Temporal presentation of chronic cancer pain: transitory pains on admission to a multidisciplinary pain clinic.

Transitory flares of pain are well-recognized events in both untreated and treated patients suffering from chronic cancer pain. For the purpose of this survey, we refer to transitory pain (TP) as any event subjectively characterized by transience and pain intensity over a baseline pain. In Part I, TP was reported by 243 (39%) of 613 consecutive cancer pain patients. Gender, age, tumor site, stage, and therapy were not related to the presence of TP. Neuropathic baseline pain was associated with a higher prevalence of TP (P < 0.0001). TP was somatic in 39%, visceral in 22%, and neuropathic in 36% of patients. TP intensity was severe or worse in 92% of patients. Neuropathic TP was briefer and occurred more frequently than nociceptive TP. In Part II, further features of TP were surveyed in 55 patients. Patients reported spontaneous occurrence of TP (40%), a relationship to movement (36%), to the analgesic regimen (35%), to coughing (11%), and to various other factors (18%). Only half of the movement-related TP were predictable. Rescue medication was at least partially effective in 75% of patients. Change in position, rest, diversion, and physiotherapy were commonly employed to alleviate TP. This survey outlined a framework to characterize TP that may prove useful to clarify the definition, pathophysiology, and prevalence of these pains.