Many people with colon cancer or lung cancer continue to smoke after being diagnosed, researchers say. They emphasize the need for cancer specialists to recommend that people quit and give them help to do so.

The U.S. Centers for Disease Control has launched a $54-million U.S. television advertising campaign aimed at shocking smokers into quitting.

Nicotine replacement therapy, including patches and gum, don't seem to help people quit smoking in the long-term, researchers say.