Predictive score for identifying intrahepatic cholangiocarcinoma patients without lymph node metastasis: a basis for omitting lymph node dissection

BACKGROUND

This study aimed to develop a predictive score for intrahepatic cholangiocarcinoma (ICC) in patients without lymph node metastasis (LNM) using preoperative factors.

METHODS

A retrospective analysis of 113 ICC patients who underwent liver resection with systemic lymph node dissection between 2002 and 2021 was conducted. A multivariate logistic regression analysis was used as a predictive scoring system for node-negative patients based on the β coefficients of preoperatively available factors.

RESULTS

LNM was observed in 36 patients (31.9%). Four factors were associated with LNM: suspicion of LNM on MDCT (odds ratio [OR] 13.40, p < 0.001), low-vascularity tumor (OR 6.28, p = 0.005), CA19-9 ≥500 U/mL (OR 5.90, p = 0.010), and tumor location in the left lobe (OR 3.67, p = 0.057). The predictive scoring system was created using these factors (assigning 3 points for suspected LNM on MDCT, 2 points for CA19-9 ≥500 U/mL, 2 points for low vascularity tumor, and 1 point for tumor location in the left lobe). A score cutoff value of 4 resulted in 0.861 sensitivity and a negative predictive value of 0.922 for detecting LNM. Notably, no patients with peripheral tumors and a score of ≤3 had LNM.

CONCLUSION

The developed scoring system may effectively help identify ICC patients without LNM.

Surgical interpretation of the WHO subclassification of intrahepatic cholangiocarcinoma: a narrative review

Intrahepatic cholangiocarcinoma (iCCA) has been subclassified by its gross morphology into the mass-forming (MF), periductal-infiltrating (PI), and intraductal growth (IG) types and their combinations. This classification correlates well with clinical features; for example, MF-iCCA has less lymph-node metastasis and a better prognosis than PI-iCCA. According to the recently accumulated evidence from histological investigations, the WHO classification endorsed a subclassification scheme in which iCCA cases are classified into small- and large-duct types. Small-duct iCCA is considered to originate from septal or smaller bile ducts and is characterized by less frequent lymph-node metastasis, a favorable prognosis, and an MF appearance. Large-duct iCCA arises around the second branch of the biliary tree and has more aggressive biology and distinct genetic abnormalities. According to the practice guidelines for iCCA from the Liver Cancer Study Group of Japan and the National Comprehensive Cancer Network, upfront surgery is recommended for iCCA without distant metastasis regardless of the morphological subtype, based on clinical experience. In consideration of the biological heterogeneity of iCCA, the treatment strategy for iCCA needs to be reconsidered based on the WHO subtypes.

Lymph Node Dissection in Intrahepatic Cholangiocarcinoma: a Critical and Updated Review of the Literature

BACKGROUND

Lymphatic spread of intrahepatic cholangiocarcinoma (iCCA) is common and negatively impacts survival. However, the precise role of lymph node dissection (LND) in oncologic outcomes for patients with intrahepatic cholangiocarcinoma remains to be established.

METHODS

Updated evidence on the preoperative diagnosis and prognostic value of lymph node metastasis is reviewed, as well as the potential benefit of LND in patients with iCCA.

RESULTS

The ability to accurately determine nodal status for iCCA with current imaging modalities is equivocal. LND has prognostic value for both survival and disease recurrence. However, execution rates of LND are highly varied in the literature, ranging from 26.9 to 100%. At least 6 lymph nodes should be examined from nodal stations of the hepatoduodenal ligament and hepatic artery as well as based on the location of the primary tumor. Neoadjuvant therapies may be beneficial if lymph node metastases at diagnosis are suspected. Surgeons performing a minimally invasive approach should focus on increasing LND rates and harvesting ≥ 6 lymph nodes. Lymph node negativity is required in patients with iCCA being considered for liver transplantation under investigational protocols.

CONCLUSION

Despite an upward trend in the LND rate, the reality is that only 10% of patients with iCCA receive an adequate LND. This review underscores the importance of routinely increasing the rate of adequate LND in these patients in order to achieve accurate staging, appropriately select patients for adjuvant therapy, and improve the prognosis of clinical outcomes. While prospective data is lacking, the therapeutic impact of LND remains unknown.

