While seeking help/information from a doctor that is up to date with the science on vaping is the best course of action in this case I can give you some relevant information.
The only possible interaction I could see is if you have an allergy to propylene glycol which affects a very small percentage of vapers and can cause nausea which could worsen the side effects of treatment, but like I said this only affects a small percentage of people and can be avoided by using max VG eliquid.
As for the relative risk of smoking versus vaping a more recent study showed that vaping only has around 1% the cancer risk that cigarettes have so it may be a good move to make the switch however I am not a doctor and don't feel comfortable giving medical advice, I'd really suggest talking to your doctor about this or one that is up to date on the science surrounding vaping.