A cancer is not simply a lung cancer. It doesn't simply have a certain kind of appearance under the microscope or a certain behavior, but it also has a set of changes in the genes or in the molecules that modify gene behavior that allows us to categorize cancers in ways that is very useful in thinking about new ways to control cancer by prevention and treatment.
Harold E. VarmusIn general, all cancers have been traditionally characterized by the way they appear under the microscope and the organs in which they arise.
Harold E. VarmusThere are three great themes in science in the twentieth century : the atom, the computer, and the gene.
Harold E. Varmus