The incidence of pain, depression, and delirium all increase with higher levels of physical debilitation and advanced illness (Burkberg, Penman, and Holland, 1984). Approximately 25 percent of all patients with cancer experience severe depressive symptoms, with the prevalence increasing to 77 percent in those with advanced illness (Burkberg, Penman, and Holland, 1984). Among patients with cancer, the prevalence of organic mental disorders (delirium) requiring psychiatric consultation has been found to range from 25 to 40 percent and to rise to as high as 85 percent during the terminal stages of illness (Massie, Holland, and Glass, 1983).
Psychiatric symptoms in patients with pain should be viewed initially as a possible consequence of uncontrolled pain. Mood as well as personality characteristics may be distorted by the presence of uncontrolled pain, and relief of pain may often result in the disappearance of a perceived psychiatric disorder (i.e., anxiety or depression) (Ahles, Blanchard, and Ruckdeschel, 1983). The patient's mental status should be reassessed after pain has been controlled to determine if a psychiatric disorder is present. The management of specific disorders such as depression, delirium, and anxiety in patients with cancer has been reviewed in detail elsewhere (Breitbart and Holland, 1988; Holland and Rowland, 1989).
Assessment of Common Cancer Pain Syndromes