Being poor, living in inner-city neighborhoods and having little education have more to do with the high rates of cancer among blacks than does race, a National Cancer Institute study says.

In a report published in the NCI Journal, specialists adjusted statistical data to isolate the effects of poverty, population density and education on the incidence of cancer.Statistician John W. Horm said the figures showed that race played less of a role in overall cancer risk than did the other factors.

In earlier studies that compared the races only, blacks had a 6 to 10 percent greater overall cancer risk than whites, and more than a 20 percent greater risk for specific types of malignant disease, such as lung cancer.

The new study used data from three cities - San Francisco, Detroit and Atlanta - and correlated cancer incidence with data from the 1980 census.

Cancer incidence data were adjusted so that whites and blacks of similar socioeconomic status were compared. The study found that on this basis, the rates for whites went up, both for overall cancer risk and for three of the specific sites of malignancy - rectum, lung and female breast.