Self-reported prevalence, etiology, and characteristics of pain in oncology outpatients

To determine the self-reported prevalence rates for cancer, non-cancer, and both cancer and non-cancer pain and to determine if there were differences in demographic, clinical, and pain characteristics among the three pain groups.

Patients were screened in outpatient oncology clinics for the presence of pain and/or analgesic use. Patients who reported pain completed the study questionnaires.

A total of 1790 patients were available for screening in the outpatient clinics and 1549 (86.5%) completed the screening questionnaire. Out of them, 332 (21.4%) reported pain or used analgesics. Of the 217 patients who completed the study questionnaires, 53% had only cancer pain (pain due to cancer and/or treatment), 25.3% had non-cancer pain, and 21.7% had both cancer and non-cancer pain. No differences were found, among the three pain groups, in pain intensity or pain duration. However patients in the cancer and non-cancer pain group had higher pain interference scores, higher severity scores for various pain descriptors, and a higher number of pain locations.

These findings suggest that outpatients with a combination of cancer and non-cancer pain may be at greater risk for under-treatment of pain. Oncology clinicians and primary care providers need to perform a comprehensive pain assessment of all oncology patients in order to be able to formulate an effective pain management plan.