Search Results (7)

Benign biliary tumors and precursor neoplasms of the biliary tract are a heterogeneous group of uncommon neoplasms with significant clinical and diagnostic implications. Their importance lies in their variable malignant potential and morphological and molecular similarities to pancreatic neoplasms. The sixth edition of the World Health Organization Classification of Digestive System Tumours (WHO DST6), published online in 2026, introduced major revisions to the classification of these entities. According to WHO DST6, benign tumors and precursor neoplasms of the liver and intrahepatic bile ducts include bile duct adenoma, biliary adenofibroma, and mucinous cystic neoplasm, whereas those of the gallbladder and extrahepatic bile ducts include biliary intraepithelial neoplasia, intraductal papillary neoplasm of the bile ducts, intraductal tubulopapillary neoplasm of the bile ducts, intraductal oncocytic papillary neoplasm of the bile ducts, and mass-forming intracholecystic neoplasm. Despite these advances, their histological and molecular heterogeneity continues to pose significant diagnostic challenges, particularly in distinguishing them from malignant biliary tumors on limited biopsy specimens and in recognizing early invasive lesions. This review summarizes the clinicopathological and molecular features of benign biliary tumors and precursor neoplasms, emphasizing differential diagnosis and key updates introduced in WHO DST6. Full article

Background and Clinical Significance: Synchronous gastrointestinal tumors are exceptionally rare, particularly when combining histologically distinct benign and malignant components. Schwannomas represent uncommon mesenchymal tumors of the gastrointestinal tract, most frequently arising in the stomach, while rectal localization is exceedingly unusual. Papillary adenocarcinoma of the gallbladder is an aggressive malignant entity derived from intracholecystic papillary–tubular neoplasms (ICPNs). The coexistence of these two unrelated neoplasms has not been previously reported, making this case of dual tumor pathogenesis clinically and academically significant. Case Presentation: A 68-year-old female was admitted for surgical management of grade IV uterovaginal prolapse. Preoperative imaging incidentally revealed a well-circumscribed rectal wall mass and gallstones. A combined abdominopelvic operation was performed, including total hysterectomy with bilateral adnexectomy (Wiart procedure), rectosigmoid resection with colorectal anastomosis, and bipolar cholecystectomy. Intraoperatively, a firm intramural rectal lesion and a friable papillary mass in the gallbladder fundus were identified. Histopathologic examination confirmed a benign rectal schwannoma (S-100 positive, CD117/DOG-1 negative) and a papillary adenocarcinoma of the gallbladder, pT3N0M0, with clear resection margins and no lymphovascular or perineural invasion. The postoperative course was uneventful, and the patient remained disease-free at six-month follow-up. Conclusions: This case represents an exceedingly rare benign–malignant synchronous tumor association. The simultaneous occurrence of rectal schwannoma and gallbladder papillary adenocarcinoma underscores the importance of thorough intraoperative exploration and histopathologic evaluation. Complete resection with negative margins and multidisciplinary follow-up remains crucial for optimal outcomes and contributes to understanding dual tumor pathogenesis within the gastrointestinal tract. Full article

There are several types of microvasculature supplying neoplasms: “newly formed blood vessels” (neoangiogenesis), which are a component of the tumor microenvironment (TME) of invasive carcinoma with wound healing-like reaction; and “pre-existing blood vessels”, which are used as tumor-supplying vessels by neoplasms (co-option vessels) and are likely to develop in hypervascularized organs. We herein review the microvasculature of neoplasms of biliary tract with reference to pre-existing vessels and vessel co-options. In the hepatobiliary system, intrahepatic large and extrahepatic bile ducts (large bile ducts) and the gallbladder as well as hepatic lobules are highly vascularized regions. In large bile ducts, the biliary lining epithelia and underlining capillaries (peribiliary capillary plexus [PCP]) form the biliary epithelia–PCP alignment, whereas the hepatocyte–sinusoid alignment composes hepatic lobules. Cholangiocarcinoma (CCA) and gallbladder carcinoma (GBC) are the main biliary tract carcinomas. CCA is subdivided into distal (d/CCA), perihilar (pCCA), and intrahepatic (iCCA), and iCCA is subdivided into small duct type (SD-iCCA) and large duct type (LD-iCCA). High-grade biliary intraepithelial neoplasm (BilIN), intraductal papillary neoplasm of the bile duct (IPNB), pyloric gland adenoma (PGA), and intracholecystic papillary neoplasm (ICPN) have recently been proposed as the precursors of LD-iCCA, p/dCCA, and GBC. In the large bile ducts and gallbladder, all cases of high-grade BilIN and PGA, about half of IPNB, and one-third of ICPN with less-complicated structure were found to have hijacked the PCP as their supporting vessels (vessel co-option), while p/dCCA, LD-iCCA, and GBC were supplied by neo-angiogenetic vessels associated with fibrous stroma. The intraluminal components of the remaining cases of ICPN and IPNB with complicated structure presented sparse capillaries without fibrous stroma, a unique microvasculature different from that of co-option or neoangiogenesis. Regarding iCCA showing invasion into the hepatic lobules, some SD-iCCAs replaced hepatocytic cords and used pre-existing sinusoids as co-opted vessels. Visualization of pre-existing vessels could be a new pathological tool for the evaluation of malignant progression and of vascular supply in CCAs and its precursors. Full article

