%0 Journal Article %T Klatskin-Like Lesions %A M. P. Senthil Kumar %A R. Marudanayagam %J HPB Surgery %D 2012 %I Hindawi Publishing Corporation %R 10.1155/2012/107519 %X Hilar cholangiocarcinoma, also known as Klatskin tumour, is the commonest type of cholangiocarcinoma. It poses unique problems in the diagnosis and management because of its anatomical location. Curative surgery in the form of major hepatic resection entails significant morbidity. About 5¨C15% of specimens resected for presumed Klatskin tumour prove not to be cholangiocarcinomas. There are a number of inflammatory, infective, vascular, and other pathologies, which have overlapping clinical and radiological features with a Klatskin tumour, leading to misinterpretation. This paper aims to summarise the features of such Klatskin-like lesions that have been reported in surgical literature. 1. Introduction Hilar cholangiocarcinoma, also known as Altemeier-Klatskin tumour is a primary malignancy of the liver occurring at the confluence of the bile ducts, first reported by Altemeier et al. in 1957 and characterised by Klatskin in 1965 [1, 2]. Occurring within 2£¿cm of the hilar confluence, it accounts for about 50¨C70% of all cholangiocarcinomas [3]. Resection and in selected patients, transplantation offers the best chance of cure in Klatskin tumours. Hence, early diagnosis is vital for a radical surgical approach to be feasible and effective. Equally, it is ideal, though not always possible, to have an established diagnosis of cancer or a strong probability of malignancy before embarking on a radical liver resection in view of the potential morbidity and mortality. Klatskin tumours have to be differentiated from a number of benign pathologies and some malignant lesions that mimic the clinical presentation and the radiological appearances (Table 1). These have been variously called ¡°Klatskin-mimicking lesions,¡± ¡°the malignant masquerade,¡± and ¡°pseudo-Klatskin tumours¡± [4, 5]. In most large series of hilar strictures, operated on, with a preoperative diagnosis of cholangiocarcinoma (CCA), the rate of benign lesions on final histopathology ranges from 5 to 15%, reaching up to a third in some reports (Table 1) [6¨C10]. Table 1: Incidence of Klatskin-like lesions. Hilar cholangiocarcinoma has three morphological types: periductal infiltrative, polypoid, and exophytic (mass forming), depending on the predominant pattern of spread in relation to the duct wall. Infiltrating CCA is the commonest type of hilar CCA (70%) and typically appears as a focal thickening of bile duct with hyperattenuation on imaging. Polypoid CCA appears as an intraluminal hypoattenuating lesion. Exophytic hilar CCA is typically seen as a hypodense mass lesion with rim enhancement. Tumour markers %U http://www.hindawi.com/journals/hpb/2012/107519/