Clinical research in surgical oncology: an analysis of ClinicalTrials.gov.

Background: The objective of this study was to provide a descriptive analysis of registered clinical trials in surgical oncology at ClinicalTrials.gov.

Methods: Data was extracted from ClinicalTrials.gov using the following search engine criteria: "Cancer" as Condition, "Surgery OR Operation OR Resection" as Intervention, and Non-Industry sponsored. The search was limited to Canada and the United States and included trials registered from January 1, 2001 to January 1, 2011.

Results: Of 9,961 oncology trials, 1,049 (10.5%) included any type of surgical intervention. Of these trials, 125 (11.9%, 1.3% of all oncology trials) assessed a surgical variable, 773 (73.7%) assessed adjuvant/neoadjuvant therapies, and 151 (14.4%) were observational studies. Of the trials assessing adjuvant therapies, systemic treatment (362 trials, 46.8%) and multimodal therapy (129 trials, 16.7%) comprised a large focus. Of the 125 trials where surgery was the intervention, 59 trials (47.2%) focused on surgical techniques or devices, 45 trials (36.0%) studied invasive diagnostic methods, and 21 trials (16.8%) evaluated surgery versus no surgery. The majority of the 125 trials were nonrandomized (72, 57.6%).

Conclusions: The number of registered surgical oncology trials is small in comparison to oncology trials as a whole. Clinical trials specifically designed to assess surgical interventions are vastly outnumbered by trials focusing on adjuvant therapies. Randomized surgical oncology trials account for <1% of all registered cancer trials. Barriers to the design and implementation of randomized trials in surgical oncology need to be clarified in order to facilitate higher-level evidence in surgical decision-making.