Correct diagnosis of vascular encasement and longitudinal extension of hilar cholangiocarcinoma by four-channel multidetector-row computed tomography

Clinical features and prediction of long-term survival after surgery for perihilar cholangiocarcinoma

INTRODUCTION

The treatment of perihilar Cholangiocarcinoma (pCCA) poses specific challenges not only due to its high perioperative complication rates but also due its dismal long-term prognosis with only a few long-term survivors (LTS) among the patients. Therefore, in this analysis characteristics and predictors of LTS in pCCA patients are investigated.

MATERIAL AND METHODS

In this single center analysis, patients undergoing curative-intent liver resection for pCCA between 2010 and 2022 were categorized into long-term and short-term survivors (STS) excluding perioperative mortality. Binary logistic regression was used to determine key differences between the groups and to develop a prognostic composite variable. This composite variable was subsequently tested in the whole cohort of surgically treated pCCA patients using Cox Regression analysis for cancer-specific survival (CSS).

RESULTS

Within a cohort of 209 individuals, 27 patients were identified as LTS (median CSS = 125 months) and 55 patients as STS (median CSS = 16 months). Multivariable analysis identified preoperative portal vein infiltration (OR = 5.85, p = 0.018) and intraoperative packed red blood cell (PRBC) transfusions (OR = 10.29, p = 0.002) as key differences between the groups. A prognostic composite variable based on these two features was created and transferred into a Cox regression model of the whole cohort. Here, the composite variable (HR = 0.35, p<0.001), lymph node metastases (HR = 2.15, p = 0.001) and postoperative complications (HR = 3.06, p<0.001) were identified as independent predictors of CSS.

CONCLUSION

Long-term survival after surgery for pCCA is possible and is strongly negatively associated with preoperative portal vein infiltration and intraoperative PRBC transfusion. As these variables are part of preoperative staging or can be modulated by intraoperative technique, the proposed prognostic composite variable can easily be transferred into clinical management to predict the oncological outcome of patients undergoing surgery for pCCA.

Feasibility of magnetic resonance imaging-based radiomics features for preoperative prediction of extrahepatic cholangiocarcinoma stage

AIM

The aim of this study is to develop and test radiomics models based on magnetic resonance imaging (MRI) to preoperatively and respectively predict the T stage, perineural invasion, and microvascular invasion of extrahepatic cholangiocarcinoma (eCCA) through a non-invasive approach.

METHODS

This research included 101 eCCA patients (29-83 years; 45 females and 56 males) between August 2011 and December 2019. Radiomics features were retrospectively extracted from T1-weighted imaging, T2-weighted imaging, diffusion-weighted imaging, and apparent diffusion coefficient map using MaZda software. The region of interest was manually delineated in the largest section on four MRI images as ground truth while keeping 1-2 mm margin to tumor border, respectively. Pretreatment, dimension reduction method, and classifiers were used to establish radiomics signatures for assessing three pathological characteristics of eCCA. Finally, independent training and testing datasets were used to assess radiomics signature performance based on receiver operating characteristic curve analysis, accuracy, precision, sensitivity, and specificity.

RESULTS

This study extracted 1208 radiomics features from four MRI images of each patient. The best performing radiomics signatures for assessing the T stage, perineural invasion, and microvascular invasion were respectively produced by L1_normalization + linear discriminant analysis (LDA) + logistic regression, Box_Cox transformer + LDA + K-nearest neighbor, and L2_normalization + LDA + AdaBoost. The area under the curve values of the radiomics signatures for predicting the training and testing cohorts in each subgroup were respectively 1 and 0.962 (T stage), 1 and 1 (both perineural invasion and microvascular invasion).

CONCLUSION

These proposed radiomic models based on MR images had powerful performance and high potential in predicting T stage, perineural, and microvascular invasion of eCCA.

REPORTING GUIDELINES/RESEARCH DESIGN

Prognostic study.

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.