Role of routine lymph node dissection alongside resection of intrahepatic cholangiocarcinoma: Systematic review and meta-analysis

BACKGROUND

The global incidence of intrahepatic cholangiocarcinoma (ICCA) is soaring. Due to often delayed presentation, only a narrow spectrum of the disease is usually surgically resectable. To more accurately stage the disease, reduce recurrence, and improve overall survival, surgical teams are increasingly performing intraoperative lymph node dissection (LND) as well. This procedure has its associated morbidity, while there is no consensus or formal guidelines on its role in this setting. Hence, there is a need to better delineate the evidence for performing LND alongside surgical resection of the ICCA.

AIM

To perform a systematic review and meta-analysis on the role of LND in improving prognostication and survival post-resection of ICCA.

METHODS

We performed a systematic literature search using Pubmed, Medline, Embase, and the Cochrane Library, for all studies involving LND, ICCA, and surgical resection using several keywords, Medical Subject Headings (MeSH) tags, and appropriate synonyms. All clinical studies comparing curative intent resection of ICCA with LND vs resection without LND were included, while single-arm case series, studies with insufficient data, and duplicates were excluded. We included all English-language studies from the different academic databases up till early December 2022. The primary outcome measures were set for overall survival (OS) and disease-free survival (DFS).

RESULTS

This systematic review and meta-analysis included 15 studies that fulfilled the selection criteria comprising 11413 patients with surgically-resectable ICCA, of whom 6424 (56.3%) underwent hepatectomy with LND while the remainder underwent hepatectomy only. In patients who underwent LND, on average, 27.7% of the resected lymph nodes were positive for metastatic disease. Overall, the results showed that performing LND did not significantly improve OS or DFS. However, the effect of LND on OS showed a degree of variability by geographical region, in Eastern and Western countries. As LND is increasingly being performed, further time-based analysis was undertaken to identify time-dependent changes in the role of LND. An increasing adoption of LND was not associated with improved OS. Furthermore, no roles were identified for neoadjuvant/adjuvant chemotherapy or increasing lymph node retrieval in improving OS either.

CONCLUSION

LND might aid in staging, prognosticating, and deciding further management of resected ICCA, but does not improve OS and DFS and is unsuitable for high-risk patients unlikely to benefit from further treatments.

Preoperative prediction model for microvascular invasion in HBV-related intrahepatic cholangiocarcinoma

BACKGROUND AND AIMS

Preoperative prediction of microvascular invasion (MVI) using a noninvasive method remain unresolved, especially in HBV-related in intrahepatic cholangiocarcinoma (ICC). This study aimed to build and validate a preoperative prediction model for MVI in HBV-related ICC.

METHODS

Patients with HBV-associated ICC undergoing curative surgical resection were identified. Univariate and multivariate logistic regression analyses were performed to determine the independent risk factors of MVI in the training cohort. Then, a prediction model was built by enrolling the independent risk factors. The predictive performance was validated by receiver operator characteristic curve (ROC) and calibration in the validation cohort.

RESULTS

Consecutive 626 patients were identified and randomly divided into the training (418, 67%) and validation (208, 33%) cohorts. Multivariate analysis showed that TBIL, CA19-9, tumor size, tumor number, and preoperative image lymph node metastasis were independently associated with MVI. Then, a model was built by enrolling former fiver risk factors. In the validation cohort, the performance of this model showed good calibration. The area under the curve was 0.874 (95% CI: 0.765-0.894) and 0.729 (95%CI: 0.706-0.751) in the training and validation cohort, respectively. Decision curve analysis showed an obvious net benefit from the model.

CONCLUSION

Based on clinical data, an easy model was built for the preoperative prediction of MVI, which can assist clinicians in surgical decision-making and adjuvant therapy.

