Development and validation of a predictive model for portal-systemic venous invasion grading in borderline resectable pancreatic cancer.

BACKGROUND

Portosystemic venous invasion (PSVI) depth critically influences prognosis in borderline resectable pancreatic cancer (BRPC), necessitating precise preoperative discrimination for personalized therapy.

AIM: To develop and validate a preoperative nomogram integrating computed tomography parameters and carbohydrate antigen 19-9 (CA19-9) kinetics for predicting PSVI depth in treatment-naive BRPC.

METHODS

This retrospective cohort study analyzed 167 BRPC patients undergoing radical resection between 2011 and 2023. Patients were stratified by pathological PSVI depth [no venous invasion (VI)/adventitial/muscularis propria/intimal]. Kaplan-Meier and ordinal logistic regression identified preoperative predictors from clinical/laboratory/computed tomography parameters (e.g., circumferential involvement and CA19-9). A nomogram was developed and validated via calibration curves/decision curve analysis.

RESULTS

PSVI depth significantly stratified survival.: Intimal VI showed worst prognosis (median overall survival: 9 months, 5-year overall survival: 0% vs no VI: 17 months, 12.5%; P < 0.001). Independent predictors: CA19-9 [odds ratio (OR) = 3.819, Wald = 14.125, 95% confidence interval (CI): 1.980-7.410], circumferential involvement (OR = 8.271, Wald = 33.352, 95%CI: 3.950-17.320), and luminal compromise (OR = 3.544, Wald = 8.489, 95%CI: 1.818-6.447). The nomogram achieved C-index = 0.928 (95%CI: 0.889-0.967), with 100-250 points indicating high invasiveness risk. Decision curve analysis confirmed clinical utility (threshold: 0-0.7).

CONCLUSION

This model integrates routine indicators to preoperatively quantify PSVI depth, guiding precision treatment.