Interleukin-6, cortisol, and depressive symptoms in ovarian cancer patients

Inflammatory processes have been implicated in the pathogenesis of both depression and cancer. Links between depressive symptoms, interleukin-6 (IL-6), and cortisol dysregulation have been demonstrated in cancer patients, but vegetative versus affective components of depression have been minimally examined. The objective of the current study was to examine associations between IL-6, diurnal cortisol rhythms, and facets of depression in epithelial ovarian cancer patients.

Patients awaiting surgery for a pelvic mass suspected for ovarian cancer completed questionnaires, collected salivary samples for 3 days presurgery, and gave a presurgical blood sample. Ascites was obtained during surgery. IL-6 was measured by enzyme-linked immunosorbent assay and cortisol by a chemiluminescence immunoassay. The final sample included 112 invasive ovarian cancer patients (86 advanced stage, 26 early stage) and 25 patients with tumors of low malignant potential (LMP).

Advanced-stage ovarian cancer patients demonstrated elevations in vegetative and affective depressive symptoms, plasma IL-6, and the cortisol area under the curve (AUC) compared with patients with LMP tumors (all P < .05). Among invasive ovarian cancer patients, greater vegetative depression was related to elevated IL-6 in plasma (P = .008) and ascites (P = .024), but affective depression was unrelated to IL-6. Elevations in total depression (P = .026) and vegetative depression (P = .005) were also related to higher evening cortisol levels. Plasma IL-6 was related to greater afternoon and evening cortisol and cortisol AUC (all P values < .005).

These results demonstrate significant relationships between IL-6, cortisol, and vegetative depression, and may have implications for treatment of depression in ovarian cancer patients.