This is from a news article :
As years went by, some researchers began to wonder if radiation was still necessary. Chemotherapy, surgery and medical imaging had improved, and patients were being diagnosed earlier, before their cancer was as advanced.
"As" seems to be an adverb meaning 'to the same degree or amount' in this context so I think 'as to require radiation' is omitted after "as advanced" in this context.
Am I right?