Promising role of liver transplantation in patients with combined hepatocellular-cholangiocarcinoma: a propensity score matching analysis

Update on the Diagnosis and Treatment of Combined Hepatocellular Cholangiocarcinoma

Combined hepatocellular-cholangiocarcinoma (cHCC-CCA) is a unique type of liver tumor that contains both hepatocellular carcinoma and cholangiocarcinoma components within a single tumor. The fifth edition of the World Health Organization classification provides a definition and diagnostic criteria for cHCC-CCA. However, the heterogeneous histomorphology and presentation resulting from variation of the proportion of each component poses challenges for clinical diagnosis and treatment. A diagnosis of cHCC-CCA may be suggested by the synchronous elevation of serum tumor markers for hepatocellular carcinoma and cholangiocarcinoma, a mixed enhancement pattern on imaging, and a discrepancy between the elevation of tumor marker and the imaging enhancement pattern. Histopathological examination using hematoxylin and eosin staining is considered the gold standard for diagnosing cHCC-CCA, and comprehensive examination of resection or biopsy specimens is crucial for an accurate diagnosis. Currently, there is no standard treatment for cHCC-CCA, and surgery is the mainstay. Anatomic hepatectomy with lymphadenectomy is among the recommended surgical procedures. The role of liver transplantation in the management of cHCC-CCA is still uncertain. Transarterial chemoembolization may be effective for unresectable cHCC-CCA, particularly for hypervascular tumors. However, the available evidence does not support systemic therapy for advanced cHCC-CCA. The prognosis of cHCC-CCA is generally poor, and there is no established staging system. Further research is needed to better understand the histogenesis and clinical management of cHCC-CCA. This review provides an overview of the current literature on cHCC-CCA with a focus on its clinical characteristics, pathological diagnosis, and management.

Liver transplantation versus resection for patients with combined hepatocellular cholangiocarcinoma: A retrospective cohort study

Background

Combined hepatocellular cholangiocarcinoma (CHC) is a rare primary liver cancer, and whether liver transplantation should be implemented among CHC patients is still controversial. We intend to conduct a retrospective cohort study based on the Surveillance, Epidemiology, and End Results (SEER) database to investigate the prognosis of liver transplantation vs. liver resection among CHC patients.

Methods

Patients diagnosed with CHC (ICD-O-3:8180/3) and treated with transplantation or hepatectomy were extracted from the SEER database (2000-2018). We utilized Propensity Score Matching to control confounding bias. Kaplan-Meier curve was used for survival analysis, and Cox regression was used to find independent factors associated with prognosis.

Results

We identified 123 (transplantation: 49; resection: 74) patients with CHC who were treated between 2004 and 2015. In the entire cohort, survival analysis demonstrated transplantation group was associated with better overall survival and cancer-specific survival (log-rank p = 0.004 and p = 0.003, respectively). In addition, liver transplantation still conferred better overall and cancer-specific survival than liver resection after Propensity Score Matching (log-rank p = 0.024 and p = 0.048, respectively). However, this advantage didn't appear in the subgroup, regardless of whether the tumor size was greater than 3 cm or not. (≤3 cm: OS log-rank p = 0.230, CSS log-rank p = 0.370; >3 cm: OS log-rank p = 0.110, CSS log-rank p = 0.084). Multivariate analysis validated the finding that liver transplantation was a protective factor for overall survival (HR = 0.55 [0.31-0.95], p = 0.032).

Conclusions

Liver transplantation may be an option in individuals with CHC and should be taken into consideration due to its advantages in terms of overall survival and cancer-specific survival. However, a sizable sample is required for future studies to determine which subset of CHC patients may benefit more from liver transplantation.

Research trends in cholangiocarcinoma treatments during the last 3 decades

Background

Over the past 30 years, numerous studies have focused on the treatment of cholangiocarcinoma (CCA), and these treatments have greatly evolved.

Objectives

To better understand the research trends, we evaluated the most influential publications and attempted to identify their characteristics using bibliometric methods.

Methods

The most influential publications were identified from the Clarivate Analytics Web of Science Core Collection database. The general characteristics of included papers were identified, and the research trends were explored via the bibliometric method.

Results

The average total number of citations for of the listed publications were 312 (range from 165 to 1922). The highest number of papers were published during period II (2001-2010, n = 50), followed by period III (2011-2020, n = 28), and period I (1991-2000, n = 22). The United States and Germany have made remarkable achievements in this field. Institutionally, Mayo Clinic and Memorial Sloan-Kettering Cancer Center were the leading institutions, with Blumgart and Zhu from the United States being the most influential authors. Close collaboration was established between the leading countries, institutions, and authors. The Annals of Surgery contributed the most to the papers with the highest total number of citations. Surgery predominated during period I (n = 14, 63.6%), with a gradual decline occurring during periods II (n = 19, 41.3%, P = 0.085) and period III (n = 3, 9.4%, P = 0.002). Contrastingly, the number of publications related to systemic therapy has increased significantly since period II and peaked in period III.

Conclusions

Surgery remains the most important treatment for CCA. However systemic therapy has become a research and clinical application hotspot. These findings will contribute to the translation of treatments for CCA and provide researchers with relevant research directions.

Propensity-matched analysis of patients with intrahepatic cholangiocarcinoma or mixed hepatocellular-cholangiocarcinoma and hepatocellular carcinoma undergoing a liver transplant

BACKGROUND

Cholangiocarcinoma (CC) is a rare tumor that arises from the epithelium of the bile ducts. It is classified according to anatomic location as intrahepatic, perihilar, and distal. Intrahepatic CC (ICC) is rare in patients with cirrhosis due to causes other than primary sclerosing cholangitis. Mixed hepatocellular carcinoma-CC (HCC-CC) is a rare neoplasm that shows histologic findings of both HCC and ICC within the same tumor mass. Due to the difficulties in arriving at the correct diagnosis, patients eventually undergo liver transplantation (LT) with a presumptive diagnosis of HCC on imaging when, in fact, they have ICC or HCC-CC.

AIM

To evaluate the outcomes of patients with intrahepatic cholangiocarcinoma or mixed hepatocellular-cholangiocarcinoma on pathological examination after liver transplant.

METHODS

Propensity score matching was used to analyze tumor recurrence (TR), overall mortality (OM), and recurrence-free survival (RFS) in LT recipients with pathologically confirmed ICC or HCC-CC matched 1:8 to those with HCC. Progression-free survival and overall mortality rates were computed with the Kaplan-Meier method using Cox regression for comparison.

RESULTS

Of 475 HCC LT recipients, 1.7% had the diagnosis of ICC and 1.5% of HCC-CC on pathological examination of the explant. LT recipients with ICC had higher TR (46% vs 11%; P = 0.006), higher OM (63% vs 23%; P = 0.002), and lower RFS (38% vs 89%; P = 0.002) than those with HCC when matched for pretransplant tumor characteristics, as well as higher TR (46% vs 23%; P = 0.083), higher OM (63% vs 35%; P = 0.026), and lower RFS (38% vs 59%; P = 0.037) when matched for posttransplant tumor characteristics. Two pairings were performed to compare the outcomes of LT recipients with HCC-CC vs HCC. There was no significant difference between the outcomes in either pairing.

CONCLUSION

Patients with ICC had worse outcomes than patients undergoing LT for HCC. The outcomes of patients with HCC-CC did not differ significantly from those of patients with HCC.