CT-derived body composition predicts futile upfront resection in pancreatic cancer: a multicenter study.

purposeTo evaluate the utility of CT-derived body composition in predicting futile pancreatectomy and to develop a risk-stratification model for patients with pancreatic ductal adenocarcinoma (PDAC). MATERIALS AND

methodsPatients with anatomically resectable PDAC who underwent upfront pancreatectomy between March 2015 and November 2024 at three institutions were retrospectively included. Futile pancreatectomy was defined as death or recurrence within 6 months postoperatively. Body composition metrics were derived from skeletal muscle and adipose tissue segmented at the third lumbar level on preoperative CT, including the skeletal muscle index (SMI), deviation from sex-specific sarcopenia thresholds, and visceral fat-related ratios. A futility risk model was developed and validated using multivariable logistic regression, and its prognostic association with overall survival (OS) was assessed using Cox regression.

resultsA total of 604 patients (median age, 67.0 years [interquartile range, 60.0-72.0]; 348 males) were included, comprising 354 in the derivation cohort and 250 in the validation cohort. Futile pancreatectomy occurred in 20.2% of patients. Carbohydrate antigen 19-9, tumor size on CT, and SMI category, defined by relative deviation from sex-specific sarcopenia thresholds, were independent predictors and constituted the proposed futility risk model. In the validation cohort, the model achieved an area under the receiver operating characteristic curve of 0.750 (95% confidence interval (CI): 0.665-0.834) and was independently associated with OS after resection (HR, 1.53; 95% CI, 1.33-1.77; p < 0.001) after adjustment for pathological predictors.

conclusionsThe proposed model incorporating SMI predicts futile upfront resection in PDAC with moderate discrimination and provides preoperative prognostic information for OS. KEY POINTS: Question Can CT-derived body composition improve preoperative identification of patients with resectable pancreatic ductal adenocarcinoma who are at high risk of futile upfront pancreatectomy? Findings A model integrating CT-derived skeletal muscle index category, tumor size, and CA 19-9 achieved good discrimination for futile pancreatectomy and independently predicted overall survival. Clinical relevance By incorporating CT-derived skeletal muscle index category as an important patient-related factor, the proposed model for futile resection improves predictive performance and may help inform treatment sequencing between upfront surgery and neoadjuvant therapy in patients with pancreatic ductal adenocarcinoma.