Delirium as a contributing factor to "crescendo" pain: three case reports.

Cancer patients occasionally experience periods of rapidly escalating pain--"crescendo" pain--that may present a challenge in assessment and management. Although these episodes are often associated with progressive neoplasm, any of a variety of other processes may be involved. Delirium is a potentially treatable and frequently unrecognized factor. We present three patients who illustrate this relationship between delirium and a crescendo pattern of cancer pain.