Clinical Significances of Preoperative Classification of Intrahepatic Cholangiocarcinoma: Different Characteristics of Perihilar vs. Peripheral ICC

Abstract

Abstract. Background: The aim of this study was to evaluate the clinical significance of preoperative classification of intrahepatic cholangiocarcinoma (ICC) into perihilar and peripheral types using dynamic computed tomography (CT). Patients and MethodsEven though intrahepatic cholangiocarcinoma (ICC) is a relatively rare disease, it is the second most common primary liver malignant tumor after hepatocellular carcinoma (HCC), and has a relatively highly prevalence in Asia and the U.S.A., with over 1/100,000 population ratio (1). In addition, the incidence of ICC has rapidly increased by 165% in the last 30 years in the U.S.A., and surgical resection remains the only treatment available with curative intent (2). However, surgical results for ICC remain unsatisfactory with a five-year survival rate of 58%, even in R0 resected cases (3). Lymph node metastasis has been reported to be the most significant poor prognostic factor for ICC, and extended lymphadenectomy does not have a survival impact (3-5). While lymphatic invasion is the major mode of cancer spreading for ICC (6), intrahepatic metastasis caused by venous spread is another important mode of spreading (4, 5).ICCs are composed of heterogenous carcinomas arising from different anatomical liver sites. ICC arises from the epithelial cells of the biliary tree, from either intrahepatic large bile ducts or smaller bile ducts, such as the septal and interlobular ducts. Ebata et al. clearly defined as perihilar cholangiocarcinoma, a tumor involving the hilar bile duct with a liver mass (7). We proposed the classification of ICC based on the pathological findings in perihilar large duct type and peripheral small duct type subtypes (8, 9). Perihilar ICC arises from the peribiliary gland, and peripheral ICC from the canals of Hering (9); the two subtypes have different molecular and clinicopathological characteristics and patient prognoses (8, 9). However, pathological classification currently contributes only whether or not to plan adjuvant chemotherapy. Therefore, it is important to construct a preoperative classification that can be used to modify surgical plans and so on to improve patients' prognosis for ICC. 6563

Prognostic factors predicting survival rate over 10 years of patients with intrahepatic cholangiocarcinoma after hepatic resection

“…It is widely acknowledged that the curative treatment of IHCC is surgical resection. Despite the surgical advances and risk factors for IHCC, the clinical outcome after resection is still dismal [13,14]. Consequently, the 5-year survival rate in our institution was 33.3%, which was comparable to the previously reported survival rates [11,13,15,16].…”

Efficacy of surgical management for recurrent intrahepatic cholangiocarcinoma: A multi-institutional study by the Okayama Study Group of HBP surgery

“…The hilar type ICCs originated from intrahepatic large biliary ducts are likely to show aggressive course with metastatic potential. Though tumor localization could be classified according to radiological findings in this study, classification based on radiological findings has been reported to accurately reflect histomorphological typing [33,34]. In fact, hilar type ICC, defined by radiological localization in this study, showed higher recurrence rate and poorer survival than peripheral type.…”

Predictors of Cure of Intrahepatic Cholangiocarcinoma After Hepatic Resection

“…Surgical techniques. The details of our surgical techniques and the follow-up methods have been reported (1,9,12,13). Major hepatic resection (HR) with bile duct resection was performed when bile duct invasion of ICC was suspected to have affected the first hepatic duct.…”

“…However, the surgical outcomes for ICC remain unsatisfactory with a 5-year survival rate of 23.6-35% (1,4,7,8) and 58% even after R0 resection (1,9). The rate of recurrence was also reported to be high, at 53-71% (4,10,11).…”