Evidence was identified through a systematic search of the databases MEDLINE (1966 to October 2005), EMBASE (1980 to October 2005), CANCERLIT (1975 through September 2001), and the Cochrane Library (2005, Issue 3). "Mesothelioma" (Medical Subject Heading (MeSH) and Excerpta Medica Tree (EMTREE)), "pleural neoplasms" (MeSH), "pleura mesothelioma" (EMTREE), "malignant mesothelioma" (EMTREE), and "mesothelioma" as a text word were combined with "radiotherapy" (MeSH, EMTREE), and the following text words: "radiotherapy", "radiation", and "irradiation." Those terms were then combined with search terms for the following publication types and study designs: practice guidelines, systematic reviews, meta-analyses, reviews, randomized controlled trials, controlled clinical trials, clinical trials, multicenter studies, comparative studies, and prospective studies.
In addition, conference proceedings of the American Society of Clinical Oncology (ASCO) (1995-2005) and the American Society for Therapeutic Radiation and Oncology (ASTRO) (2000-2005) were searched for abstracts of relevant trials. The Canadian Medical Association Infobase (http://mdm.ca/cpgsnew/cpgs/index.asp) and the National Guidelines Clearinghouse (http://www.guideline.gov/index.asp) were also searched for existing evidence-based practice guidelines. The reference lists from those sources were searched for additional trials, as were the reference lists from relevant review articles.
Study Selection Criteria
Articles published as full reports or as abstracts were included if they focused on radiotherapy (radical, adjuvant or palliative) for patients with malignant pleural mesothelioma (MPM); reported data on survival, quality of life (QOL), or toxicity; and were:
- Randomized trials comparing radiation therapy alone or as part of a planned combined modality regimen to no radiation therapy or best supportive care; or
- Non-randomized prospective studies of radiation therapy, alone or as part of a planned combined modality regimen involving more than 40 patients; or
- Meta-analyses or systematic reviews
Trials that focused on a modality other than radiation therapy, except when radiation was part of a planned combined modality regimen, were excluded. Trials published in a language other than English were also not considered.