Even though smoking is a risk factor for multiple types of cancer, more than half of smokers diagnosed with the disease keep using tobacco, and doctors aren't doing enough to help them quit.

A West Virginia University survey published in the Journal of Oncology Practice found that 44 percent of smokers quit after being diagnosed with cancer.

Less than two thirds, 62 percent, say they received advice from doctors or nurses about quitting the habit.

Dr. Jame Abraham, the study's lead author, says the survey shows there's a need for intervention programs to help cancer patients quit tobacco.

In addition to being a risk factor for cancer, smoking can complicate common cancer treatments like surgery and radiation therapy.