Ki Tae Jang

Ampullary (AMP) carcinomas comprise a heterogeneous group of cancers lacking adequate subcategorization. In the present study, 249 strictly defined primary AMP carcinomas (ACs) identified in 1469 malignant pancreatoduodenectomy specimens were analyzed for defining features. Gross and microscopic findings were used to determine tumor epicenter and extent of preinvasive component. ACs were classified into 4 distinct subtypes based on location: (1) Intra-AMP (25%): Invasive carcinomas arising in in

Information on the clinicopathologic characteristics of invasive carcinomas arising from mucinous cystic neoplasms (MCNs) is limited, because in many early studies they were lumped and analyzed together with noninvasive MCNs. Even more importantly, many of the largest prior studies did not require ovarian-type stroma (OTS) for diagnosis. We analyzed 178 MCNs, all strictly defined by the presence of OTS, 98% of which occurred in perimenopausal women (mean age, 47 y) and arose in the distal pancre

Abundant recent data suggest that sessile serrated adenoma/polyp (SSA/P) is an early precursor lesion in the serrated pathway of carcinogenesis. It is believed that SSA/Ps develop cancer by an SSA/P-dysplasia-carcinoma sequence. Hyperplastic polyps (HPs) share some histologic and molecular characteristics with SSA/P, but it is unclear whether SSA/Ps are derived from HPs or whether they develop by a different pathogenetic pathway. Previous studies have shown that serrated polyps from Korean patie

AIMS: To improve the characterization of intraductal papillary neoplasm of the bile duct (IPNB) and mucinous cystic neoplasm of the liver (MCN-L). METHODS AND RESULTS: A retrospective review of pathology archives (1999-2011) in our three institutions identified cases of IPNB (n = 138) and MCN-L (n = 54). The IPNB/MCN-L ratio was 5.7:1 at Samsung Medical Centre in Seoul, which was significantly higher than those at the University of Washington Medical Center in Seattle (1:3.0) and King's College

Micropapillary carcinoma (MPC) of the stomach is a rare, newly recognized entity, and only 2 patients with this histology have been reported. We investigated clinicopathologic features, expression of mucin (MUC2, MUC5AC, MUC6, CD10) and cytokeratin profiles (CK7 and CK20), epidermal growth factor receptors (EGFR and HER2), prognostic markers (p53 and Ki-67), and outcomes in 11 MPCs of the stomach. The proportion of MPC component ranged from 5% to 70%. Micropapillary features were often found at

Intraductal tubulopapillary neoplasm (ITPN) has been recently reported in pancreas. We experienced an unusual intraductal growing bile duct tumor, which showed the same histopathologic and immunostaining profiles as ITPN of pancreas. A 72-year-old female patient visited hospital due to intrahepatic stone. The hilar bile duct tumor was detected and incidental lung mass was found in systemic evaluation. The histopathologic finding of the two biopsy lesions was different. The lung tumor was an aden

According to the current AJCC staging system, the T stage of distal extrahepatic bile duct carcinoma (EBD) is classified according to the extent of the tumor within or beyond the bile duct wall. However many invasive carcinoma accompany stromal desmoplasia that obscure lower boundary of bile duct wall; it is frequently difficult to clearly define the extent of tumors using the current T classification system. In this study, we validated an alternative T classification system by depth of invasion

BACKGROUND: Intraductal papillary neoplasm of the bile duct (IPNB) is a relatively rare disease and is known as one of the premalignant lesions in the biliary tract. The concept of IPNB has changed through numerous studies and is still evolving. As a lesser studied clinical entity compared with its pancreatic counterpart, intraductal papillary mucinous neoplasm, IPNB has been described in many similar terms, including biliary papillomatosis, biliary intraductal papillary-mucinous neoplasm, and p

Aberrant expression of Sonic hedgehog (Shh) has been reported in many human cancers including ductal carcinoma of the pancreas. The intraductal papillary mucinous tumor (IPMT) has been considered as one of the precursor lesions of invasive ductal carcinoma of the pancreas. Shh expression in pancreatic IPMT has not been reported. We investigated an immunohistochemical (IHC) expression of Shh in 55 cases of pancreatic IPMT. We analyzed the IHC expression of Shh in the following histologic grades o

CONTEXT: -The identification of a precursor lesion is important to understanding the histopathologic and genetic alterations in carcinogenesis. There are a plethora of terminologies that describe precursor lesions of the pancreatobiliary tract, ampulla of Vater, and gallbladder. The current terminologies for precursor lesions may make it difficult to understand the tumor biology. Here, we propose the concept of tumoral and flat intraepithelial neoplasia to improve our understanding of precursor

BACKGROUND: Mutations in the telomerase reverse transcriptase (TERT) promoter region have been proposed as novel mechanisms for the transcriptional activation of telomerase. Two recurrent mutations in the TERT promoter, C228T and C250T, are prognostic biomarkers. Herein, we directly compared the commercially available iTERT PCR kit with NGS-based deep sequencing to validate the NGS results and determine the analytical sensitivity of the PCR kit. METHODS: Of the 2032 advanced solid tumors diagnos