(HOUSTON) -- As many as one-third of cancer patients may be receiving inadequate treatment to control their pain, even though many medicines are available to help, new research suggests.
Pain is one of the most-feared and worst symptoms of cancer. As disease progresses, pain can become completely debilitating for cancer patients.
Dr. Michael Fisch, lead author of the study and chair of the department of general oncology at MD Anderson Cancer Center in Houston, said he undertook the research to get a better grasp on how many cancer patients need pain control and assess the current methods.
"We didn't understand enough about how people are being treated," he said.
In the largest U.S. study of its kind to date, Fisch and his colleagues looked at more than 3,000 patients for over a month who suffered from invasive cancerous tumors of the breast, prostate, lung, colon or rectum. The patients, who were undergoing treatment at 38 different medical institutions, completed a 25-question survey, and researchers recorded the medications they were taking.
The researchers then determined the adequacy of the patients' pain management using a scale that compared the patient's symptoms of pain to the strength of medication they were taking.
At the start of the study, two-thirds of patients required medication to manage their pain. The researchers found that of these patients, one-third were taking insufficient medications to control the pain they were experiencing.
Thirty days later, when they repeated the questionnaire and examination of the patients' medications, the situation had not improved; the percentage of patients who reported that their pain was undertreated was roughly the same.
"Past studies just looked at one snippet in time, so we wanted to see if improvements are made once the patient has good follow-up," says Fisch. "This shows there is still work to be done,"
Surprisingly, physicians in the study were aware of the problem; in fact, for decades, doctors across the country have been aware that undertreated pain among cancer patients is a problem that needs to be addressed.
Given the constantly changing and progressing symptoms of cancer, doctors say that managing the associated pain can be difficult. What may be successful pain management for a cancer patient on one day may not suffice the next. Or the medication could become more than needed.
In the study, about 30 percent of the patients who were initially undertreated did gain control of their pain over the month-long study. But 10 percent of the patients who were originally treated appropriately lost control over their pain by the follow-up visit.
Another problem that doctors face is objectively determining how much pain a patient is actually experiencing. The commonly asked pain assessment question -- "What is your pain on a scale of one to ten?" -- often does not paint a complete picture, doctors say.
Copyright 2012 ABC News Radio