B. K. Edwards

BACKGROUND: Experimental and epidemiologic investigations suggest that alpha-tocopherol (the most prevalent chemical form of vitamin E found in vegetable oils, seeds, grains, nuts, and other foods) and beta-carotene (a plant pigment and major precursor of vitamin A found in many yellow, orange, and dark-green, leafy vegetables and some fruit) might reduce the risk of cancer, particularly lung cancer. The initial findings of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC Study) indicated, however, that lung cancer incidence was increased among participants who received beta-carotene as a supplement. Similar results were recently reported by the Beta-Carotene and Retinol Efficacy Trial (CARET), which tested a combination of beta-carotene and vitamin A. PURPOSE: We examined the effects of alpha-tocopherol and beta-carotene supplementation on the incidence of lung cancer across subgroups of participants in the ATBC Study defined by base-line characteristics (e.g., age, number of cigarettes smoked, dietary or serum vitamin status, and alcohol consumption), by study compliance, and in relation to clinical factors, such as disease stage and histologic type. Our primary purpose was to determine whether the pattern of intervention effects across subgroups could facilitate further interpretation of the main ATBC Study results and shed light on potential mechanisms of action and relevance to other populations. METHODS: A total of 29,133 men aged 50-69 years who smoked five or more cigarettes daily were randomly assigned to receive alpha-tocopherol (50 mg), beta-carotene (20 mg), alpha-tocopherol and beta-carotene, or a placebo daily for 5-8 years (median, 6.1 years). Data regarding smoking and other risk factors for lung cancer and dietary factors were obtained at study entry, along with measurements of serum levels of alpha-tocopherol and beta-carotene. Incident cases of lung cancer (n = 894) were identified through the Finnish Cancer Registry and death certificates. Each lung cancer diagnosis was independently confirmed, and histology or cytology was available for 94% of the cases. Intervention effects were evaluated by use of survival analysis and proportional hazards models. All P values were derived from two-sided statistical tests. RESULTS: No overall effect was observed for lung cancer from alpha-tocopherol supplementation (relative risk [RR] = 0.99; 95% confidence interval [CI] = 0.87-1.13; P = .86, logrank test). beta-Carotene supplementation was associated with increased lung cancer risk (RR = 1.16; 95% CI = 1.02-1.33; P = .02, logrank test). The beta-carotene effect appeared stronger, but not substantially different, in participants who smoked at least 20 cigarettes daily (RR = 1.25; 95% CI = 1.07-1.46) compared with those who smoked five to 19 cigarettes daily (RR = 0.97; 95% CI = 0.76-1.23) and in those with a higher alcohol intake (> or = 11 g of ethanol/day [just under one drink per day]; RR = 1.35; 95% CI = 1.01-1.81) compared with those with a lower intake (RR = 1.03; 95% CI = 0.85-1.24). CONCLUSIONS: Supplementation with alpha-tocopherol or beta-carotene does not prevent lung cancer in older men who smoke. beta-Carotene supplementation at pharmacologic levels may modestly increase lung cancer incidence in cigarette smokers, and this effect may be associated with heavier smoking and higher alcohol intake. IMPLICATIONS: While the most direct way to reduce lung cancer risk is not to smoke tobacco, smokers should avoid high-dose beta-carotene supplementation.

BACKGROUND: The American Cancer Society, the National Cancer Institute (NCI), the North American Association of Central Cancer Registries, and the Centers for Disease Control and Prevention, including the National Center for Health Statistics (NCHS), collaborate to provide an annual update on cancer occurrence and trends in the United States. This year's report contains a special feature that focuses on cancers with recent increasing trends. METHODS: From 1992 through 1998, age-adjusted rates and annual percent changes are calculated for cancer incidence and underlying cause of death with the use of NCI incidence and NCHS mortality data. Joinpoint analysis, a model of joined line segments, is used to examine long-term trends for the four most common cancers and for those cancers with recent increasing trends in incidence or mortality. Statistically significant findings are based on a P value of.05 by use of a two-sided test. State-specific incidence and death rates for 1994 through 1998 are reported for major cancers. RESULTS: From 1992 through 1998, total cancer death rates declined in males and females, while cancer incidence rates declined only in males. Incidence rates in females increased slightly, largely because of breast cancer increases that occurred in some older age groups, possibly as a result of increased early detection. Female lung cancer mortality, a major cause of death in women, continued to increase but more slowly than in earlier years. In addition, the incidence or mortality rate increased in 10 other sites, accounting for about 13% of total cancer incidence and mortality in the United States. CONCLUSIONS: Overall cancer incidence and death rates continued to decline in the United States. Future progress will require sustained improvements in cancer prevention, screening, and treatment.

