Pathophysiology of depression in cancer patients

Abstract

Roughly half of the Japanese population experiences cancer, a distressful experience which can be accompanied by depression. In this review, we compare findings from studies on the pathophysiology of depression in cancer patients with findings from studies of depressed individuals without cancer. Several neuroimaging studies of depressed cancer patients found that parameters such as hippocampal volume and subgenual anterior cingulate neural activity were similar to those in depressed individuals without cancer. In contrast, levels of biological markers derived from blood samples such as interleukin-6, brain-derived neurotrophic factor, and omega-3 fatty acids in depressed cancer patients differed from those in physically healthy depressed individuals. These differences may suggest that the pathophysiology of depression in cancer patients also differs from that of physically healthy depressed individuals. Given the variety in cancer type, clinical stage, and treatment, the pathophysiology for depression among cancer patients may also vary widely by patient. Further studies are needed to elucidate the pathophysiology of depression in cancer patients.