A prospective study of the pathophysiology and clinical characteristics of pain in a palliative medicine population

Abstract

Comprehensive pain evaluation is requisite for optimal management. Few studies have evaluated pain syndromes and adequacy of associated analgesic regimens in one population. Available studies in cancer populations have focused on ambulatory patients or hospice-type inpatients. This study was designed to evaluate multiple characteristics of pain and adequacy of therapy in a broad spectrum of patients with advanced cancer presenting to a palliative medicine service. One hundred pain patients (95 with cancer) underwent a comprehensive pain evaluation consisting of history, physical examination, review of available diagnostics, and a pain assessment tool designed for routine clinical use. Seventy-one percent of 141 evaluable patients reported pain in the month before referral. In these 100 patients, 158 distinct sites of pain were reported, with 88 percent reporting a maximum of 2. Pain due to tumor was the most common cause (68 percent), and the most common pathophysiologic mechanism, somatic (52 percent). Pain was almost equally divided between continuous (48 percent) and intermittent (52 percent). Breakthrough pain occurred in 75 percent of continuous pains. Of these, 30 percent were exclusively incidental, 26percent nonincidental, and 16 percent due to end-of-dose failure. The remainder was of mixed etiology, but almost always with an incidental component. Of intermittent pain syndromes, 61 percent were incidental. On referral, analgesic dosing was inadequate and was compounded by use of regimens that typically did not meet peer-reviewed guidelines. Comprehensive studies rigorously evaluating characteristics of pain and response to treatment are a necessary first step toward more effective treatments for difficult pain syndromes.

Acupuncture: a treatment for breakthrough pain in cancer?

“…BTP is common in many cancer patients, particularly in those with bone metastases,21 and surveys show an incidence rate of between 50% and 89% 3 22–24. One study suggested that in more than half of patients experiencing BTP the flare-up was movement-related23 and this closely aligns with the findings of other investigators 1 24.…”

Epidemiology of Cancer Pain

“…A survey of 100 cancer patients with pain reported that pain was most commonly caused directly from the cancer itself ( Fig. 1) [3]. In this study, pain was most frequently reported as occurring in the chest, abdomen, and extremities (20% for each location).…”

Update in Cancer Pain Syndromes

“…Surveys of patients with cancer pain in hospitals, 6 hospices, 7 and palliative medicine clinics 8 tend to focus on descriptive aspects of pain rather than pain syndromes. Consequently, reports on the epidemiology of cancer pain syndromes reflect patients seen by pain specialists.…”