Ever since the early 1930’s, an association between pancreatic cancer and depression has been noticed. The prevalence of depression is higher in patients with pancreatic cancer than it is in patients with other abdominal neoplasms, and psychiatric symptoms often precede somatic symptoms. Despite further research on this co-occurrence, the true mechanism of interaction is still not clear. Knowing what it is that forms the biological link between depression and the pancreatic tumour, could be of great importance to the future diagnostic and therapeutic workup of these patients.

Different theories are proposed. Plausible are the depression being induced through cytokines more specifically IL-6, alterations in the tryptophan-kynurenine, glutamate and serotonin pathways, and antibodies disturbing brain functioning directly or through serotonin. Depression causing cancer is also possible, but to date of unknown importance in pancreatic cancer. All this information brought together makes depressive symptoms of diagnostic importance in pancreatic cancer. The insights pave the way for the development of targeted therapies, hopefully to be implemented in clinical practice in the future.

(BELG J MED ONCOL 2017;11(5):212–217)