Pathological characterization of intracholecystic papillary neoplasm: A recently proposed preinvasive neoplasm of gallbladder

18 F-FDG PET/CT of Intracholecystic Papillary Neoplasm in Cystic Neck and Duct

ABSTRACT

We report 18 F-FDG PET/CT appearances of intracholecystic papillary neoplasm (ICPN) in the gallbladder neck and duct of a 74-year-old woman with a history of hepatitis B cirrhosis. The lesion presented with a large and sessile soft mass in the neck and duct of gallbladder with obvious glucose metabolism on PET/CT images, which was confirmed pathologically as ICPN (gastric foveolar type) with high-grade intraepithelial neoplasia. ICPN localized in the gallbladder neck and duct is extremely rare, and is easily misdiagnosed as gallbladder carcinoma. Our report aids in the application of PET/CT in the differential diagnosis of ICPN and guiding early surgery.

Papillary Neoplasms of the Gallbladder and Extrahepatic Bile Ducts: A Report of Two Cases With Associated Invasive Carcinoma

Intracholecystic papillary neoplasm (ICPN) of the gallbladder is a macroscopically visible premalignant lesion protruding into the gallbladder lumen, with infrequent association with invasive adenocarcinoma. Intraductal papillary neoplasm of the bile ducts (IPNB) is a non-invasive lesion characterized by intraductal papillary or villous architecture. Both ICPN and IPNB are rare findings in the gallbladder and biliary tract pathology. Diagnosis relies on clinical manifestations, imaging techniques, and comprehensive histological examination. Here, we present two cases: a 63-year-old male with mild abdominal pain found to have a gallbladder mass, diagnosed histologically as ICPN with associated invasive carcinoma; and a 65-year-old female with chronic jaundice and a large tumor mass in the common bile duct, histologically diagnosed as IPNB with associated invasive carcinoma. These cases highlight the importance of a careful and thorough microscopic examination to rule out differential diagnoses and to reveal any potential invasive carcinoma associated with these uncommon lesions.

Intracholecystic papillary neoplasm acquiring malignant characteristics and leading to multiple liver metastases: A case report

The mechanisms underlying the progression of intracholecystic papillary neoplasms (ICPNs) to gallbladder cancer and invasive cancer remain relatively unclear. In the present case, metastatic liver tumors were suspected in an 83-year-old man at presentation; however, the primary tumor was unknown. The patient died shortly thereafter as a result of rapid tumor progression. An autopsy revealed multiple liver, lung, and lymph node metastases. Additionally, a fragile papillary tumor with a high-grade dysplastic epithelium with tubulopapillary morphology and admixed foci of a low-grade dysplastic epithelium were detected at the fundus of the gallbladder. The well-differentiated tubular adenocarcinoma had extensively invaded the wall's granular mucosal surface along with the solitary papillary tumor. Based on pathological findings, a diagnosis of an ICPN with an associated invasive carcinoma was established. This case is novel because it showed that an ICPN can progress aggressively.

Extensively Invasive Gallbladder Cancer from Intracholecystic Papillary Neoplasm Treated with Pylorus-Preserving Pancreaticoduodenectomy and Extended Cholecystectomy: A Case Report and Literature Review

Background

Intracholecystic papillary neoplasm (ICPN) is a rare tumor first classified by the World Health Organization in 2010. ICPN is a counterpart of the intraductal papillary mucinous neoplasm of the pancreas and intraductal papillary neoplasm of the bile duct. Previous reports on ICPN are limited; thus, the diagnosis, surgical intervention, and prognosis are controversial. Here, we report an extensively invasive gallbladder cancer arising in ICPN treated with pylorus-preserving pancreaticoduodenectomy (PPPD) and extended cholecystectomy. Case Presentation. A 75-year-old man presented to another hospital with jaundice for 1 month. Laboratory findings showed elevated total bilirubin, 10.6 mg/dL and carbohydrate antigen 19-9, 54.8 U/mL. Computed tomography showed a well-enhanced tumor located in the distal bile duct and dilated hepatic bile duct. The gallbladder wall was thickened and homogeneously enhanced. Endoscopic retrograde cholangiopancreatography revealed a filling defect in the distal common bile duct, and intraductal ultrasonography showed a papillary tumor in the common bile duct, indicating tumor invasion of the bile duct subserosa. Subsequent bile duct brush cytology revealed adenocarcinoma. The patient was referred to our hospital for surgical treatment and underwent an open PPPD. Intraoperative findings showed a thickened and indurated gallbladder wall, suggesting concurrent gallbladder cancer; thus, the patient subsequently underwent PPPD and extended cholecystectomy. Histopathological findings confirmed gallbladder carcinoma originating from ICPN, which extensively invaded the liver, common bile duct, and pancreas. The patient started adjuvant chemotherapy (tegafur/gimeracil/oteracil) 1 month after surgery and had no recurrence at follow-up after 1 year.

Conclusions

Accurate preoperative diagnosis of ICPN, including the extent of tumor invasion is challenging. To ensure complete curability, the development of an optimal surgical strategy considering preoperative examinations and intraoperative findings is essential.