EASL-ILCA Clinical Practice Guidelines on the management of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) develops inside the liver, between bile ductules and the second-order bile ducts. It is the second most frequent primary liver cancer after hepatocellular carcinoma, and its global incidence is increasing. It is associated with an alarming mortality rate owing to its silent presentation (often leading to late diagnosis), highly aggressive nature and resistance to treatment. Early diagnosis, molecular characterisation, accurate staging and personalised multidisciplinary treatments represent current challenges for researchers and physicians. Unfortunately, these challenges are beset by the high heterogeneity of iCCA at the clinical, genomic, epigenetic and molecular levels, very often precluding successful management. Nonetheless, in the last few years, progress has been made in molecular characterisation, surgical management, and targeted therapy. Recent advances together with the awareness that iCCA represents a distinct entity amongst the CCA family, led the ILCA and EASL governing boards to commission international experts to draft dedicated evidence-based guidelines for physicians involved in the diagnostic, prognostic, and therapeutic management of iCCA.

Application of Hazard Function to Investigate Recurrence of Intrahepatic Cholangiocarcinoma After Curative-Intent Liver Resection: A Novel Approach to Characterize Recurrence

PURPOSE

To investigate recurrence patterns after surgery for intrahepatic cholangiocarcinoma (ICC) relative to lymph node status, tumor extension, tumor burden score (TBS), and adjuvant chemotherapy.

METHODS

Patients who underwent curative-intent resection for ICC from 1990 to 2020 were enrolled from a multi-institutional database. The hazard function was applied to plot the hazard rates over time, with further stratification by T and N AJCC 8th edition categories, TBS, and adjuvant chemotherapy.

RESULTS

A total of 1192 patients underwent curative-intent resection for ICC and 59.9% experienced recurrence. Overall, the peak of recurrence occurred at 6.6 months. Among patients with negative lymph nodes, the T4-category had a higher peak rate of recurrence (0.1199 at 10.2 months) compared with other T-categories, while high TBS had an earlier peak of recurrence (4.2 months) compared with lower TBS. Among patients with N1 disease, T2-T4 categories had multipeak patterns of recurrence with higher hazard rates during the first 3 years after surgery in comparison with T1-category, while patients with high TBS had an earlier (4.0 months) and higher hazard peak rate compared with lower TBS groups. The administration of adjuvant chemotherapy was associated with delayed hazard rates of recurrence for N1 (4 months) and NX (6 months) categories.

DISCUSSION

The novel application of the hazard function to assess hazard rates and timing patterns of recurrence following resection for ICC demonstrated that recurrence varied based on T- and N-categories, as well as TBS. Hazard function-based recurrence data may be helpful to tailor counseling, surveillance, and adjuvant therapy recommendations.

Lymph Node Examination and Patterns of Nodal Metastasis Among Patients with Left- Versus Right-Sided Intrahepatic Cholangiocarcinoma After Major Curative-Intent Resection

BACKGROUND

We sought to investigate whether the unique lateral patterns of lymphatic drainage impacted lymphadenectomy (LND), lymph node metastasis (LNM), and long-term survival of patients after curative hemi-hepatectomy for left- versus right-sided intrahepatic cholangiocarcinoma (ICC).

METHODS

Data on patients who underwent curative hemi-hepatectomy for left- or right-sided ICC were collected from 15 high-volume centers worldwide, as well as from the Surveillance, Epidemiology, and End Results (SEER) registry. Primary outcomes included overall survival (OS) and disease-free survival (DFS).

RESULTS

Among 697 patients identified from the multi-institutional database, patients who underwent hemi-hepatectomy for left-sided ICC (n = 363, 52.1%) were more likely to have an increased number of LND versus patients with right-sided ICC (n = 334, 47.9%) (median, left 5 versus right 3, p = 0.012), although the frequency (left 66.4% versus right 63.8%, p = 0.469) and station (beyond station no. 12, left 25.3% versus right 21.1%, p = 0.293) were similar. Consequently, left-sided ICC was associated with higher incidence of LNM (left 33.3% versus right 25.7%, p = 0.036), whereas the station and number of LNM were not different (both p > 0.1). There was no difference in OS (median, left 34.9 versus right 29.6 months, p = 0.130) or DFS (median, left 14.5 versus right 15.2 months, p = 0.771) among patients who underwent hemi-hepatectomy for left- versus right-sided ICC, which were also verified in the SEER dataset. LNM beyond station no. 12 was associated with even worse long-term survival versus LNM within station no. 12 among patients with either left- or right-sided ICC after curative-intent resection (all p < 0.05).

