Do you think that there is a mutated gene for every cancer out there and its just a matter of finding the switch to turn it off like they have been able to do with ALK and BCR.ABL, and Hh?
No - examples like ALK and BCR/ABL are the exceptions rather than the rule. In most cancers there is a lot more going on than a single gene stuck in the "on" position.
But you might yet see more magic with the right combination therapy in these more complex cancers.