Current Status and Recent Update of Imaging Evaluation for Peri-Hilar Cholangiocarcinoma

간문주변부의 해부학적 복잡성으로 인해 간문주변부 담관암은 그 진단과 치료가 어려운 질환으로 알려져 있다. 간문주변부 담관암이 의심되는 환자에 있어서, 영상 검사는 이상 소견의 발견 및 감별 진단, 종양의 종축 침범 부위의 파악, 인접 혈관 침범과 원격 전이 유무의 파악, 그리고 최종적으로 수술적 절제 가능 유무의 평가에 있어 핵심적인 역할을 하고 있다. 이 종설에서는 간문주변부 담관암의 분류 및 종양의 평가를 위해 권고되는 표준 영상 검사의 기법과 간문주변부 담관암의 전형적인 영상 소견에 대해 기술할 예정이다. 종축 방향의 종양 침범 파악, 인접 혈관 침범 및 원격 전이 유무의 평가에 있어서 각 영상 검사 소견과 그 진단능에 대해 논의할 예정이다. 이후 전통적인 절제 가능성 평가의 개념에 대해 고찰하고, 최근의 경향을 소개한다.

Radiologic Evaluation and Structured Reporting Form for Extrahepatic Bile Duct Cancer: 2019 Consensus Recommendations from the Korean Society of Abdominal Radiology

Radiologic imaging is important for evaluating extrahepatic bile duct (EHD) cancers; it is used for staging tumors and evaluating the suitability of surgical resection, as surgery may be contraindicated in some cases regardless of tumor stage. However, the published general recommendations for EHD cancer and recommendations guided by the perspectives of radiologists are limited. The Korean Society of Abdominal Radiology (KSAR) study group for EHD cancer developed key questions and corresponding recommendations for the radiologic evaluation of EHD cancer and organized them into 4 sections: nomenclature and definition, imaging technique, cancer evaluation, and tumor response. A structured reporting form was also developed to allow the progressive accumulation of standardized data, which will facilitate multicenter studies and contribute more evidence for the development of recommendations.

The prognostic value of portal vein and hepatic artery involvement in patients with perihilar cholangiocarcinoma

BACKGROUND

Although several classifications of perihilar cholangiocarcinoma (PHC) include vascular involvement, its prognostic value has not been investigated. Our aim was to assess the prognostic value of unilateral and main/bilateral involvement of the portal vein (PV) and hepatic artery (HA) on imaging in patients with PHC.

METHODS

All patients with PHC between 2002 and 2014 were included regardless of stage or management. Vascular involvement was defined as apparent tumor contact of at least 180° to the PV or HA on imaging. Kaplan-Meier method with log-rank test was used to compare overall survival (OS) between groups. Cox regression was used for multivariable analysis.

RESULTS

In total, 674 patients were included with a median OS of 12.2 (95% CI 10.6-13.7) months. Patients with unilateral PV involvement had a median OS of 13.3 (11.0-15.7) months, compared with 14.7 (11.7-17.6) in patients without PV involvement (p = 0.12). Patients with main/bilateral PV involvement had an inferior median OS of 8.0 (5.4-10.7, p < 0.001) months. Median OS for patients with unilateral HA involvement was 10.6 (9.3-12.0) months compared with 16.9 (13.2-20.5) in patients without HA involvement (p < 0.001). Patients with main/bilateral HA involvement had an inferior median OS of 6.9 (3.3-10.5, p < 0.001). Independent poor prognostic factors included unilateral and main/bilateral HA involvement, but not PV involvement.

CONCLUSION

Both unilateral and main HA involvement are independent poor prognostic factors for OS in patients presenting with PHC, whereas PV involvement is not.

Conditional survival in patients with unresectable perihilar cholangiocarcinoma

BACKGROUND

Conditional survival is the life expectancy from a point in time for a patient who has survived a specific period after presentation. The aim of the study was to estimate conditional survival for patients with unresectable perihilar cholangiocarcinoma.

METHODS

Patients with unresectable perihilar cholangiocarcinoma from two academic hospitals in the Netherlands between 2002 and 2012 were assessed. A multivariable Cox proportional hazards analysis was performed to identify risk factors associated with overall survival. Survival was estimated using the Kaplan-Meier method to evaluate factors associated with overall survival.

RESULTS

In total, 572 patients were included. Overall survival was 42% at one year and 6% at three years. The conditional chance of surviving three years was 15% at 1 year and increased to 38% at 2 years. Independent poor prognostic factors for overall survival were age ≥65 years, tumor size >3 cm on imaging, bilirubin levels (>250 μmol/L), CA19-9 level at presentation (>1000 U/ml), and suspected distant metastases on imaging. The conditional survival of patients with and without these prognostic factors was comparable after patients survived the first two or more years.