CONCLUSIONS

The unique lateral patterns of lymphatic drainage were closely related to utilization of LND, as well as LNM of left- versus right-sided ICC.

Micro-lymph node metastasis in intrahepatic cholangiocarcinoma showing pathological complete response to primary tumor and intrahepatic metastasis treated by gemcitabine plus cisplatin chemotherapy and radical surgery

Surgical resection is the only curative treatment option for achieving long-term survival in biliary tract cancer patients. However, regional lymph node dissection in intrahepatic cholangiocarcinoma (ICC) is controversial. Herein, we document our experience with a 76-year-old man who had a 70 mm mass in liver segments 6 and 7 and a 10 mm mass in liver segment 3, which were diagnosed as poorly differentiated adenocarcinomas by needle biopsy. Lymphadenopathy was not evident on multidetector computed tomography scanning. Twenty courses of gemcitabine plus cisplatin chemotherapy were administered to the patient. The tumor masses shrunk and exhibited a partial response to chemotherapy as per the Response Evaluation Criteria in Solid Tumors version 1.1. Although tumor markers were all within normal limits, renal function parameters showed deterioration due to systemic chemotherapy. Therefore, continuing systemic chemotherapy was deemed unfeasible and we decided to perform a radical resection using extended posterior segmentectomy and partial liver resection with regional lymph node dissection. Postoperative histopathological examination revealed complete response of primary tumor and intrahepatic metastases; however, a micro-lymph node metastasis was found. The patient is still alive, without recurrence, more than 30 months after treatment initiation and 15 months after surgery. Even if remarkably effective pathological findings may be observed in the primary tumor, there are cases in which a micro-lymph node metastasis remains that are not identified on imaging examinations. Thus, regional lymphadenectomy may be useful in obtaining the exact state of disease progression and evaluation of chemotherapeutic effect in radical surgery.

Modification of the AJCC/UICC 8th edition staging system for intrahepatic cholangiocarcinoma: proposal for an alternative staging system from cholangiocarcinoma-prevalent Northeast Thailand

BACKGROUND

Intrahepatic cholangiocarcinoma (iCCA) arises from bile ducts within the liver. Thailand has the highest incidence of CCA worldwide, with a high mortality rate. Early diagnosis and accurate prognostic stratification can improve overall survival. We aim to modify the AJCC/UICC 8th edition staging system for iCCA by creating the Khon Kaen University (KKU) staging system for more precise patient stratification and prognostic prediction.

METHODS

A total of 298 iCCA patients who underwent hepatectomy were included in this retrospective study at the Srinagarind Hospital, Khon Kaen University, Thailand. Univariate and multivariate analysis were performed to examine survival rate, hazard ratio, and prognostic factors.

RESULTS

Univariate and multivariate analysis of the cohort showed that growth patterns, histological type, histological grade, lymph node metastasis and distant metastasis were independent prognostic factors when compared to the respective reference groups. The 8th AJCC staging system incorporated growth patterns into the KKU staging system. This model modified AJCC stages I, II, and III for better prediction of patient survival.

CONCLUSION

Growth patterns were incorporated to improve the 8th AJCC staging system for prognostication of iCCA patients in Northeast Thailand. We propose the KKU staging system as an alternative model for iCCA staging to augment the accuracy of survival prognostication.

Radiomics-Based Preoperative Prediction of Lymph Node Metastasis in Intrahepatic Cholangiocarcinoma Using Contrast-Enhanced Computed Tomography

BACKGROUND

Lymph node (LN) metastasis is significantly associated with worse prognosis for patients with intrahepatic cholangiocarcinoma (ICC). Improvement in preoperative assessment on LN metastasis helps in treatment decision-making. We aimed to investigate the role of radiomics-based method in predicting LN metastasis for patients with ICC.

METHODS

A total of 296 patients with ICC who underwent curative-intent hepatectomy and lymphadenectomy at two centers in China were analyzed. Radiomic features, including histogram- and wavelet-based features, shape and size features, and texture features were extracted from four-phase computerized tomography (CT) images. The clinical and conventional radiological variables which were independently associated with LN metastasis were also identified. A combined nomogram predicting LN metastasis was developed, and its performance was determined by discrimination, calibration, and stratification of long-term prognosis. The results were validated by the internal and external validation cohorts.

