SEATTLE — When Dr. Corey Casper started looking for doctors to team up with for his work on Kaposi’s sarcoma, the medical researcher at the venerable Fred Hutchinson Cancer Research Center ran into a surprising statistic from the World Health Organization.

He learned that Uganda has one of the highest rates of this type of cancer in the world. In fact, cancer in general kills more people in sub-Saharan Africa than AIDS, tuberculosis and malaria combined, according to the WHO.