Evaluating the Clinical Applicability of the European Staging System for Perihilar Cholangiocarcinoma

Efficacy of Extended Modification in Left Hemihepatectomy for Advanced Perihilar Cholangiocarcinoma: Comparison Between H12345'8'-B-MHV and H1234-B

OBJECTIVE

The aim of this study was to verify the prognostic impact of the tumor exposure at the liver transection margin (LTM) in left-sided perihilar cholangiocarcinoma and the impact of middle hepatic vein (MHV) resection on this exposure.

BACKGROUND

In perihilar cholangiocarcinoma, tumors are unexpectedly exposed at the LTM during left hemihepatectomy (LH).

METHODS

Patients who underwent LH for perihilar cholangiocarcinoma during 2002 to 2018 were retrospectively evaluated. LH was classified into conventional and extended types, which preserved and resected the MHVs, respectively. Positive LTM was defined as the involvement of invasive carcinoma at the liver transection plane and/or the adjacent Glissonean pedicle exposed. The clinicopathologic features and survival outcomes were compared between procedures.

RESULTS

Among 236 patients, conventional and extended LHs were performed in 198 and 38 patients, respectively. The LTM was positive in 31 (13%) patients, with an incidence of 14% versus 8% ( P = 0.432) and 24% versus 0% in advanced tumors ( P = 0.011). Tumor size ≥ 18 mm ( P = 0.041), portal vein invasion ( P = 0.009), and conventional LH ( P = 0.028) independently predicted positive LTM. In patients with negative LTM, the survival was comparable between the two groups: 60.4% versus 59.2% at 3 years ( P = 0.206), which surpassed 17.7% for those with positive LTM in the conventional group ( P < 0.001). Multivariable analysis demonstrated that LTM status was an independent prognostic factor ( P = 0.009) along with ductal margin status ( P = 0.030).

CONCLUSIONS

The LTM status is an important prognostic factor in perihilar cholangiocarcinoma. Extended LH reduced the risk of tumor exposure at the LTM with a subsequent improvement in the survival, particularly in advanced tumors.

Superiority of clinical American Joint Committee on Cancer T classification for perihilar cholangiocarcinoma

BACKGROUND

Clinical tumor staging is essential information for making a therapeutic decision in cancer. This study aimed to identify the optimal tumor classification system for predicting resectability and survival probability in perihilar cholangiocarcinoma.

METHODS

Patients who were treated for perihilar cholangiocarcinoma between 2009 and 2018 were enrolled. Local tumor extension was staged radiologically according to a diameter-based classification system in addition to the AJCC, Blumgart, and Bismuth systems. Survival and resectability were compared between T subgroups, and the discriminability of the four systems was assessed with Harrell's concordance index (C-index).

RESULTS

Among 702 study patients, 559 (80.0%) underwent laparotomy, 489 (70.0%) of whom underwent resection. The resectability significantly decreased for more advanced tumors in all systems (P < .001); the AJCC system had the greatest discriminability for resectability (area under the curve 0.721). Overall survival at 5 years was 69.9% for AJCC cT1, 45.8% for cT2, 31.8% for cT3, and 15.3% for cT4 tumors (cT1 vs cT2; P = .002, cT2 vs cT3; P = .008 and cT3 vs cT4; P < .001). The AJCC system had the largest C-index of 0.627.

CONCLUSIONS

The AJCC T system was the optimal classification system for predicting resectability and survival in perihilar cholangiocarcinoma.

Modification and comparison of CT criteria in the preoperative assessment of hepatic arterial invasion by hilar cholangiocarcinoma

OBJECTIVE

To compare the diagnostic performance of three CT criteria and two signs in evaluating hepatic arterial invasion by hilar cholangiocarcinoma.

METHODS

In this study, we retrospectively reviewed the CT images of 85 patients with hilar cholangiocarcinoma. Modified Loyer's, Lu's, and Li's standards were used to evaluate hepatic arterial invasion by hilar cholangiocarcinoma with the reference of intraoperative findings and/or the postoperative pathological diagnosis. Arterial tortuosity and contact length were also evaluated.

RESULTS

Loyer's, Lu's, and Li's standards showed sensitivities of 91.7%, 90.3%, and 72.2%, specificities of 94.0%, 94.5%, and 95.6%, and accuracies of 93.3%, 93.3%, and 89.0%, respectively, in evaluating hepatic arterial invasion by hilar cholangiocarcinoma. Loyer's and Lu's standards and contact length performed better than Li's standard (P < 0.001). Arterial tortuosity performed worse than other criteria (P < 0.001). The CT criteria performed best in evaluating proper hepatic arterial invasion compared with the left and right hepatic artery. When the cut-off contact length of 6.73 mm was combined with Loyer's standard, 4 false-negative cases could be avoided.

CONCLUSIONS

Loyer's and Lu's standards and the contact length performed best in evaluating hepatic arterial invasion by hilar cholangiocarcinoma on preoperative CT images, particularly in assessing the proper hepatic artery. Arterial tortuosity could serve as an important supplement. The combination of the contact length and Loyer's standard could improve the diagnostic performance.

Survival analysis of patients with stage T2a and T2b perihilar cholangiocarcinoma treated with radical resection

BACKGROUND

Both the 7th and 8th editions of the American Joint Committee on Cancer (AJCC) staging system for perihilar cholangiocarcinoma (pCCA) had the same definition for T2a and T2b. But the value of this classification as prognostic factor remains unclear.

METHODS

178 patients with stage T2a or T2b who underwent curative intent resection for pCCA between Jan 2010 and Dec 2018 were enrolled. Relationships between survival and clinicopathological factors including patient demographics and tumor characteristics were evaluated using univariate and multivariate Cox regression analysis. The overall survival (OS) were calculated by Kaplan-Meier method.

