The impact of portal vein resection on outcome of hilar cholangiocarcinoma

A logistic regression model to predict long-term survival for borderline resectable pancreatic cancer patients with upfront surgery

BACKGROUND

The machine learning model, which has been widely applied in prognosis assessment, can comprehensively evaluate patient status for accurate prognosis classification. There still has been a debate about which predictive strategy is better in patients with borderline resectable pancreatic cancer (BRPC). In the present study, we establish a logistic regression model, aiming to predict long-term survival and identify related prognostic factors in patients with BRPC who underwent upfront surgery.

METHODS

Medical records of patients with BRPC who underwent upfront surgery with portal vein resection and reconstruction from Jan. 2011 to Dec. 2020 were reviewed. Based on postoperative overall survival (OS), patients were divided into the short-term group (≤ 2 years) and the long-term group (> 2 years). Univariate and multivariate analyses were performed to compare perioperative variables and long-term prognoses between groups to identify related independent prognostic factors. All patients are randomly divided into the training set and the validation set at a 7:3 ratio. The logistic regression model was established and evaluated for accuracy through the above variables in the training set and the validation set, respectively, and was visualized by Nomograms. Meanwhile, the model was further verified and compared for accuracy, the area under the curve (AUC) of the receiver operating characteristic curves (ROC), and calibration analysis. Then, we plotted and sorted perioperative variables by SHAP value to identify the most important variables. The first 4 most important variables were compared with the above independent prognostic factors. Finally, other models including support vector machines (SVM), random forest, decision tree, and XGBoost were also constructed using the above 4 variables. 10-fold stratified cross-validation and the AUC of ROC were performed to compare accuracy between models.

RESULTS

104 patients were enrolled in the study, and the median OS was 15.5 months, the 0.5-, 1-, and 2- years OS were 81.7%, 57.7%, and 30.8%, respectively. In the long-term group (n = 32) and short-term group (n = 72), the overall median survival time and the 1-, 2-, 3- years overall survival were 38 months, 100%, 100%, 61.3% and 10 months, 38.9%, 0%, 0%, respectively. 4 variables, including age, vascular invasion length, vascular morphological malformation, and local lymphadenopathy were confirmed as independent risk factors between the two groups following univariate and multivariate analysis. The AUC between the training set (n = 72) and the validation set (n = 32) were 0.881 and 0.875. SHAP value showed that the above variables were the first 4 most important. The AUC following 10-fold stratified cross-validation in the logistic regression (0.864) is better than SVM (0.693), random forest (0.789), decision tree (0.790), and XGBoost (0.726).

CONCLUSION

Age, vascular invasion length, vascular morphological malformation, and local lymphadenopathy were independent risk factors for long-term survival of BRPC patients with upfront surgery. The logistic regression model plays a predictive role in long-term survival and may further assist surgeons in deciding the treatment option for BRPC patients.

Surgical management of hilar cholangiocarcinoma: Controversies and recommendations

Hilar cholangiocarcinomas are highly aggressive malignancies. They are usually at an advanced stage at initial presentation. Surgical resection with negative margins is the standard of management. It provides the only chance of cure. Liver transplantation has increased the number of 'curative' procedures for cases previously considered to be unresectable. Meticulous and thorough preoperative planning is required to prevent fatal post-operative complications. Extended resection procedures, including hepatic trisectionectomy for Bismuth type IV tumors, hepatopancreaticoduodenectomy for tumors with extensive longitudinal spread, and combined vascular resection with reconstruction for tumors involving hepatic vascular structures, are challenging procedures with surgical indications expanded. Liver transplantation after the standardization of a neoadjuvant protocol described by the Mayo Clinic has increased the number of patients who can undergo operation.

Vascular Involvements in Cholangiocarcinoma: Tips and Tricks

Cholangiocarcinoma (CCA) is an aggressive malignancy of the biliary tract. To date, surgical treatment remains the only hope for definitive cure of CCA patients. Involvement of major vascular structures was traditionally considered a contraindication for resection. Nowadays, selected cases of CCA with vascular involvement can be successfully approached. Intrahepatic CCA often involves the major hepatic veins or the inferior vena cava and might necessitate complete vascular exclusion, in situ hypothermic perfusion, ex situ surgery and reconstruction with autologous, heterologous or synthetic grafts. Hilar CCA more frequently involves the portal vein and hepatic artery. Resection and reconstruction of the portal vein is now considered a relatively safe and beneficial technique, and it is accepted as a standard option either with direct anastomosis or jump grafts. However, hepatic artery resection remains controversial; despite accumulating positive reports, the procedure remains technically challenging with increased rates of morbidity. When arterial reconstruction is not possible, arterio-portal shunting may offer salvage, while sometimes an efficient collateral system could bypass the need for arterial reconstructions. Keys to achieve success are represented by accurate selection of patients in high-volume referral centres, adequate technical skills and eclectic knowledge of the various possibilities for vascular reconstruction.