RESULTS

Twenty-four radiomic features were selected into the nomogram. The established nomogram demonstrated good discrimination and calibration, with areas under the curve (AUCs) of 0.98 [95% confidence interval (CI) 0.96-0.99], 0.93 (0.88-0.98), and 0.89 (0.81-0.96) in the training and two validation cohorts, respectively. The 5-year overall survival (OS) and recurrence-free survival (RFS) rates of patients with high risk of LN metastasis as grouped by nomogram were poorer than those of patients with low risk in the training cohort (OS 28.8% versus 53.9%, p < 0.001; RFS 26.3% versus 44.2%, p = 0.001). Similar results were observed in the two validation cohorts.

CONCLUSIONS

Radiomics-based method provided accurate prediction of LN metastasis and prognostic assessment for ICC patients, and might aid the preoperative surgical decision.

[Cholangiocarcinoma-Intrahepatic to hilar bile duct cancer]

BACKGROUND

In addition to conditioning measures in liver surgery, perioperative anti-tumor therapy is becoming increasingly more important in cholangiocarcinoma (CCA).

OBJECTIVE

Systematic literature review on the status of multimodal and in particular neoadjuvant therapy for CCA.

MATERIAL AND METHODS

Literature overview of the current scientific original and review articles.

RESULTS

Resection and rarely also liver transplantation are still the only curative treatment approaches for CCA in the non-distant metastatic stage; however, long-term results, e.g. in node positive tumors, are still unsatisfactory. Adjuvant chemotherapy is now standard but cannot be used in many patients. Neoadjuvant concepts include chemotherapy and local and locoregional procedures, such as radioembolization. Both are increasingly used in intrahepatic CCA (iCCA) but rarely in perihilar CCA. Initial data show that this is very effective in iCCA to achieve secondary operability in primarily inoperable cases. In addition, based on the current literature, neoadjuvant therapy also seems justified in operable intrahepatic CCA with a high risk of recurrence (e.g. lymph node metastases).

CONCLUSION

There is a high potential for the use of multimodal therapy in CCA, which could further increase in the near future as a result of new therapeutic agents. Due to the lack of evidence clear recommendations cannot be given; however, it is becoming apparent that neoadjuvant therapy is gaining importance in iCCA and is already increasingly used as part of individual concepts in patients with a high risk of recurrence.

Treatment of Intrahepatic Cholangiocarcinoma-A Multidisciplinary Approach

Simple Summary

This review discusses multimodality treatment strategies for intrahepatic cholangiocarcinoma (iCC). Surgical resection remains the only potentially curative therapeutic option and the central cornerstone of treatment. Adjuvant systemic treatment will be recommended after resection or in the palliative setting. Increasing knowledge of phenotypic subclassification and molecular profiling allows investigation of targeted therapies as (neo-)adjuvant treatment. High-dose brachytherapy, internal radiation therapy, and transarterial chemoembolization are among the interventional treatment options being evaluated for unresectable iCC. Given the multiple options of multidisciplinary management, any treatment strategy should be discussed in a multidisciplinary tumor board and treatment should be directed by a specialized treatment center.

Abstract

Intrahepatic cholangiocarcinoma (iCC) is distinguished as an entity from perihilar and distal cholangiocarcinoma and gallbladder carcinoma. Recently, molecular profiling and histopathological features have allowed further classification. Due to the frequent delay in diagnosis, the prognosis for iCC remains poor despite major technical advances and multimodal therapeutic approaches. Liver resection represents the therapeutic backbone and only curative treatment option, with the functional residual capacity of the liver and oncologic radicality being deciding factors for postoperative and long-term oncological outcome. Furthermore, in selected cases and depending on national guidelines, liver transplantation may be a therapeutic option. Given the often advanced tumor stage at diagnosis or the potential for postoperative recurrence, locoregional therapies have become increasingly important. These strategies range from radiofrequency ablation to transarterial chemoembolization to selective internal radiation therapy and can be used in combination with liver resection. In addition, adjuvant and neoadjuvant chemotherapies as well as targeted therapies and immunotherapies based on molecular profiles can be applied. This review discusses multimodal treatment strategies for iCC and their differential use.

