A First Scoring System With Radiological Parameters To Predict Prognosis In Pancreatic Cancer After Pancreatectomy Plus Venous Reconstruction

Background:Pancreatic cancer is mainly diagnosed at an advanced stage when adjacent vessel invasion is present.However,the conventional computed tomography(CT)criteria mainly focus on the evaluation of vessel invasion but less on the outcome of patient evaluation.We address this issue by establishing an effective prognostic nomogram with radiological parameters for pancreatic carcinoma after pancreatectomy plus venous reconstruction.Methods:Primary data were derived from 266 patients who received pancreatectomy and venous reconstruction confirmed pancreatic cancer in 4 academic institutions from January 2012 to June 2016.According to a ratio of 3:1,201 patients were divided into model group,and the other 65 patients were divided into validation group randomly.Only the demographic parameters and radiological parameters were evaluated using univariate and multivariate Cox regression analyses.The final nomogram was evaluated by Harrell's concordance index(C-index),calibration curve and validated by 65 patients included in the validation group.Vascular abnormalities in radiological parameters were classified into type 1-4 by computed tomography and included into the nomogram.The pathological correlation of radiological parameters was analyzed by Chi-square test.Results:Age(P = 0.002),length of tumor contact(P = 0.016)and vascular abnormalities(P<0.001)were independent factors for survival.The nomogram had a good calibration curve for probability of survival.The C-index of the model for predicting overall survival(OS)was 0.811 and 0.800 for model and validation cohorts,respectively.Seven image features(absent,mild deformity,tear drop,tethering,stenosis>1/2,obstruction and embolus)of vascular abnormalities were confirmed and classified into Type 1(absent),Type 2(mild deformity or tear drop),Type 3(tethering or stenosis>1/2)and Type 4(obstruction or embolus)by computed tomography.The correlation between radiography and pathology was high.Conclusions:The nomogram with radiological parameters can accurately predict OS for patients with pancreatic cancer after pancreatectomy plus venous reconstruction.