is it necessary to study physics in high school to be paediatric oncologist?
You should look at the requirements for the schools you are interested in.
Programs vary from state to state and of course country. If you have 10
or more schools picked out you may want to choose your college courses
so that you will meet the prereq requirements for all of them. You may find
Physics 101 to be a nice diversion from Biology and Chemistry courses. It may
also help you to conceptualize gas exchange, ion transfer, range of motion,
bone fractures and healing etc.