Thanks for your comments.
Radiation may be an option as it can reduce the Cancer growth, even if it
can't be removed. Also, know that there are various "grades" of cancer.
My mom's Lymphoma is what is termed as being "low grade" in that it is
very slow and non-aggressive.
Her Lymphoma can not be surgically removed given its precarious location
(in the right side of her grion, near vital nerves).
Radiation Theraphy was offered to her as an option.
However, given her age (she's 80) and her existing ongoing medical problems
(she's in remission after recently undergoing 12 cycles of chemotheraphy for
Hodgkin's Disease) she opted to forego Radiation.
Living with the Lymphoma and having it monitored, albeit untreated, her
oncologist said that she could concievably live another 10 years... which,
according to my mom is "... not bad for a messed up old lady..."
So, there are always options... and, there is always hope.
Best wishes to your dad.
My Cancer was in the Middle of my head and it could not be removed.
They can still do Chemo Therapy and maybe Radiation to shrink the tumour.
Stay Positive with your Dad. I'll light him a Candle and say a prayer. He has to be strong and so should you.