Depression as a multidimensional host factor and oncologic outcomes in breast and gynecologic cancers: A narrative review.

Depressive disorders and clinically significant depressive symptoms are common in women with breast and gynecologic cancers, although prevalence estimates range from approximately 12% to more than 50% depending on instrument, threshold, timing, and setting. This narrative review, structured according to SANRA criteria, examines evidence on depression and oncologic outcomes in breast and gynecologic cancers and grades each claim by type and strength of evidence. Meta-analyses of observational studies consistently associate depression with recurrence and with cancer-specific and all-cause mortality (pooled relative risks of approximately 1.2-1.3 in breast cancer), and with lower adherence to adjuvant endocrine therapy and radiotherapy. These are prognostic associations; residual confounding by stage, symptom burden, comorbidity, socioeconomic disadvantage, and access to care, and reverse causation, cannot be excluded. Neuroendocrine, inflammatory, and immune mechanisms are best characterized in ovarian cancer, largely in preclinical models and often in relation to chronic stress rather than clinical depression, and whether depression modifies the efficacy of immune checkpoint inhibitors in gynecologic cancers has not been studied. No adequately powered trial has tested whether treating depression improves cancer outcomes; available data come from broader psychosocial interventions and secondary analyses. We propose the Women's Biobehavioral Oncology Framework, an unvalidated conceptual model distinguishing depression as a prognostic marker, a possible causal contributor, and a treatment target, and a prioritized research agenda. Screening and treatment of depression are justified on clinical grounds; its use for risk stratification or treatment selection requires prospective validation.