Comprehensive Summary
This study by Shen et al. examines whether inflammatory biomarkers can be used with machine learning (ML) models to identify depression in pancreatic cancer patients. Researchers assessed 328 pancreatic cancer patients using the Patient Health Questionnaire-9 (PHQ-9) and collected routinely available clinical and inflammatory biomarker data, including C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and albumin. Four machine learning models (logistic regression, random forest, support vector machine, and extreme gradient boosting) were trained on 70% of the data and evaluated on the remaining 30% to predict clinically significant depression. Generalized estimating equations (GEE) were also used to analyze the associations between inflammatory markers and depression. The machine learning models showed moderate but consistent predictive performance with AUC values ranging from 0.70 to 0.72. Permutation importance analysis identified CRP, NLR, and albumin as the most significant predictors of depression. GEE analysis confirmed that elevated levels of CRP and NLR were independently associated with a higher likelihood of depression. The findings suggest that inflammatory markers are moderately but significantly correlated with depression in pancreatic cancer patients and that ML can effectively use these markers to predict depression. This also supports the linkage between depression and inflammation.
Outcomes and Implications
This research is important because depression is highly prevalent in pancreatic cancer patients and is linked to worse quality of life, treatment adherence, and survival, yet often goes under-diagnosed. Identifying objective biomarkers to predict depression could complement or even substitute for questionnaires that many patients may not complete. Clinically, incorporating routine inflammatory biomarkers into ML algorithms could provide a low-cost, scalable, and automated way to screen for depression risk during standard cancer care. Although current model accuracy is moderate and not yet sufficient for clinical deployment, the approach demonstrates strong potential for integration into electronic health records. With larger, multi-center validation, such models could be implemented to support real-time depression monitoring and prompt early psychiatric referral in oncology practice, easing the burden on both patient and physician.