Background: Giant gallbladder is an uncommon condition that can result from a benign pathology and rarely presents with malignancy. Intracholecystic papillary–tubular neoplasm (ICPN) is a relatively new entity first described by V. Adsay in 2012 and included in the World Health Classification of Digestive System Tumours in 2019. Intracholecystic papillary-tubular neoplasm is a preinvasive lesion with an incidence of around 1% that may present as four histologic subtypes—biliary, gastric, intestinal, or oncocytic—of which the biliary subtype has the highest risk of associated invasive cancer. Although invasive carcinoma is present in about 50% of cases of ICPN, these patients have a significantly better prognosis than those with usual gallbladder cancer, suggesting that the entities may have distinct biological signatures. Case report: A 77-year-old female presented to the hospital with progressive swelling in the right hemiabdomen, a loss of appetite, and weight loss. MRI highlighted a giant abdominal tumor located in the right hypochondrium and right abdominal flank with liver invasion (segment V). Preoperatively, a gallbladder 25 × 17 cm in size was noted, and the patient underwent radical cholecystectomy. It was surprising to find such a giant malignant gallbladder tumor, diagnosed as invasive poorly cohesive carcinoma associated with ICPN. Discussion: A megacholecyst is a rare discovery. Although most often found in benign pathologies, giant gallbladder cancer can be considered. The neoplastic features and the loco-regional extension of the tumor must be evaluated by imaging scans. Few cases of giant benign gallbladder have been reported in the literature; however, this appeared to be the largest resectable gallbladder carcinoma reported to date according to the literature. Conclusion: The stage of gallbladder neoplasia is not correlated with the size of the gallbladder. Regardless of tumor size, the prognosis seems to be directly related to the stage, morphology, and resectability. Full article

Carcinomas and precursor lesions of the biliary tract belong to a spectrum of pancreatobiliary neoplasms that share common histology and cell lineages. Over the past two decades, preinvasive precursors to biliary tract carcinomas (BTCs) have been identified such as high-grade biliary intraepithelial neoplasm (high-grade BilIN), intraductal papillary neoplasm of bile duct (IPNB) and intracholecystic papillary neoplasm of the gallbladder (ICPN). While a majority of these precursors may arise from the biliary tract mucosa, some originate from the peribiliary glands and Rokitansky-Aschoff sinuses in the walls of the biliary tract. High-grade BilIN is a microscopically identifiable intraepithelial neoplasm of the biliary tract, whereas IPNB and ICPN are grossly visible intraductal or intraluminal preinvasive neoplasms in the bile duct and gallbladder, respectively. These neoplasms show characteristic histologic features according to four cell lineages and two-tiered grading, and show intraepithelial spreading to the surrounding mucosa and involve non-neoplastic glands in the walls of the biliary tract. These precursors are not infrequently associated with stromal invasion, and high-grade BilIN, in particular, are frequently identified in the surrounding mucosa of BTCs. Taken together, it seems likely that progression from these precursors to invasive carcinoma is a major process in biliary carcinogenesis. Full article

Understanding the pathogenesis and carcinogenesis of gallbladder adenocarcinoma is important. The fifth edition of the World Health Organization’s tumor classification of the digestive system indicates three types of preinvasive neoplasm of the gallbladder: pyloric gland adenoma (PGA), biliary intraepithelial neoplasia (BilIN), and intracholecystic papillary neoplasm (ICPN). New terminologies have also been introduced, such as intracholecystic papillary-tubular neoplasm, gastric pyloric, simple mucinous type, and intracholecystic tubular non-mucinous neoplasm (ICTN). Pancreatobiliary maljunction (PBM) poses a markedly high risk for bile duct carcinoma, which was analyzed and investigated mainly by Asian researchers in the past; however, recent studies have clarified a similar significance of biliary carcinogenesis in Western countries as well. In this study, we reviewed and summarized information on three gallbladder neoplastic precursors, PGA, BilIN, and ICPN, and gallbladder lesions in patients with PBM. Full article

Rokitansky-Aschoff sinuses (RAS) are a common imaging finding in gallbladder adenomyomatosis (ADM), often presenting as fundal cystic spaces. Intracholecystic papillary neoplasm (ICPN) is a relatively uncommon pre-invasive tumor of the gallbladder epithelium that rarely involves RAS mucosa. We compare two cases that showed similar fundal cystic spaces resembling RAS, in which Magnetic Resonance Diffusion-Weighted Imaging (MR-DWI) was valuable for detecting (or ruling out) an underlying malignant ICPN. Evidence from the literature overall supports the role of MR-DWI for detecting intracholecystic malignant tissue. Full article