Surgical management of intrahepatic cholangiocarcinoma

INTRODUCTION

Intrahepatic cholangiocarcinoma (ICC) incidence continues to rise worldwide, and overall survival remains poor. Complete surgical resection remains the only opportunity for cure in patients with ICC yet only one-third of patients present with resectable disease.

AREAS COVERED

While the low incidence rate of ICC hinders accrual of patients to large, randomized control trials, larger database and long-term institutional studies provide evidence to guide surgical management of ICC. These studies demonstrate feasibility, safety, and efficacy of aggressive surgical management in appropriately selected patients with ICC. Recent advances in the management of ICC, with a focus on surgical considerations, are reviewed.

EXPERT OPINION

Historically, little progress has been made in the management of ICC with stagnant mortality rates and poor long-term outcomes. However, regionalization of care to centers with experienced multidisciplinary teams, advances in minimally invasive surgical techniques, discovery and development of targeted and immunotherapy agents, and combination locoregional and systemic therapies offer signs of progress in the management of ICC.

Challenges and Opportunities for Treating Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is one of the rarest and most aggressive types of cancer. The symptoms of ICC patients can be vague, leading to late diagnosis and dismal prognosis. In this review, we investigated the treatment options for ICC, as well as ways to overcome challenges in identifying and treating this disease. Imaging remains the gold standard to diagnose ICC. Patients are staged based on the tumor, nodes and metastases (TNM) staging system. Patients eligible for surgical resection should undergo surgery with curative intent with the goal of microscopically disease-free margins (R0 resection) along with lymphadenectomy. Minimal invasive surgery (MIS) and liver transplantation have recently been offered as possible ways to improve disease outcomes. ICC recurrence is relatively common and, thus, most patients will need to be treated with systemic therapy. Several clinical trials have recently investigated the use of neoadjuvant (NT) and adjuvant therapies for ICC. NT may offer an opportunity to downsize larger tumors and provide patients, initially ineligible for surgery, with an opportunity for resection. NT may also treat occult micro-metastatic disease, as well as define tumor biology prior to surgical resection, thereby decreasing the risk for early postoperative recurrence. Adjuvant systemic therapy may improve outcomes of patients with ICC following surgery. Ongoing clinical trials are investigating new targeted therapies that hold the hope of improving long-term outcomes of patients with ICC.

Proposed modification of the eighth edition of the AJCC staging system for intrahepatic cholangiocarcinoma

BACKGROUND

To improve the prognostic accuracy of the 8th edition of the American Joint Committee on Cancer (AJCC) staging system for intrahepatic cholangiocarcinoma (ICC) with establishment and validation of a modified TNM (mTNM) staging system.

METHODS

Data on patients who underwent curative-intent resection for ICC was collected from 15 high-volume centers worldwide (n = 643). An external validation dataset was obtained from the SEER registry (n = 797). The mTNM staging system was proposed by redefining T categories, and incorporating the recently proposed N status as N0 (no lymph node metastasis [LNM]), N1 (1-2 LNM) and N2 (≥3 LNM).

RESULTS

The 8th AJCC TNM staging system failed to stratify overall survival (OS) of stage II versus IIIA, stage IIIB versus IV, as well as overall stage III versus IV among all patients from the two databases, as well as stage I versus II, and stage III versus III among patients who had ≥6 LNs examined. There was a monotonic decrement in survival based on the proposed mTNM staging classification among patients derived from both the multi-institutional (Median OS, stage I 69.8 vs. II 37.1 vs. III 18.9 vs. IV 16.4 months, all p < 0.05), and SEER (Median OS, stage I 87.0 vs. II 29.3 vs. III 17.7 vs. IV 14.2 months, all p < 0.05) datasets, which was also verified among patients who had ≥6 lymph node harvested from both databases.

CONCLUSION

The modified TNM staging system for ICC using the new T and N definitions provided an improved means to stratify patients relative to long-term OS versus the 8th AJCC staging.