CONCLUSION

The conditional chance of surviving for patients with unresectable perihilar cholangiocarcinoma increases with time. Poor prognostic factors become less relevant once patients have survived two years.

Surveillance in cholangiocellular carcinoma

Cholangiocellular carcinoma is the most frequent malignant neoplasm originating from the epithelium of intra- or extrahepatic bile ducts. In the past decades, the incidence of cholangiocarcinoma has been shown to increase while overall mortality has remained high with an approximate 5-year overall survival below 20%. Surgery remains the only curative option while systemic treatment is limited to palliative chemotherapy. Therefore, surveillance strategies for patients at risk of developing cholangiocarcinoma are urgently needed, particularly in patients with primary sclerosing cholangitis and patients infected with liver flukes. Here we summarize the currently available data on surveillance of risk populations and methods for the detection of cholangiocarcinoma.

Surgical Therapy of Cholangiocarcinoma

BACKGROUND

The majority of patients with cholangiocarcinoma present with advanced disease that is often challenging to diagnose and to treat. The optimal preoperative evaluation requires a coordinated multidisciplinary approach. Surgical resection is the mainstay of therapy.

METHODS

This systematic review delineates surgical treatment strategies for cholangiocarcinoma in general as well as special considerations concerning the particular tumor localization. A literature search (see keywords) was conducted using PubMed and publications between 1990 and 2016 regarding resectable and advanced cholangiocarcinoma were reviewed. Selected studies were utilized based on their significance and innovation.

RESULTS

The type and extent of resection performed depends on the location of the cholangiocarcinoma within the liver or biliary tree and the extent of local tumor invasion. The common surgical strategy contains: (i) for intrahepatic tumors: tailored partial hepatectomy combined with extended hilar, suprapancreatic, celiac axis lymphadenectomy, (ii) for hilar tumors: complete resection of the extrahepatic biliary tree combined with extended hepatectomy inclusive of segment I, resection of portal vein bifurcation, and systematic N1/N2 lymphadenectomy, and (iii) for distal tumors: en bloc pancreatoduodenectomy combined with complete resection of the extrahepatic bile duct below the hepatic confluence and systematic N1/N2 lymphadenectomy. Pathologic confirmation is not required prior to resection. Preoperative biliary drainage and remnant liver volume augmentation are necessary in selected patients with intrahepatic or hilar cholangiocarcinoma considered for extensive liver resection.

CONCLUSION

Cure for cholangiocarcinoma requires complete surgical resection with histologically negative margins. R0 resection provides a satisfactory long-term outcome in patients with lymph node-negative stage. Neoadjuvant treatment followed by liver transplantation provides long-term survival in highly selected cases with localized, unresectable, lymph node-negative hilar cholangiocarcinoma.

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

BACKGROUND

In 2011, a new European Staging System (ESS) for perihilar cholangiocarcinoma (PHC) was proposed with the expressed purpose of comparing treatment and outcomes data between institutions. The goal of this study was to evaluate the feasibility of ESS data capture.

STUDY DESIGN

Forty-seven consecutive patients who underwent surgical resection for PHC between 1999 and 2013 were studied. Demographic variables, components of various staging systems (including the ESS), preoperative and perioperative details, pathology, and outcomes were recorded.

RESULTS

The mean patient age was 63.2 and 62% were male. Preoperative imaging included high-resolution CT in all patients, MRI in 34%, and PET in 11%. R0 resection was accomplished in 80% of patients. Four patients (8.5%) and 18 patients (38.3%), respectively, received neoadjuvant or adjuvant therapy. During a mean follow-up of 36 months, recurrence rate was 51.3% and 2- and 5-year survival rates were 69.4 and 33.3%, respectively. Analysis of data capture found that tumor (T) classification was indeterminable in 7/47 patients (14.9%). For two patients, the form (F) designation had insufficient data. The extent of vascular involvement (PV/HA) was different compared to preoperative imaging in nine patients (19.1%). The liver remnant volume (V) was calculated in only 18 patients (38.3%). The liver disease (D) variable did not account for four patients with inflammation/cirrhosis. In total, only 15 patients (31.9%) had all required elements to complete the ESS.

CONCLUSIONS

Without templated radiology, surgery, and pathology reports, the ESS cannot be applied to current clinical/research practice. Although resection continues to provide significant survival benefit to patients with perihilar cholangiocarcinoma, lack of an accurate prognostic tool for resectability and outcomes continues to be a major impediment to progress in the field.

