Doctors in the study also appeared less likely to treat the pain of patients whose disease was considered mild or in remission, or if they were not undergoing chemo, radiation or surgery.
Fisch explains that the best and most aggressive pain management is usually delivered when the patient is visibly ill. Once the intervention is complete, pain management often falls by the wayside.
"Oncologists did well treating the sick cancer patient, but once the patient appeared to be doing better, that's when they were at the biggest risk to be undertreated," Fisch says.
But even when pain is apparent, heavy-duty pain drugs are not without a surplus of side effects -- a fact that can give both doctors and patients pause.
"Often you can't get away without taking a laxative to prevent constipation, or anti-nausea medicines to prevent that side effect," explains Glare. "People also worry if they can safely drive or use machinery at work." Some patients may out right refuse the medications for these reasons, others may take the prescription but never fill it out of fear of these side effects.
Insurance rules can also be an obstacle to connecting patients with the right medications. Glare says a lot of time is wasted getting prior authorization from insurance companies.
"In New York State for patients on Medicare, there is a very restricted list of pain medicines available without prior authorization," he said.
Other doctors say society's negative view of certain types of pain medications creates a major problem. Fears of overdose, overuse and addiction can make a patient hesitant to accept more powerful medications and doses.
"The current environment is more worried about the illegal use of controlled substances than the appropriate use," says Dr. Pam Kedziera, clinical manager for the pain and palliative program at Fox Chase Cancer Center in Philadelphia.
For Bennett, who says that she was at the lowest point of her life during the worst of her cancer pain, lifestyle changes including exercise, working with a nutritionist, acupuncture and meditation ultimately helped her take control of her pain.
"I started exercising, in small amounts, of course only 5 or 10 minutes at a time," she says. "I also used Tai Chi, which is good because it requires very little movement and more about breathing."
Based on her experience, she says she believes efforts to control cancer pain are misdirected and that others could experience more relief if exercise, nutrition and relaxation were "prescribed" along with the usual pills.
"The number one thing that keeps you out of pain is a positive attitude," she says. "It may sound like you are lying to yourself, but you find that it really brings you back to life."