[Scientific background of psycho-oncology]

We discussed the future direction of studies on psycho-oncology by reviewing relevant previous findings regarding treatment, early detection, and prevention of psychiatric disorders experienced by cancer patients. PSYCHIATRIC DISORDERS IN CANCER PATIENTS: It is reported that the common psychiatric disorders among cancer patients are adjustment disorder, major depression, and delirium. In addition, prevalence of adjustment disorder and major depression is higher among advanced cancer patients than that among patients with early stage cancer, and that delirium is the most common disorder among patients with terminally ill cancer.

Some meta-analytical studies reveal an effectiveness of psychotherapy for anxiety and depression among cancer patients however, several systematic reviews do not. Three randomized clinical trials indicate the efficacy of pharmacological treatments, anti-depressants, for major depression in cancer patients. It is suggested that delirium in advanced/terminally ill cancer patients can be ameliorated by detection and management of underlying causes of delirium and concurrent symptomatic treatment such as pharmacotherapy. EARLY DETECTION: Several brief screening instruments have been developed to detect adjustment disorder, major depression, and delirium among cancer patients.

One randomized clinical trial indicates the efficacy of SSRI for preventing depression occurring after interferon therapy among patients with malignant melanoma. No other effective strategy for prevention of psychiatric disorders among cancer patients has been clarified.

There are not enough findings for effective treatments for ameliorating the common psychiatric disorders experienced by cancer patients, and very few studies for prevention while there are several available findings regarding early detection of their psychiatric disorders. Thus future studies on developing novel treatments including prevention and studies on mechanism should be encouraged. Psycho-oncology group in National Cancer Center are now conducting several clinical studies such as biological studies (neuro-imaging studies), studies to establish novel treatment strategy (n-3 poly unsaturated fatty acid), and multi-faceted intervention study (screening and individually tailored psychotherapy and pharmacotherapy).