You might also contact the English Speaking Cancer Association in Geneva (ESCA). They will be familiar with the area, and various doctors.
www.cancersupport.ch
I know people who‘ve received treatment in Geneva, Lausanne, Sion, so there are good doctors, and almost all speak English. I don‘t know any specific doctors, though.
I received my treatment in Bern 8 years ago, and still return there for follow up. The care is excellent.
Wishing you a smooth transition and move.