Serum carotenoids and alpha-tocopherol and risk of nonmelanoma skin cancer.
BACKGROUND
Carotenoids and tocopherols have been hypothesized to protect against cancer.


METHODS
We prospectively evaluated associations of several carotenoids and alpha-tocopherol with risk of nonmelanoma skin cancer using serum collected at baseline from 302 subjects in the Isotretinoin-Basal Cell Carcinoma Prevention Trial. All subjects had at least two BCCs in the 5 years prior to randomization. During 5 years of follow-up, 70 subjects did not develop a nonmelanoma skin cancer, 221 developed a BCC, and 85 developed a squamous cell carcinoma (SCC). Cox proportional hazards models were used to estimate risk ratios. Models were stratified by clinical center and gender and adjusted for age, solar damage, skin type, number of prior BCCs and/or SCCs, treatment group, body mass index, and serum low-density lipoprotein-cholesterol and high-density lipoprotein-cholesterol.


RESULTS
Risk of developing a subsequent BCC was not related to serum levels of any of the carotenoids measured or to alpha-tocopherol. Serum levels of alpha-carotene, beta-carotene, lycopene, and alpha-tocopherol also were not independently related to risk of a subsequent SCC. However, serum lutein, zeaxanthin, and beta-cryptoxanthin were positively related to SCC risk; risk ratios for subjects in the highest versus lowest tertiles of these micronutrients were 1.63 [95% confidence interval (95% CI) 0.88-3.01; P for trend = 0.01], 2.40 (95% CI 1.30-4.42; P for trend = 0.01), and 2.15 (95% CI 1.21-3.83; P for trend = 0.09), respectively.


CONCLUSIONS
Additional research is needed on the relationship of carotenoids to SCC risk in the general population and in subsets of the population who are at increased risk.
Dorgan
Joanne F
JF
Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA. jf_dorgan@fccc.edu
Boakye
Naana A
NA
Fears
Thomas R
TR
Schleicher
Rosemary L
RL
Helsel
William
W
Anderson
Christa
C
Robinson
June
J
Guin
Jere D
JD
Lessin
Stuart
S
Ratnasinghe
Luke D
LD
Tangrea
Joseph A
JA
D000328:Adult; D017677:Age Distribution; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000453:epidemiology / Q000473:pathology; D002338:Carotenoids / Q000097:blood* / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011336:Probability; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000453:epidemiology / Q000473:pathology*; D016896:Treatment Outcome; D024502:alpha-Tocopherol / Q000097:blood* / Q000627:therapeutic use*
D002338:Carotenoids; C041635:alpha-carotene; D024502:alpha-Tocopherol