RESULTS

There was no significant difference in OS between T2a and T2b groups, and the median OS duration were 37 and 31 months (P = 0.354). Both the 7th and 8th edition of the AJCC TNM staging demonstrated a poor prognostic predictive performance. High level of preoperative AST (≥85.0 IU/L) and CA19-9 (≥1000 U/mL), vascular resection and lower pathological differentiation of the tumor were the independent predictors for poor survival after resection.

CONCLUSION

The newly released 8th edition of AJCC staging system demonstrated a poor ability to discriminate the prognosis of patients with stage T2a and T2b pCCA after resection.

Predictive performance of Blumgart T staging for perihilar cholangiocarcinoma in a Japanese center

BACKGROUND

The Blumgart system has been used for local tumor assessment in perihilar cholangiocarcinoma to predict resectability and survival, and T3 tumors are considered unresectable disease. The aim was to validate the predictive performance of this system using a Japanese cohort.

METHODS

Medical records of consecutive patients with perihilar cholangiocarcinoma between 2006 and 2016 were retrospectively reviewed. Resectability, surgical procedure, R0 resection rate, and survival were compared among T stages.

RESULTS

Among 729 study patients, 191 patients had T1 tumors, 94 patients had T2 tumors, and 444 (60.9%) patients had T3 tumors according to the Blumgart T stage. Resection was performed in 513 (70.4%) patients; resectability rate decreased with the progression of T stage: 89.0% in T1, 79.8% in T2, and 60.4% in T3 tumors (P < 0.001). The incidences of left hepatic trisectionectomy and portal vein resection were 44.0% and 54.1%, respectively, in patients with T3 tumors, which were significantly greater than those of T1/2 tumors (P = 0.001 and P < 0.001). R0 resection reduced with advanced T stage: 92.4% in T1, 81.3% in T2, and 70.9% in T3 tumors (P < 0.001). The 5-year survival rate was 53.4%, 38.4%, and 19.7% in T1, T2, and T3 tumors, respectively (P < 0.001); that was 59.6%, 48.6%, and 30.7%, respectively, in the resected cohort (P < 0.001).

CONCLUSION

Blumgart T stage was closely associated with the resectability rate, surgical procedures, R0 resection rate, and survival time, suggesting that the T stage works as well as a presurgical staging system. However, the unresectable classification of T3 tumors should be revised.

Preoperative Risk Score to Predict Occult Metastatic or Locally Advanced Disease in Patients with Resectable Perihilar Cholangiocarcinoma on Imaging

BACKGROUND

Many patients with resectable perihilar cholangiocarcinoma (PHC) on imaging are diagnosed intraoperatively with occult metastatic or locally advanced disease, precluding a curative-intent resection. This study aimed to develop and validate a preoperative risk score.

STUDY DESIGN

Patients with resectable PHC on imaging who underwent operations in 2 high-volume centers (US and Europe) between 2000 and 2015 were included. Multivariable logistic regression analysis was used to develop the risk score. Cross-validation was used to validate the score, alternating the 2 centers as "training" and "testing" datasets.

RESULTS

Of 566 patients who underwent operations, 309 (55%) patients had a resection, and in 257 (45%) patients, a curative-intent resection was precluded due to distant metastasis (n = 151 [27%]) or locally advanced disease (n = 106 [19%]). Preoperative predictors included bilirubin >2 mg/dL, bile duct involvement on imaging, portal vein involvement on imaging (≥180 degrees), hepatic artery involvement on imaging (≥180 degrees), and suspicious lymph nodes on imaging. The new risk score (c-index 0.75 after cross-validation) provided significantly more accurate predictions than the Bismuth classification (c-index 0.62), Blumgart T-staging (c-index 0.67), and cTNM staging (c-index 0.68). The new risk score identified 4 risk groups for occult metastatic or locally advanced disease: low (14.7%), intermediate (29.5%), high (47.3%), and very high risk (81.3%). The preoperative score groups also predicted survival after operation, irrespective of intraoperative findings (p < 0.001).

CONCLUSIONS

The validated risk score can predict occult distant metastatic or locally advanced PHC based on 5 preoperatively available factors. The score can be useful in preoperative shared decision making and selection of patients in neoadjuvant clinical trials.

Preoperative prediction of curative surgery of perihilar cholangiocarcinoma by combination of endoscopic ultrasound and computed tomography

Background

Perihilar cholangiocarcinomas are often considered incurable. Late diagnosis is common. Advanced disease therefore frequently causes questioning of curative surgical outcome.

Aim

This study aimed to develop a prediction model of curative surgery in patients suffering from perihilar cholangiocarcinomas based on preoperative endosonography and computer tomography.

Methods

A cohort of 81 patients (median age 67 (54-75) years, 62% male) with perihilar cholangiocarcinoma was retrospectively analyzed. Multivariate logistic regression analysis of staging variables taken from the European Staging System was performed and applied to ROC analysis.

Results

The correlation of predicted rates of eligibility for surgery with actual rates reached AUC values between 0.652 and 0.758 for endosonography and computer tomography (p < 0.05 each). Best prediction for curative surgical option was achieved by combining endosonography and computer tomography (AUC: 0.787; 95% CI 0.680-0.893, p < 0.0001). A predictive model (pSurg) was developed using multivariate analysis.

Conclusions

Our predictive web-based model pSurg with inclusion of T, N, M, B, PV, HA and V stage of the recently published European Staging System for perihilar cholangiocarcinoma results in highly significant predictability for curative surgery when combining preoperative endosonography and computer tomography, thus allowing for better patient selection in terms of possibility of curative surgery.