The report clearly demonstrates that there are identifiable geographic patterns of cancer mortality in the 49 counties comprising the New York-New Jersey-Philadelphia metropolitan region. This indicates that specific factors are involved, which are potentially identifiable through further research. Many such factors were investigated, and a number of them, related to both high and low risk, were evaluated and described. There are some factors which appear more often than others: degraded air quality, ethnic background, the presence of workers in certain industries, socioeconomic level, the source of drinking water, motor vehicle traffic and diet, in particular. Because of the fact that the data used were available only at the county level, and because some of the data were more complete and sound than others, the strength of the statistical correlations derived from the data varied. In brief, the study does not point to any one factor or group of factors as being 'responsible' for the high cancer mortality rates in this region. Rather, it presents a number of high and low risk factors, and points to those which need to be evaluated in much greater detail.