History of psycho-oncology: overcoming attitudinal and conceptual barriers.

The formal beginnings of psycho-oncology date to the mid-1970s, when the stigma making the word "cancer" unspeakable was diminished to the point that the diagnosis could be revealed and the feelings of patients about their illness could be explored for the first time. However, a second stigma has contributed to the late development of interest in the psychological dimensions of cancer: negative attitudes attached to mental illness and psychological problems, even in the context of medical illness. It is important to understand these historical underpinnings because they continue to color contemporary attitudes and beliefs about cancer and its psychiatric comorbidity and psychosocial problems. Over the last quarter of the past century, psycho-oncology became a subspecialty of oncology with its own body of knowledge contributing to cancer care. In the new millennium, a significant base of literature, training programs, and a broad research agenda have evolved with applications at all points on the cancer continuum: behavioral research in changing lifestyle and habits to reduce cancer risk; study of behaviors and attitudes to ensure early detection; study of psychological issues related to genetic risk and testing; symptom control (anxiety, depression, delirium, pain, and fatigue) during active treatment; management of psychological sequelae in cancer survivors; and management of the psychological aspects of palliative and end-of-life care. Links between psychological and physiological domains of relevance to cancer risk and survival are being actively explored through psychoneuroimmunology. Research in these areas will occupy the research agenda for the first quarter of the new century. At the start of the third millennium, psycho-oncology has come of age as one of the youngest subspecialties of oncology, as one of the most clearly defined subspecialties of consultation-liaison psychiatry, and as an example of the value of a broad multidisciplinary application of the behavioral and social sciences.