Depression and cancer.

Depression appears to be a frequent complication of neoplastic disease. Recent surveys suggest that it is not only a common reason for psychiatric referral but that a substantial minority of hospitalized cancer patients suffer from an affective disturbance severe enough to warrant psychiatric intervention. In view of its reported prevalence it is likely that this complication adversely affects the quality of patients' lives and interferes with the management of their disease. Given the nature of this problem it is disturbing that so little systematic research has been done, especially in the area of treatment. In this article we critically review the literature concerned with the relationship of depression to cancer. We begin with comment on the nature of the association between cancer and depression and the question of whether depression is an etiologic factor in neoplastic disease. Before considering the prevalence of affective disorders among cancer patients, we examine the difficulty of diagnosing depression in seriously ill patients. Next, we explore the role of various psychological and biological factors in the etiology of this complication and, finally, we offer recommendations for treatment and suggest directions for future research.