Hi ucla2025,
I am glad to see you back, but I am sorry to hear that your husband needs chemo. Here is the link for the PC case where patient could not have radiation due to lesion location and had to have triplet treatment. Maybe this info can be of some help :
https://connect.mayoclinic.org/discussion/a-quandry-between-two-medical-recommendations-for-mpca-to-lung-only/
It was posted by @dpfbanks. She is very nice and kind lady and I am sure that she will be willing to help you with any particular question that you might have.

Wishing you and your husband the best of luck with new treatment and 100% success < 3.