Welcome to the forum. All I can give by way of advice is that there are a lot of people making tons of money claiming to have a cure for cancer, so be very careful. Best to follow the professionals' advice and at 75, being otherwise in decent health, he can have many cancer free years ahead. My mother, 87 years old, is a 20 year survivor of breast cancer. Please encourage him to do what it takes. It' awfully tough but life is worth it.

David R. 65 yr old male non-smoker, light drinker, stage 3 or 4, depending on which doc you ask, scc rt. tonsil, 2 nodes, 7 weeks radiation and chemo. No surgery. Teatment ended 3/20/08. PET scan 8/08 showed no cancer.
And now, as of oct, 2010, caregiver to wife, Linda, with breast cancer.
May, 2013, Linda diagnosed with stage 3 ovarian cancer. Enuf already.