The MEDLINE (1993 through March 2005 week 1), EMBASE (1980 through 2005 week 10), CANCERLIT (1993 through October 2002), and Cochrane Library databases (2004, Issue 4) were systematically searched for relevant papers. MEDLINE and CANCERLIT were searched using the following medical subject headings: "carcinoma, renal cell," "kidney neoplasms," "nephrectomy," and "immunotherapy." EMBASE was searched using the following Excerpta Medica tree terms: "kidney tumor," "kidney cancer," "nephrectomy," and "immunotherapy." In each database, those subject headings were combined with variations of disease and treatment-specific text words or phrases (e.g., "kidney or renal cell cancer," "nephrectomy," "interferon," "interleukin"). Those terms were then combined with search terms for the following publication types and study designs: randomized controlled trial, controlled clinical trial, meta-analysis, systematic review, and practice guideline.
In addition, the conference proceedings from the annual meetings of the American Society of Clinical Oncology (1995-2005) were searched for abstracts of relevant trials. The Canadian Medical Association Infobase (http://mdm.ca/cpgsnew/cpgs/index.asp) and the National Guideline Clearinghouse (http://www.guideline.gov/) were searched for existing evidence-based practice guidelines.
Relevant articles and abstracts were selected and reviewed by three reviewers, and the reference lists from those sources were searched for additional trials, as were the reference lists from relevant review articles.
Study Selection Criteria
Articles were selected for inclusion in this systematic review if they met any of the following criteria:
- They were published reports or abstracts of randomized controlled trials (RCTs) or meta-analyses comparing cytoreductive nephrectomy plus immunotherapy versus immunotherapy alone in adult patients with metastatic renal cell cancer (RCC) and reported any one of the following outcomes: overall survival and/or progression-free survival, response rate, adverse effects, or quality of life.
- They were systematic reviews or evidence-based guidelines relevant to the guideline question.