interferon vs chemo in lymphomatoid granulomatosis

my 29 yr old husband was diagnosed with grade 3 lymphomatoid granulomatosis...he has endured a round of r chop chemo and is now on the r ice chemo regiment. i recently found out about interferon as a possible treatment through my own research. he has had no luck with chemo and his dr. has not even mentioned interferon as a possible option .his prognosis is pretty poor so i am desperate for info from anyone who has endured both chemo and interferon therapy such as effectivness,side effects etc any feedback will be greatly appreciated

alisa