Philadelphia officials Wednesday announced the American Cancer Society will recruit volunteers for a nationwide, longitudinal study on cancer risk study at the May 6 Broad Street Run.

The group's cancer prevention studies are among the largest health studies of their kind in the world. They have enrolled more than 2 million people since the 1950s.

University of Pennsylvania cancer researcher Dr. Anil Rustgi, who is also affiliated with the ACS, said the first two taught the medical community much of what they know about cancer today.

"CPS I and II have been instrumental in our knowledge about the association of cigarette smoking with lung cancer, obesity with a variety of cancers, air pollution with lung disease and heart disease," Rustgi said.

The third iteration of the cancer study will, for the first time, look at genetic factors that could lead to cancer and will prioritize enrolling diverse participants.

"Much of what we know about what causes cancer we know from studies of primarily non-Hispanic, white individuals," said the study's national director Alpa Patel. "To understand how cancer affects different racial ethnic populations, we are aiming for at least a quarter of the population to be from other racial ethnic backgrounds."

The American Cancer Society usually signs up participants at Relay for Life races, but the group is having trouble meeting their minority enrollment target. This is the first enrollment push at a large, urban race such as the Broad Street Run.

Study participants must be between 30 and 65 years old and have no personal history of cancer. They will be asked to submit a blood sample, waist measurement, and survey when they sign up, and submit follow-up surveys for the next 20 to 30 years.