LSS Report 12: Supplementary Tables This document describes supplementary tables summarizing site- specific cancer mortality data for the Life Span Study (LSS) during the period from October 1, 1950 through the end of 1990. The primary analyses and discussion of these data are given in Part 1 of LSS Report 12. In addition to these tables, RERF has released two datasets that provide detailed stratification of these mortality data by city, sex, organ (colon or marrow) dose, age at exposure, and time since exposure. The results presented herein are based on organ- dose-specific tables of cases and person years. The tables are included in an Excel 7.0 worksheet file called R12Supp.xls. Three tables are presented for each of the cancers or groups of cancers listed in Table 1. The last two tables in each set summarize the distribution of the observed and expected numbers of cases together with person-years by dose and time period or age at exposure categories. These tables also indicate the total number of people by dose category and sex. The expected numbers of cases in each table were computed on the basis of a stratified excess relative risk (ERR) model that was linear in dose and allowed for age-at-exposure and, where relevant, sex effects on the ERR. Expected numbers of cases are computed from the stratified background model, with stratification on city, sex, age at exposure, and attained age. The ERR estimate is simply observed divided by expected minus one. Table 1: Cancers used in supplementary tables Cancer / ICD codes Organ dose Cancer Group (9th Rev) Solid cancers 140 - 199 colon Leukemia 204 - 208 bone marrow Stomach 151 stomach Lung 162 lung Liver 155 (0, 1, 2) liver Colon 153 colon Rectum 154 bladder Pancreas 157 pancreas Esophagus 150 bone marrow Gallbladder 156 liver Bladder 188 bladder Uterus 179 - 182 uterus Female breast 174 breast Ovary 183 ovary Prostate 185 bladder Other Solid all other colon Cancers codes between 140 and 199 Malignant 200-202 bone Lymphoma marrow Multiple 203 bone Myeloma marrow The first table in each set presents parameter estimates and the results of selected hypothesis tests for the site. With the exception of the test for a non-linear dose response, which is based only on those people with DS86 shielded kerma estimates of less than 4 Gy, these estimates and tests are based on analyses of all LSS for whom DS86 doses have been computed. Detailed results for both excess relative and excess absolute risk models are presented for sites for which the number of cases was large and there was evidence of a radiation-related excess risk. For other sites parameter estimates and hypothesis tests were carried out for a limited number of factors only for ERR models. Models used for analyses and hypothesis tests The ERR analyses were based on stratified background models. The stratification variables were city, sex, age at exposure, and attained age. In the more detailed analyses the basic model for the ERR was linear in dose with sex and age at exposure as modifying factors. This ERR used in this model can be written as: ERR = b d exp ( b (e - 30)) 1s 2 where b is a sex-dependent dose effect and b represents the effect 1s 2 of age at exposure (e). Because of the way in which e appears in the model, the dose effect parameters correspond to the risk for a person who was 30 years of age at exposure. The effect of attained age on the ERR was examined by adding term that is linear in log attained age to the exponential term in the above model. In looking at city effects, it was assumed that the effect would be the same for men and women. In those sites for which the number of excess cases was insufficient to allow working with the full model, neither age-at-exposure nor sex effects were routinely included in the models. With the exception of breast cancer, excess absolute risks were modeled relative to a fully parametric model for the background risks. Under the model the logarithm of the background risks was described as a sex-specific quadratic spline in log attained age with a single knot at age 70. The intercept in this model was allowed to depend on sex, city, and year of birth. Background risks for breast cancer were modeled in terms of a log-linear spline in attained age with a single knot at age 50. The intercept was allowed to depend on city and birth cohort. The basic model used for the excess absolute risk is EAR = b d exp ( b ln(age/50)) 1s 2 where age is attained age and thus the sex-specific dose coefficients describe the risk at age 50. Technical notes on hypothesis tests and confidence intervals In most cases hypothesis tests are based on likelihood ratio tests and confidence intervals were computed by direct evaluation of the profile likelihood. However, there are situations in which it is not possible to compute the likelihood ratio statistic or, somewhat more often, likelihood- based confidence bounds. These situations arise when the dose effect is negative for some subset of the population either at the maximum likelihood estimate or at some point in the confidence region for the parameter of interest. If the MLE did not exist the score test was used. Cases in which confidence bounds could not be computed are indicated as N.C. in the tables. A related problem occurs in the computation of confidence intervals for ratios of effects (i.e. sex and city effect ratios). If the joint confidence interval for the numerator and denominator includes 0 for both effects, all values of the ratio are consistent with the data. This is indicated by the phrase 'all values' in the tables. If the joint confidence interval includes 0 for the denominator but not the numerator, the confidence interval for the ratio consists of all points outside of some interval. In such cases we report only the upper interval indicating a positive lower bound and an infinite upper bound (indicated as inf in the tables.). In most cases the negative interval cannot be computed for the models that we consider. Copyright 2003. Radiation Effects Research Foundation