Medicine: Risks of Cancer

As part of the drive to improve cancer detection, 90 leading scientists met 14 months ago in Key Biscayne, Fla., under the auspices of the National Cancer Institute and the American Cancer Society, to identify individuals and groups who are most susceptible to cancer. Last week, in a 544-page volume titled Persons at High Risk of Cancer (Academic Press), they published their conclusions. They found that the occurrence of cancer seems to be influenced by a large variety of factors that fall into three broad categories:

ENVIRONMENT. A mass of evidence indicates that the...