Predicting Lymph Node Metastasis in Intrahepatic Cholangiocarcinoma

BACKGROUND

The objective of the current study was to develop a model to predict the likelihood of occult lymph node metastasis (LNM) prior to resection of intrahepatic cholangiocarcinoma (ICC).

METHODS

Patients who underwent hepatectomy for ICC between 2000 and 2017 were identified using a multi-institutional database. A novel model incorporating clinical and preoperative imaging data was developed to predict LNM.

RESULTS

Among 980 patients who underwent resection of ICC, 190 (19.4%) individuals had at least one LNM identified on final pathology. An enhanced imaging model incorporating clinical and imaging data was developed to predict LNM ( https://k-sahara.shinyapps.io/ICC_imaging/ ). The performance of the enhanced imaging model was very good in the training data set (c-index 0.702), as well as the validation data set with bootstrapping resamples (c-index 0.701) and outperformed the preoperative imaging alone (c-index 0.660). The novel model predicted both 5-year overall survival (OS) (low risk 48.4% vs. high risk 18.4%) and 5-year disease-specific survival (DSS) (low risk 51.9% vs. high risk 25.2%, both p < 0.001). When applied among Nx patients, 5-year OS and DSS of low-risk Nx patients was comparable with that of N0 patients, while high-risk Nx patients had similar outcomes to N1 patients (p > 0.05).

CONCLUSION

This tool may represent an opportunity to stratify prognosis of Nx patients and can help inform clinical decision-making prior to resection of ICC.

Is It Time to Consider Laparoscopic Hepatectomy for Intrahepatic Cholangiocarcinoma? A Meta-Analysis

OBJECTIVES

The role of laparoscopic hepatectomy (LH) for intrahepatic cholangiocarcinoma (ICC) remains indefinite, though the utilization of this minimally invasive approach has been increasing for ICC. We herein performed a meta-analysis to investigate this issue.

METHODS

Six retrospective studies including 384 patients who had undergone LH and 2147 patients who had undergone open hepatectomy (OH) for ICC were included. The fixed-effects or random-effects models were utilized for data analysis.

RESULTS

Compared with patients who had undergone OH for ICC, patients who had undergone LH for ICC experienced more R0 resections (81.6 versus 73.8%, risk ratio (RR) = 1.08, 95% confidence interval (CI) 1.02-1.14; P = 0.008) but less major hepatectomies (37.7 versus 54.2%, RR = 0.69, 95% CI 0.60-0.79; P < 0.0001), less lymph node dissections (38.0 versus 61.5%, RR = 0.62, 95% CI 0.54-0.70; P < 0.0001), and smaller tumor size resected (4.14 versus 4.94 cm, weighted mean difference = - 0.80 cm, 95% CI - 1.38 to - 0.22 cm; P = 0.007). No significant difference was observed in other perioperative results (all P > 0.05) or overall survival (hazard ratio (HR) = 1.38, 95% CI 0.63-3.02; P = 0.43).

CONCLUSIONS

LH has comparable safety, feasibility, and oncological efficacy to that of OH for ICC and has superiority in R0 resection over OH. It may be time to consider LH for ICC only if a more thorough effort on lymph node dissection is undertaken in selective patients at experienced centers.

Prognostic significance of and risk prediction model for lymph node metastasis in resectable intrahepatic cholangiocarcinoma: do all require lymph node dissection?

BACKGROUND

Lymph node (LN) metastasis portends a worse prognosis following resection of intrahepatic cholangiocarcinoma (ICC); however, lymphadenectomy is not routinely performed, as its role remains controversial. Herein, we developed a risk model for LN metastasis by identifying its predictive factors and assessed a subset of patients who might not benefit from LN dissection (LND).

METHODS

210 patients who underwent curative-intent surgery for ICC were retrospectively reviewed. A preoperative risk model for LN metastasis was developed following identification of its preoperative predictive factors using the recursive partitioning method.

RESULTS

In the multivariable analysis, CA 19-9 level of >120 U/mL, an enlarged LN on computed tomography, and a tumor location abutting the Glissonean pedicles were independent predictors of LN metastasis. The preoperative risk model classified the patients according to their risk: high, intermediate, and low risks at a rate of LN metastasis on final pathology of 60.9%, 35%, and 2.3%, respectively. In the subgroup analysis among the low-risk patients, performance of LND had no survival advantage over non-performance of LND.

