Psychiatric morbidity and platelet monoamine oxidase activity in cancer patients.

Psychometric ratings for both anxiety and depression in 30 cancer patients were significantly elevated compared with values in 16 controls. The scores were especially high in the 14 patients who did not have breast cancer. This group also had significantly greater platelet monoamine oxidase activity than either the breast cancer patients or controls. Platelet monoamine oxidase activity values correlated significantly with both depression and anxiety scores in the whole cancer group.