April 13 (HealthDay News) -- Race and genetics may not be as big a factor in surviving certain cancers as long suspected, a new study finds.
Though racial disparities have been found in many studies, researchers say they are far less apparent when zeroing in on smaller populations or geographical areas, such as a neighborhood instead of a city.
A report in the May 15 issue of Cancer suggests that this means that modifiable factors -- such as socioeconomic situations, stages of the cancer, treatment and other aspects of a person's health -- might play a bigger role than biology in determining survival from a tumor.
In the report, led by Jaymie Meliker, an assistant professor of preventive medicine at Stony Brook University in New York, researchers reevaluated information that whites in southern Michigan had far better survival rates than blacks when diagnosed with breast or prostate cancer. The gaps often were negligible -- and sometimes completely disappeared -- when the population or geographic focus narrowed from large counties to just cities, towns or neighborhoods, the study found.
"When racial disparities vanish in small geographic areas, it suggests that modifiable factors are responsible for apparent racial disparities observed at larger geographic scales," the authors wrote.
The study did not delve into the relative impact of different modifiable factors but did suggest that genetic factors probably were not key determinants in survival differences.
SOURCE: American Cancer Society, news release, April 13, 2009