CONCLUSION

Routine LND for preoperatively diagnosed ICC should be recommended to patients at an intermediate and a high risk of developing LN metastasis but may be omitted for low-risk patients.

Liver resection and transplantation for intrahepatic cholangiocarcinoma

The incidence of intrahepatic cholangiocarcinoma (iCCA) is increasing worldwide. Although several advances have been made in the past decades to better understand this complex malignancy and to develop new treatment strategies, the prognosis of iCCA remains dismal. Liver resection (LR) is the mainstay of treatment but only a minority of patients are amenable to surgery. In most cases, patients with iCCA will require a major hepatectomy for complete resection of the tumour. This may be contraindicated or increase the surgical burden in patients with chronic liver disease and small remnant liver volume. Lymphadenectomy with a minimal harvest of 6 lymph nodes is considered adequate, as microscopic nodal metastases have been shown in more than 40% of patients. Current 5-year overall survival following LR is in the range of 25%-40%. For locally advanced disease not amenable to upfront LR, neoadjuvant locoregional therapies may be used with the aim of converting these patients to resectability or even to transplantation in well-selected cases. Recent studies have shown that liver transplantation (LT) might be a treatment option for patients with unresectable very-early iCCA (i.e. ≤2 cm), with survival outcomes comparable to those of hepatocellular carcinoma. In patients with unresectable, advanced tumours, confined to the liver who achieve sustained response to neoadjuvant treatment, LT may be considered an option within prospective protocols. The role of adjuvant therapies in iCCA is still under debate. Herein, we review the recent advances in the surgical treatment of iCCA and examine its correlation with locoregional therapies, adjuvant and neo-adjuvant strategies.

Number and Station of Lymph Node Metastasis After Curative-intent Resection of Intrahepatic Cholangiocarcinoma Impact Prognosis

OBJECTIVES

To determine the prognostic implication of the number and station of LNM, and the minimal number of LNs needed for evaluation to accurately stage patients with intrahepatic cholangiocarcinoma (ICC).

BACKGROUND

Impact of the number and station of LNM on long-term survival, and the minimal number of LNs needed for accurate staging of ICC patients remain poorly defined.

METHODS

Data on patients who underwent curative-intent resection for ICC was collected from 15 high-volume centers worldwide. External validation was performed using the SEER registry. Primary outcomes included overall (OS), disease-specific, and recurrence-free survival.

RESULTS

Among 603 patients who underwent curative-intent resection, median and 5-year OS were 30.6 months and 30.4%. Patients with 1 or 2 LNM had comparable worse OS versus patients with no nodal disease (median OS, 1 LNM 18.0, 2 LNM 20.0 vs no LNM 45.0 months, both P < 0.001), yet better OS versus patients with 3 or more LNM (median OS, 1-2 LNM 19.8 vs ≥3 LNM 16.0 months, P < 0.01). On multivariable analysis, a proposed new nodal staging with N1 (1-2 LNM) (Ref. N0, HR 2.40, P < 0.001) and N2 (≥3 LNM) [Ref. N0, hazard ratio (HR) 3.85, P < 0.001] categories were independently associated with incrementally worse OS. Patients with no nodal metastasis, 1-2 LNM and ≥3 LNM also had an increasingly worse disease-specific survival, and recurrence-free survival (both P < 0.05). Total number of LNs examined ≥6 had the greatest discriminatory power relative to OS among patients with 1-2 LNM, and patients with ≥3 LNM in both the multi-institutional (area under the curve 0.780) and SEER database (area under the curve 0.820) (n = 1036). Among patients who underwent an adequate regional lymphadenectomy (total number of LNs examined ≥6), LNM beyond the HDL was associated with worse OS versus LNM within the HDL only (median OS, 14.0 vs 24.0 months, HR 2.41, P = 0.003).

CONCLUSION

Standard lymphadenectomy of at least 6 LNs is strongly recommended and should include examination beyond station 12 to have the greatest chance of accurate staging. The proposed new nodal staging of N0, N1, and N2 should be considered to stratify outcomes among patients after curative-intent resection of ICC.