Because that is the only way to discover new drugs to face the different types of cancer that continue to destroy lives and overburden socially and financially the society as a whole.
There is initially a lab research, during which the scientist works in a lab, developing and testing drugs to manufacture medicines to cure diseases. Such initial process usually takes 10 years before any test is carried out in human beings.
And there is a clinical trial when the drug is tested in human beings.
Through the researchers, the physicians find new and better ways to help the civil society to prevent, diagnose, control and treat diseases.
An example of that is the great progress of cancer treatments along the last 50 years, benefitting everyone. That disease used to be a sentence of death and suffering, however, today we can see new horizons: the physicians are curing a continuously increasing number of patients – and mainly, improving their quality of life. Nevertheless we still need to do a lot, generate additional knowledge and develop more effective drugs, additional knowledge and develop new drugs to address the huge challenge posed by cancer, especially those types associated with specific geographies or populations, which are not addressed by worldwide researches.