Kate Johnson

August 30, 2012

August 30, 2012 (Milan, Italy) — More stringent screening and monitoring is recommended for cancer patients receiving opioid therapy for pain because of their risk for substance abuse, a new study suggests.

Researchers report finding evidence of addiction, including illicit drug use, double doctoring, and drug diversion, among a group of cancer patients.

Traditionally, cancer patients were not considered at risk for opioid or other substance abuse, given their short life expectancies, said the study's lead investigator Osama Alabdulhadi, MD, a neuroanesthetist at Dhahran Health Center in Dhahran, Saudi Arabia.

However, extended life expectancies in these patients have opened a window for greater risk for substance abuse, he told Medscape Medical News. "Although it's a small proportion of people, our recommendation is a careful psychosocial history and a careful family history, plus the urine test," he said.

Referral to a pain psychologist is perhaps the "best tool," Dr. Alabdulhadi added. "We recently started having our patients seen first by a pain psychologist, and this is very, very helpful to us. I would say it predicts at least 70% to 80% of patients at risk of becoming addicted."

Their findings were presented here at the International Association for the Study of Pain 14th World Congress on Pain.

Evidence of Addiction

In collaboration with the Pain and Symptom Clinic of the London Regional Cancer Program at the University of Western Ontario in London, Ontario, Canada, Dr. Alabdulhadi and his group prospectively followed 516 consecutive cancer patients (mean age, 62 years) between 2004 and 2010.

Risk factors for addiction and aberrant drug-related activities were documented, with a mean follow-up of 32 months.

Roughly half (53%) of the patients were female, and the mean maximal daily opioid dose was 426 mg in oral morphine equivalents.

Patients' tumor types included breast (n = 83), gastrointestinal (n = 80), lung (n = 79), urogenital (n = 79), other (n = 69), lymphoma (n = 45), multiple myeloma (n = 31), ear/nose/throat (n = 31), and skin (n = 19).

The primary pain diagnosis was tumor infiltration in 53% of patients, treatment-related pain in 34%, and pain unrelated to cancer in 13%.

Over the course of follow-up, patients were monitored with urine toxicology tests and interviews and were screened at baseline for family and personal history of substance abuse.

The study identified 46 patients (8.9%) who manifested at least 1 risk factor for substance abuse and 21 patients who manifested 1 or more behaviors "strongly suggestive of addiction," including illicit drug use (n = 13), ethanol abuse (n = 9), illicit double doctoring (n = 9), and drug diversion (n = 2).

For example, 2 patients tested positive for benzodiazepines when they had not been prescribed this medication, he said. In the case of ethanol abuse, this information was obtained from the patient or from the family.

Safeguards Needed

Asked to comment on the findings, Mark Sullivan, MD, PhD, said, "With increasing cancer survival, cancer pain management is becoming more like noncancer pain management. Treatment duration is longer, so more safeguards are needed."

In a separate plenary address on the subject of chronic opioid therapy in noncancer pain, Dr. Sullivan, who is professor of psychiatry and behavioral sciences and adjunct professor of bioethics and humanities at the University of Washington, in Seattle, acknowledged that the iatrogenesis of chronic opioid therapy has spread beyond medical boundaries into both social and cultural arenas, including "an erosion of our ability to handle pain in nonmedical ways, along with perhaps unrealistic expectations of relief."

Erica Weinberg, MD, a general practitioner in palliative care and pain management at Rouge Valley Health System, Toronto, Ontario, Canada, agreed that opioid misuse and substance abuse are growing problems among cancer patients.

"We're not doing enough," she told Medscape Medical News. "Clinicians treat cancer patients differently — they're very empathetic, they don't think there could be a problem, but I can't tell you the number of times I've had grandchildren stealing people's pills, and prescriptions getting 'lost,' and so forth — it's happening more and more. And patients are living that much longer."

In a recent publication on the subject, Dr. Weinberg writes, "Cancer patients and their families need to be screened for opioid misuse/abuse potential. This is important even in the end-of-life setting; diversion of opioids by families and friends is always a concern. Screen for chemical coping and emotional distress/mental health issues; treat appropriately with nonpharmacological and/or appropriate pharmacological means" (Hot Spot, the newsletter of the Rapid Response Radiotherapy Program of the Odette Cancer Center, August 2012).

"Do I screen every cancer patient that comes into the hospital? No," Dr. Weinberg said in an interview. "If they're going to stay in the hospital, I don't worry, but if they're going home again, where are their pills? It's the environment; it's screening the environment around them."


Neither speaker has disclosed any relevant financial relationships.

International Association for the Study of Pain 14th World Congress on Pain. Abstract PT 389. Presented August 28, 2012.