BACKGROUND: The American Cancer Society, the Centers for Disease Control and Prevention (CDC), the National Cancer Institute, and the North American Association of Central Cancer Registries (NAACCR) collaborate annually to provide updated information on cancer occurrence and trends in the United States. This year's report highlights brain and other nervous system (ONS) tumors, including nonmalignant brain tumors, which became reportable on a national level in 2004. METHODS: Cancer incidence data were obtained from the National Cancer Institute, CDC, and NAACCR, and information on deaths was obtained from the CDC's National Center for Health Statistics. The annual percentage changes in age-standardized incidence and death rates (2000 US population standard) for all cancers combined and for the top 15 cancers for men and for women were estimated by joinpoint analysis of long-term (1992-2007 for incidence; 1975-2007 for mortality) trends and short-term fixed interval (1998-2007) trends. Analyses of malignant neuroepithelial brain and ONS tumors were based on data from 1980-2007; data on nonmalignant tumors were available for 2004-2007. All statistical tests were two-sided. RESULTS: Overall cancer incidence rates decreased by approximately 1% per year; the decrease was statistically significant (P < .05) in women, but not in men, because of a recent increase in prostate cancer incidence. The death rates continued to decrease for both sexes. Childhood cancer incidence rates continued to increase, whereas death rates continued to decrease. Lung cancer death rates decreased in women for the first time during 2003-2007, more than a decade after decreasing in men. During 2004-2007, more than 213 500 primary brain and ONS tumors were diagnosed, and 35.8% were malignant. From 1987-2007, the incidence of neuroepithelial malignant brain and ONS tumors decreased by 0.4% per year in men and women combined. CONCLUSIONS: The decrease in cancer incidence and mortality reflects progress in cancer prevention, early detection, and treatment. However, major challenges remain, including increasing incidence rates and continued low survival for some cancers. Malignant and nonmalignant brain tumors demonstrate differing patterns of occurrence by sex, age, and race, and exhibit considerable biologic diversity. Inclusion of nonmalignant brain tumors in cancer registries provides a fuller assessment of disease burden and medical resource needs associated with these unique tumors.

BACKGROUND: The American Cancer Society, the National Cancer Institute (NCI), and the Centers for Disease Control and Prevention (CDC), including the National Center for Health Statistics (NCHS), provide the second annual report to the nation on progress in cancer prevention and control, with a special section on lung cancer and tobacco smoking. METHODS: Age-adjusted rates (using the 1970 U.S. standard population) were based on cancer incidence data from NCI and underlying cause of death data compiled by NCHS. The prevalence of tobacco use was derived from CDC surveys. Reported P values are two-sided. RESULTS: From 1990 through 1996, cancer incidence (-0.9% per year; P = .16) and cancer death (-0.6% per year; P = .001) rates for all sites combined decreased. Among the 10 leading cancer incidence sites, statistically significant decreases in incidence rates were seen in males for leukemia and cancers of the lung, colon/rectum, urinary bladder, and oral cavity and pharynx. Except for lung cancer, incidence rates for these cancers also declined in females. Among the 10 leading cancer mortality sites, statistically significant decreases in cancer death rates were seen for cancers of the male lung, female breast, the prostate, male pancreas, and male brain and, for both sexes, cancers of the colon/rectum and stomach. Age-specific analyses of lung cancer revealed that rates in males first declined at younger ages and then for each older age group successively over time; rates in females appeared to be in the early stages of following the same pattern, with rates decreasing for women aged 40-59 years. CONCLUSIONS: The declines in cancer incidence and death rates, particularly for lung cancer, are encouraging. However, unless recent upward trends in smoking among adolescents can be reversed, the lung cancer rates that are currently declining in the United States may rise again.

The fight against cancer escalated in 1971 with the introduction of the National Cancer Act during the presidency of Richard M. Nixon. Since that time, there have been dramatic developments in a number of research areas including prevention, screening, and treatment that have had a major impact on