Prediagnostic serum levels of carotenoids and vitamin E as related to subsequent cancer in Washington County, Maryland.
 In 1974 and 1975, serum specimens were collected from 25,802 volunteers in Washington County, Maryland.
 The serum was kept frozen at -73 degrees C until the time of assay.
 Prediagnostic samples from 436 cancer cases and 765 matched control subjects have been assayed.
 Nine sites have been studied: colon, rectum, pancreas, lung, melanoma, basal cell of skin, breast, prostate, and bladder.
 Serum beta-carotene levels showed a strong protective association with lung cancer, suggestive protective associations with melanoma and bladder cancer, and a suggestive but nonprotective association with rectal cancer.
 Serum vitamin E levels had a protective association with lung cancer; none of the other sites showed impressive associations.
 Low levels of serum lycopene were strongly associated with pancreatic cancer and less strongly associated with cancer of the bladder and rectum.
