The Carotene and Retinol Efficacy Trial (CARET) was a randomized, double-blind,
placebo-controlled trial of the cancer prevention efficacy and safety of a daily combination
of 30 mg of beta-carotene and 25,000 IU of retinyl palmitate in 18,314 persons at high risk
for lung cancer. CARET began in 1985, and the intervention was halted in January 1996, 21
months ahead of schedule, with the twin conclusions for definitive evidence of no benefit and
substantial evidence of a harmful effect of the intervention on both lung cancer incidence
and total mortality. CARET continued to follow and collect endpoints on their participants
through 2005. During the active intervention phase of CARET, serum, plasma, whole blood, and
lung tissue specimens were collected on participants. These biospecimens make up the CARET
Biorepository.
The CARET Biorepository is a valuable resource for population-based studies of the major
human cancers. During CARET's twenty years of follow-up (1985-2005), we have received reports
of 1,445 participants with lung cancer, 901 with prostate cancer, 433 with breast cancer, 334
with bladder cancer, 332 with colon cancer, and 1,429 with other cancers. CARET is one of the
few trials that has prospectively collected serum, plasma, whole blood, blood spots (for
DNA), and lung cancer tumor specimens, as well as smoking history and serial food frequency
questionnaires (in some individuals for up to 12 years) in populations at high risk for lung
cancer. This wealth of information in over 18,000 individuals makes the CARET Biorepository a
special resource for cancer researchers.
Phase:
Phase 4
Details
Lead Sponsor:
Fred Hutchinson Cancer Research Center
Collaborator:
National Cancer Institute (NCI)
Treatments:
Beta Carotene Carotenoids Retinol palmitate Vitamin A