This review examines the hypothesis that excess lung cancer risk in
worker cohorts exposed to asbestos occurs only among those with
asbestosis. The adequately designed studies in the literature support
this hypothesis. The summary relative risk for lung cancer was 1.00 in
seven cohorts with no deaths from asbestosis. In addition, there is a
high correlation between asbestosis rates and lung cancer rates in 38
cohorts in contrast to a poor correlation between cumulative exposure
data and lung cancer relative risks in eight cohorts with adequate
data. The evidence indicates that asbestosis is a much better predictor
of excess lung cancer risk than measures of exposure and serves as a
marker for attributable cases.
Abbreviations: CI = confidence interval;
f/mL = fibers per milliliter; mppcf = million particles (dust) per
cubic foot; RR = relative risk; SIO = small irregular opacities;
SMR = standardized mortality (or morbidity) ratio; SMSA = standard
metropolitan statistical area