Abstract
BACKGROUND: Although participation in cancer clinical trials is low, little is known about the number of available clinical trials, and open spots for patients. Moreover, it is unclear what the relationship is between clinical trial openings and the incidence and mortality of cancer subtypes. METHODOLOGY: We identified the number of phase I, phase II and phase III registered at clinicaltrials.gov by cancer (tumour) type. All counts were over the preceding 5 years (2008-2013). We compared these counts against the incidence and prevalence of disease reported by Surveillance, Epidemiology and End Results (SEER) database for 32 common cancers. RESULTS: From 2008 to 2013, 3879 phase I trials, 4982 phase II trials and 1379 phase III trials concerning a cancer subtype were registered in clinicaltrials.gov. These trials had a cumulative proposed recruitment of 203,396, 421,502 and 697,787 patients, respectively. Trial enrollment varied by tumour type, with both over and under-representation occurring. CONCLUSION: Opportunities to enroll in clinical trials vary by phase and tumour type. Oncologists must remain committed to clinical trials.