@nancyd823
In my case - nasopharyngeal cancer - i.e. cancer at the back of nose - my family doctor referred me to a doctor in Toronto General Hospital (part of the UHN network) who did tests and when diagnosed with nasopharyngeal cancer, I was referred to PMCC, UHN.
Since your dad is lung cancer - perhaps you may want to check if your doctor can refer your dad to the appropriate doctor in PMCC for tests / treatment.
Best wishes !!!