Intra-hepatic and extra-hepatic cholangiocarcinoma: New insight into epidemiology and risk factors

Abstract

Cholangiocarcinoma (CCA) is a malignant tumour that arises from biliary epithelium at any portion of the biliary tree. CCA is currently classified as intra-hepatic or extra-hepatic CCA (EH-CCA). Recent evidences suggest that intra-hepatic CCA (IH-CCA) and EH-CCA are biologically different cancers, giving further support to a number of recent epidemiological studies showing large differences in terms of incidence, mortality and risk factors. The purpose of this manuscript is to review recent literature dealing with the descriptive epidemiology and risk factors of CCA with a special effort to compare IH- with EH-CCA.

Cholangiocarcinoma: current knowledge and future perspectives consensus statement from the European Network for the Study of Cholangiocarcinoma (ENS-CCA)

“…Occult HBV infection is an emerging risk factor for iCCA 29 . The increased incidence of iCCA, registered at the end of the past century, has been linked with the burden of HCV infection 29,30 . Other studies also demonstrate an association between metabolic syndrome and CCA, which could lead to increased incidence in Western countries given the rising prevalence of obesity 31,32 .…”

“…This process might be favoured by local intrahepatic accumulation of bile acids, even in the absence of net cholestasis 36 . Several toxic and environmental factors are known or suspected to be Nature Reviews | Gastroenterology & Hepatology 1,5,30 . Data refer to the period 1971-2009.…”

Evaluation and validation of suitable reference genes for reverse transcription-quantitative polymerase chain reaction studies in cholangiocarcinoma patients and cell lines

“…To the best of our knowledge, there have been no systematic comparisons performed concerning the stability of commonly-used reference genes in CCA tissues and cell lines. Early diagnosis of CCA is challenging, and it is problematic to achieve a satisfactory therapeutic effect in patients (2,3). In addition, evaluating the prognosis of patients with CCA is inaccurate.…”

“…In America, the incidence of this disease is 1.4-1.7 per 100,000 individuals (1,2), whilst Chinese patients with CCA account for >55% of cases worldwide (3). Complete tumor resection is considered to be the most efficient therapy for CCA; however, only 10% of patients are regarded as candidates for surgical resection as CCA may be highly malignant and progress rapidly, making surgical resection no longer an option for the majority of patients upon diagnosis (1).…”

Association of NRF2 Polymorphism with Cholangiocarcinoma Prognosis in Thai Patients

“…However, in further analysis in the intrahepatic CCA, only SNP rs6726395, but not others, was associated with the prognosis of CCA. CCA is a collection of intrahepatic and extrahepatic CCA, and these two types are suggested to be biologically different cancers (Cardinale et al, 2010). Several epidemiological studies indicate that the incidence and mortality of intrahepatic CCA is progressively increasing worldwide, whereas those of extrahepatic CCA seem to be stable or decreasing (Khan et al, 2008;Singal et al, 2011).…”