With the support of the SCEHSC and NIEHS, the USC Norris Comprehensive Cancer Center, and the American Cancer Society, a book, Cancers in the Urban Environment, describing the patterns of cancer in Los Angeles County by census tract during the period 1972-98 appeared early in 2004. Assembled and written by Dr. Thomas Mack, 84 different malignancies are described, including 72 uniquely defined by histological and anatomical criteria, and 12 categories defined by age at diagnosis or organ site. Following a brief introduction and guide to interpretation, each set of graphics includes, separately for males and females, a comparison between incidence rates in Los Angeles County and other populations, a time trend, age-specific incidence by race/ethnicity, and a comparison by social class. Those census tracts with a standard incidence ratio of at least 1.5, and falling above the 95% Poisson upper confidence limit, are identified and characterized according to the magnitude, time trend, and sex-concordance of the high incidence. These tracts are described in maps, before and after adjusting for social class. It is hoped that this book will help laypersons better understand the patterns of cancer occurrence and help address concerns about local cancer rates, and will enable investigators to concentrate on those patterns unexplained by available etiological information.

An important inter-Core paper was published in 2004 by investigators in the Respiratory Effects, Exposure Assessment, and Study Design Research Cores. Longitudinal findings from the Children's Health Study (CHS) (Gauderman et al., 2004), were described in "The effect of air pollution on lung development from 10 to 18 years of age." In this prospective study, we recruited 1759 children (average age, 10 years) as part of the CHS from schools in 12 southern California communities and measured lung function annually for eight years. The study communities represented a wide range of ambient exposures to ozone, acid vapor, nitrogen dioxide, and particulate matter and included some of the most polluted areas in the greater Los Angeles basin, as well as several low-pollution sites outside the area. We examined the relationship of air pollution to the forced expiratory volume in one second (FEV1) and other spirometric measures. Over the eight-year period, deficits in the growth of FEV1 were associated with exposure to nitrogen dioxide, acid vapor, particulate matter with a diameter of less than 2.5 micron (PM2.5), and elemental carbon, even after adjustment for several potential confounders and effect modifiers. Associations were also observed for other spirometric measures. Exposure to pollutants was associated with clinically and statistically significant deficits in the FEV1 attained at the age of 18 years. For example, the estimated proportion of 18-year-old subjects with a low FEV1 (defined as a ratio of observed to expected FEV1 of less than 80 percent) was 4.9 times as great at the highest level of exposure to PM2.5 as at the lowest level of exposure. The results of this study indicate that current levels of air pollution have chronic, adverse effects on lung development in children from the age of 10 to 18 years, leading to clinically significant deficits in attained FEV1 as children reach adulthood. The potential long-term effects are likely to be very significant and the regulatory and public health implications of this study are clear as the effects followed a dose-response pattern.

Another important inter-core collaboration (Study Design and Cancer Research Cores) was achieved in 2004. Dr. Siegmund and colleagues devised a statistical method for the analysis of clustered methylation, to be used in connection with the MethylLight technology (Siegmund et al. 2004). The methodology was then applied to breast cancer patients in relation to hormone receptor and tamoxifen status (Siegmund et al. 2004), to apoptosis associated genes from bladder cancer patients (Siegmund et al. 2004), and to lung cancer patients in relation to smoking (Siegmund et al. 2004). This methodology expands the potential of the Cancer Research Core to study environmental factors in conjunction with methylation patterns and cancer risk.