[Preoperative imaging/operation planning for liver surgery]

The currently established standard for planning liver surgery is multistage contrast media-enhanced multidetector computed tomography (CM-CT), which as a rule enables an appropriate resection planning, e.g. a precise identification and localization of primary and secondary liver tumors as well as the anatomical relation to extrahepatic and/or intrahepatic vascular and biliary structures. Furthermore, CM-CT enables the measurement of tumor volume, total liver volume and residual liver volume after resection. Under the condition of normal liver function a residual liver volume of 25 % is nowadays considered sufficient and safe. Recent studies in patients with liver metastases of colorectal cancer showed a clear staging advantage of contrast media-enhanced magnetic resonance imaging (CM-MRI) versus CM-CT. In addition, most recent data showed that the use of liver-specific MRI contrast media further increases the sensitivity and specificity of detection of liver metastases. This imaging technology seems to lead closer to the ideal "one stop shopping" diagnostic tool in preoperative planning of liver resection.

Perihilar cholangiocarcinoma: a surgeon's viewpoint on current topics

Perihilar cholangiocarcinomas are defined anatomically as "tumors that are located in the extrahepatic biliary tree proximal to the origin of the cystic duct". However, as the boundary between the extrahepatic and intrahepatic bile ducts is not well defined, perihilar cholangiocarcinomas potentially include two types of tumors: one is the "extrahepatic" type, which arises from the large hilar bile duct, and the other is the "intrahepatic" type, which has an intrahepatic component with the invasion of the hepatic hilus. The new TNM staging system published by the International Union Against Cancer (UICC) has been well revised with regard to perihilar cholangiocarcinoma, but it still lacks stratification of patient prognosis and has little applicability for assessing the feasibility of surgical treatment; therefore, further refinement is essential. Most patients with perihilar cholangiocarcinomas present with jaundice, and preoperative biliary drainage is mandatory. Previously, percutaneous transhepatic biliary drainage was used in many centers; however, it is accepted that endoscopic naso-biliary drainage is the most suitable method of preoperative drainage. Portal vein embolization is now widely used as a presurgical treatment for patients undergoing an extended hepatectomy to minimize postoperative liver dysfunction. The surgical resection of a perihilar cholangiocarcinoma is technically demanding and continues to be the most difficult challenge for hepatobiliary surgeons. Because of advances in diagnostic and surgical techniques, surgical outcomes and survival rates after resection have steadily improved. However, survival, especially for patients with lymph node metastasis, is still unsatisfactory, and the establishment of adjuvant chemotherapy is necessary. Further synergy of endoscopists, radiologists, oncologists, and surgeons is required to conquer this intractable disease.

Novel multimodality treatment sequencing for extrahepatic (mid and distal) cholangiocarcinoma

Neoadjuvant chemoradiation has demonstrated significant advantages in the management of pancreatic adenocarcinoma. A similar tumor in a nearby anatomical location is extrahepatic cholangiocarcinoma, which has proven to be largely unresponsive to current forms of therapy. Neoadjuvant therapy for hilar cholangiocarcinoma has been combined with surgical resection and/or liver transplantation with a 25-33 % complete pathological response rate. We propose a wider application of neoadjuvant chemoradiation for patients with distal cholangiocarcinoma and present our rationale for this form of treatment sequencing.

Current management of cholangiocarcinoma

Cholangiocarcinoma is the second most common primary hepatobiliary malignancy after hepatocellular carcinoma and remains among the most difficult management problems faced by surgeons. Curative surgery is achieved in only 25% to 30% of patients. Local tumor extent, such as portal vein invasion and hepatic lobar atrophy, does not preclude resection. Long-term survival has been seen only in patients who underwent extensive liver resections, suggesting that bile-duct excision alone is less effective. The majority of patients have unresectable disease, with 20% to 30% incidence of distant metastasis at presentation. Unresectable patients should be referred for nonsurgical biliary decompression, and in potential curative resection candidates the use of biliary stents should be reduced. Liver transplantation provides the option of wide resection margins, expanding the indication of surgical intervention for selected patients who otherwise are not surgical candidates due to lack of functional hepatic reserve.

