In reply to oli1347:
> It's been my dad's dream to trek in Nepal for the past 50+ years and we're finally looking like it might be a possibility.
Go for it.
> Unfortunately he has some rather difficult health conditions including cancer.
> Just wondering if anyone has any recommendations for insurance companies that might cover him above 5000M and with complicated pre-existing conditions?
We used 'All Clear Insurance.' It wasn't cheap - but we got the holiday done.
Places like Macmillan, and Maggie's Centres, will be able to provide you with a list of possible providers.
Good luck. I hope you manage it.
Post edited at 21:17