My beloved brother has stage 4 stomach cancer

two weeks ago my brothers CT scan showed he has stage 4 stomach cancer spreading to abdomen, from a strapping 14 stone he had dropped to well below 10 stone, Drs have put a stent in his liver, drained his stomach of 7 litres & now it's bloating again & they don't want to do it again, they want him to accept DNR & we don't want to know how long he's got left , this is all new to us & beyond devastating,he's the one who kept the family together & he's only 44, we never knew such suffering could befall anyone, I don't want to lose him