According to James Duke, a well-known published researcher of herbal medicine, (Handbook of Medicinal Herbs) papaya latex is prescribed in Cuba for cancerous growths.
Papaya latex is used in many industrial applications for food and drink for the active enzyme papain. Papain and its coenzyme chymopapain are active in the young papaya leaf and can be safely consumed as an herbal infusion or “tea”.
According to Shasta Darlington of CNN Health, “…Cuba has also developed a formidable biotechnology industry championed by Fidel Castro as early as the 1980s. Doctors here developed vaccines for Meningitis B and Hepatitis B which are now being used in a number of countries. Medical tourism is also on the rise, attracting paying patients from abroad.”
Interestingly, Cuba boasts a new drug for non-small cell lung cancer tumors called Cima-Vax EGF.