NEW YORK (AP) — Most patients getting chemotherapy for incurable lung or colon cancers mistakenly believe that the treatment can cure them rather than just buy them some more time or ease their symptoms, a major study suggests. Researchers say doctors either are not being honest enough with patients or people are in denial that they have a terminal disease.

The study highlights the problem of overtreatment at the end of life — futile care that simply prolongs dying. It’s one reason that one quarter of all Medicare spending occurs in the last year of life.