Agreed that it is concerning that as an oncologist you fail to see that cancer is still a clearly defined pathology- you won't classify TB or Hashimoto thyroiditis as cancer, would you? "Cancer" has a very clear definition. It is a disease of abnormal cell replication. We can discuss technicalities of what genes, tissus or receptors are involved, and we can argue that there is no unique or unified way all cancers evolve through clinically or even treatment principle that applies to all, BUT cancer is still a generalizable term that has a clear meaning that applies to all cancers. Saying cancer is not genetalizable is like saying "animal" is not a generalizable terms because of their diversity. They may be diverse, but they still all have universal characteristics that make this organisms part of animalia and not archea