemia (AMML). Cases 1, 2, and 3 were treated with debulking surgery and standard chemoradiotherapy and survived for 12, 13, and 13 months respectively. All three were exposed para-occupationally and/ or in their households to asbestos. Case 4 received multiagent chemotherapy, whole body radiation, and allogeneic bone marrow transplant for AMML and standard chemotherapy and surgery for mesothelioma but was never exposed to asbestos.
Conclusion: The relevant epidemiology data on radiation-induced mesothelioma and the lesser contributory role of household or environmental/occupational exposure to asbestos in Cases 1, 2, and 3 suggest that therapeutic radiation was the primary cause of the secondary malignant mesothelioma in these three cases. Any additive or synergistic effect of asbestos exposure to therapeutic radiation is uncertain. The etiology of secondary malignant mesothelioma associated with therapeutic radiation remains a fertile field of investigation.

Keywords:Malignant mesothelioma; Therapeutic radiation; Chrysotile exposure; Second malignant neoplasm after primary neoplasm in childhood