Design and recruitment for retinoid skin cancer prevention (SKICAP) trials. The Southwest Skin Cancer Prevention Study Group.
The retinoid skin cancer prevention (SKICAP) trials are a set of double-blind, randomized, placebo-controlled clinical trials. The SKICAP-actinic keratoses (AK) trial tests the hypothesis that daily supplementation of retinol (25,000 IU) for 5 years reduces the incidence of skin cancers in high-risk individuals, those with a history of greater than ten clinically or pathologically diagnosed AK and, at most, one prior pathologically confirmed cutaneous squamous cell carcinoma (SCC) or basal cell carcinoma (BCC). The SKICAP-SCC/BCC (S/B) trial tests the hypothesis that daily supplementation of retinol (25,000 IU) or 13-cis-retinoic acid (5 or 10 mg) for 3 years reduces skin cancer incidence in very high-risk individuals, those with a history of at least four pathologically confirmed SCCs or BCCs. Between 1984 and 1988, 2800 participants were enrolled at two clinics on the SKICAP-AK trial; and between 1985 and 1990, a total of 719 participants were enrolled at four clinics on the SKICAP-S/B trial. The initial recruitment strategy was referral by dermatologists, but low accrual necessitated the use of other strategies to achieve enrollment goals, which included involving additional clinics and using paid trial-specific advertisements in print and electronic media. Thirteen % of the SKICAP-AK participants and 36% of the SKICAP-S/B participants were enrolled through dermatologist referral, whereas paid advertisements resulted in enrollment of 87% of SKICAP-AK and 43% of SKICAP-S/B participants. A population-based skin cancer registry was used to identify and enroll the remaining 21% of the SKICAP-S/B participants.(ABSTRACT TRUNCATED AT 250 WORDS)
Moon
T E
TE
Department of Biomathematics, University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
Levine
N
N
Cartmel
B
B
Bangert
J
J
Rodney
S
S
Schreiber
M
M
Peng
Y M
YM
Ritenbaugh
C
C
Meyskens
F
F
Alberts
D
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016588:Anticarcinogenic Agents / Q000627:therapeutic use*; D002985:Clinical Protocols; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007642:Keratosis / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012042:Registries; D012107:Research Design; D012176:Retinoids / Q000627:therapeutic use*; D012878:Skin Neoplasms / Q000209:etiology / Q000517:prevention & control*
D016588:Anticarcinogenic Agents; D012176:Retinoids