[Klatskin tumors: rational diagnostics and staging]

Klatskin tumors continue to be a challenge for diagnostic assessment and staging due to their longitudinal tumor growth along the perihilar bile ducts. Therefore the rate of non-resectable tumors remains relatively stable despite modern imaging and endoscopic techniques. This article reviews the current diagnostic methods for preoperative staging and the significance for predicting resectability.

Endoscopic diagnosis of extrahepatic bile duct carcinoma: Advances and current limitations

The accurate diagnosis of extrahepatic bile duct carcinoma is difficult, even now. When ultrasonography (US) shows dilatation of the bile duct, magnetic resonance cholangiopancreatography followed by endoscopic US (EUS) is the next step. When US or EUS shows localized bile duct wall thickening, endoscopic retrograde cholangiopancreatography should be conducted with intraductal US (IDUS) and forceps biopsy. Fluorescence in situ hybridization increases the sensitivity of brush cytology with similar specificity. In patients with papillary type bile duct carcinoma, three biopsies are sufficient. In patients with nodular or infiltrating-type bile duct carcinoma, multiple biopsies are warranted, and IDUS can compensate for the limitations of biopsies. In preoperative staging, the combination of dynamic multi-detector low computed tomography (MDCT) and IDUS is useful for evaluating vascular invasion and cancer depth infiltration. However, assessment of lymph nodes metastases is difficult. In resectable cases, assessment of longitudinal cancer spread is important. The combination of IDUS and MDCT is useful for revealing submucosal cancer extension, which is common in hilar cholangiocarcinoma. To estimate the mucosal extension, which is common in extrahepatic bile duct carcinoma, the combination of IDUS and cholangioscopy is required. The utility of current peroral cholangioscopy is limited by the maneuverability of the “baby scope”. A new baby scope (10 Fr), called “SpyGlass” has potential, if the image quality can be improved. Since extrahepatic bile duct carcinoma is common in the Far East, many researchers in Japan and Korea contributed these studies, especially, in the evaluation of longitudinal cancer extension.

New staging system and a registry for perihilar cholangiocarcinoma

Perihilar cholangiocarcinoma is one of the most challenging diseases with poor overall survival. The major problem for anyone trying to convincingly compare studies among centers or over time is the lack of a reliable staging system. The most commonly used system is the Bismuth-Corlette classification of bile duct involvement, which, however, does not include crucial information such as vascular encasement and distant metastases. Other systems are rarely used because they do not provide several key pieces of information guiding therapy. Therefore, we have designed a new system reporting the size of the tumor, the extent of the disease in the biliary system, the involvement of the hepatic artery and portal vein, the involvement of lymph nodes, distant metastases, and the volume of the putative remnant liver after resection. The aim of this system is the standardization of the reporting of perihilar cholangiocarcinoma so that relevant information regarding resectability, indications for liver transplantation, and prognosis can be provided. With this tool, we have created a new registry enabling every center to prospectively enter data on their patients with hilar cholangiocarcinoma (www.cholangioca.org). The availability of such standardized and multicenter data will enable us to identify the critical criteria guiding therapy.

Advances in diagnosis, treatment and palliation of cholangiocarcinoma: 1990-2009

Several advances in diagnosis, treatment and palliation of cholangiocarcinoma (CC) have occurred in the last decades. A multidisciplinary approach to this disease is therefore recommended. CC is a relatively rare tumor and the main risk factors are: chronic inflammation, genetic predisposition and congenital abnormalities of the biliary tree. While the incidence of intra-hepatic CC is increasing, the incidence of extra-hepatic CC is trending down. The only curative treatment for CC is surgical resection with negative margins. Liver transplantation has been proposed only for selected patients with hilar CC that cannot be resected who have no metastatic disease after a period of neoadjuvant chemo-radiation therapy. Magnetic resonance imaging/magnetic resonance cholangiopancreatography, positron emission tomography scan, endoscopic ultrasound and computed tomography scans are the most frequently used modalities for diagnosis and tumor staging. Adjuvant therapy, palliative chemotherapy and radiotherapy have been relatively ineffective for inoperable CC. For most of these patients biliary stenting provides effective palliation. Photodynamic therapy is an emerging palliative treatment that seems to provide pain relief, improve biliary patency and increase survival. The clinical utility of other emerging therapies such as transarterial chemoembolization, hepatic arterial chemoinfusion and high intensity intraductal ultrasound needs further study.