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Background: The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial was initiated in 1992 to examine cause-specific mortality reduction from screening for these four cancers in men and women. We report lung cancer detection results of the baseline screening round., Methods: Of the 154,942 participants enrolled, who were aged 55-74 years with no history of PLCO cancers, 77,465 were randomly assigned to the intervention arm. Current or former smokers and never smokers in this arm received an initial single-view posterior-anterior chest radiograph., Results: In the initial screen, 5991 (8.9%, 95% confidence interval [CI] = 8.7% to 9.2%) of radiographs were suspicious for lung cancer: 8.2% (95% CI = 7.9% to 8.5%) for women and 9.6% (95% CI = 9.3% to 10.0%) for men. Rates were highest for older age groups and for smokers. Among those 5991 participants with a positive screen, 206 (3.4%, 95% CI = 3.0% to 3.9%) underwent biopsy examination, 126 (61.2%, 95% CI = 54.5% to 67.8%) of whom were diagnosed with lung cancer within 12 months of the screen (59 in women and 67 in men). The positive predictive value was 2.1% (95% CI = 1.7% to 2.5%), and 1.9 lung cancers were detected per 1000 screens. Among these cancers, 44% (95% CI = 35% to 52%) were stage I non-small-cell lung cancer. High rates of lung cancer were found in current smokers (6.3 per 1000 screens) and in former smokers who had smoked within the past 15 years (4.9 per 1000 screens). The lung cancer detection rate among never smokers was 0.4 per 1000 screens; this group accounted for 11% (95% CI = 5.6% to 16.6%) of the cancers identified., Conclusions: In the baseline screen, nearly half the cancers were stage I. Whether this experience results in a reduction in lung cancer mortality is yet to be seen.

Objective: To directly compare cancer incidence among Hispanic children and non-Hispanic white children in California and Florida, two states in the United States of America that include nearly one in three Hispanic children in the country., Methods: Cross-sectional data for 1988 through 1998 pertaining to all incident pediatric cancer cases (age < 15 years) with race/ethnicity coded as either Hispanic or non-Hispanic white came from the Florida Cancer Data System database and the California Cancer Registry database. The results were expressed as age-standardized incidence rates, standardized to the world standard million population. Hispanic rates and non-Hispanic white rates were compared using standardized incidence ratios (SIRs) with 95% confidence intervals (95% CIs.)., Results: The SIR for all cancers for Hispanic children compared to non-Hispanic white children was 1.02 (95% CI: 0.99, 1.05). For selected tumor types, SIRs indicated higher incidences among Hispanic children for leukemia (SIR = 1.26; 95% CI: 1.19, 1.34), Hodgkin's lymphoma (SIR = 1.29; 95% CI: 1.08, 1.54), and germ cell tumors (SIR = 1.62; 95% CI: 1.34, 1.96). There were lower incidences for the Hispanic children for central nervous system tumors (SIR = 0.72; 95% CI: 0.66, 0.78) and for sympathetic nervous system tumors (SIR = 0.76; 95% CI: 0.66, 0.87). In terms of interstate differences, the incidence of lymphoma, central nervous system tumors, sympathetic nervous system tumors, and malignant bone tumors was highest among Hispanic youth in Florida; the incidence of hepatic tumors was highest among Hispanic youth in California., Conclusions: While the overall cancer incidence rate among Hispanic children was similar to that for non-Hispanic white children, significant differences for specific tumor types were identified. Since Hispanic ethnicity may be a confounder for other cancer risk factors (e.g., familial, socioeconomic, or environmental), it is recommended that future research into Hispanic pediatric cancer risk investigate these risk factors.