A Rare Finding of Incidental Intracholecystic Papillary Neoplasm Following Acute Cholecystitis Management

Intracholecystic papillary neoplasm (ICPN) is a grossly visible, mass-forming, noninvasive epithelial neoplasm arising from the mucosa and projecting into the lumen of the gallbladder. ICPN is a lesser-known tumor of the gallbladder lining, which although has a better prognosis compared to gallbladder adenocarcinoma carries the potential for metastatic transformation with spread to other organs. ICPN is found incidentally on imaging or during postop histological evaluation. However, we present a unique case of ICPN that was incidentally diagnosed in a 72-year-old Eastern European woman following cholecystectomy for acute cholecystitis and was missed on preoperative imaging. Follow-up protocols of ICPN are poorly understood and vastly underreported. We discuss this patient's findings in light of current literary evidence available on ICPN and outline future directions for better clinical understanding. We also highlight the need for screening guidelines in light of known risk factors to better understand the natural history of the disease to prevent malignant transformation into invasive gallbladder carcinoma.

Lymph node metastatic status could predict the prognosis of intracholecystic papillary neoplasm of gallbladder

Intracholecystic papillary neoplasm (ICPN) is a non-invasive epithelial tumor that presents as a grossly identifiable mass arising in the mucosa and protruding into the lumen. ICPN is associated with invasive carcinoma. There are few studies on the clinicopathological features of ICPN, including that with invasive carcinoma. We evaluated the clinicopathological characteristics of 42 ICPNs and 41 conventional gallbladder adenocarcinomas (cGBAs). Subserosa or deeper (≥ss) invasion was significantly lower in ICPN (61.9%) than that in cGBA (90.2%) (P=0.004). Cox regression analysis revealed that lymph node metastasis (hazard ratio [HR] [95% confidence interval (CI)]: 2.610 [1.131, 6.024], P=0.025) and positive margin (HR [95% CI]: 5.143 [2.113, 12.516], P<0.001), but not ≥ss invasion (HR [95% CI]: 1.541 [0.479, 4.959], P=0.469), were independent prognostic factors. In addition, there was a significant interaction between histological type and lymph node metastasis (HR [95% CI]: 0.191 [0.042, 0.983], P=0.033). In cGBA, the presence or absence of lymph node metastasis did not affect prognosis; however, ICPN without lymph node metastasis had better prognosis. Therefore, the histological classification of ICPN and cGBA and the pathological evaluation of lymph node metastasis in ICPN are crucial for determining prognosis.

Intraepithelial involvement of non-neoplastic glands in papillary preinvasive neoplasms of the biliary tract: a potential diagnostic pitfall

Intracholecystic papillary neoplasms of the gallbladder (ICPN) and intraductal papillary neoplasms of the bile duct (IPNB) show intramural neoplastic growths in addition to intraluminal papillary or polypoid neoplastic growth. Such intramural growths include intraepithelial involvement of non-neoplastic glands by preinvasive neoplastic epithelia (glandular involvement) as well as stromal invasive carcinoma. A total of 29 ICPN cases and 84 IPNB cases were pathologically examined for their glandular involvement. Glandular involvement was characterized by intramural neoplastic glands (1) showing cytological and phenotypical similarities to intraluminal preinvasive papillary neoplasms and (2) showing reminiscent configurations of non-neoplastic glands, such as (i) a mixture of preinvasive neoplastic epithelia and non-neoplastic epithelia within the same glands, (ii) neoplastic glands close to or within clustered non-neoplastic glands, or (iii) continuous growth of intraluminal preinvasive neoplastic glands into the walls. Such glandular involvement was found in 16 of 29 ICPN and 48 of 84 IPNB, and 15 of the former and 28 of the latter were not associated with invasive carcinoma. Non-invasive ICPN and IPNB with glandular involvement showed a favorable postoperative overall survival (OS). Glandular involvement by preinvasive neoplastic epithelia was frequently found in ICPN and IPNB. Such lesions may be diagnostic pitfalls in ICPN and IPNB referring to invasion. Glandular involvement without invasive carcinoma was not associated with an unfavorable postoperative OS in ICPN and IPNB. Recognition of glandular involvement may thus prevent overestimation of invasive carcinoma in ICPN and IPNB.

The Clinical and Pathologic Features of Intracholecystic Papillary-Tubular Neoplasms of the Gallbladder

Intracholecystic papillary-tubular neoplasm denotes a discrete mucosal-based neoplastic proliferation into the gallbladder lumen. It is diagnosed incidentally during cholecystectomy or radiologically during a workup for abdominal pain. The majority of polypoid lesions in the gallbladder are non-neoplastic; therefore, pathologic examination is the gold standard to establish this diagnosis. Intracholecystic papillary-tubular neoplasm is considered as premalignant, although associated invasive carcinomas may be present in the specimen. Invasive carcinoma arising from intracholecystic papillary-tubular neoplasm have a better prognosis than de novo gallbladder carcinomas. The pathology of intracholecystic papillary-tubular neoplasm, including the challenges involved in the diagnosis of this entity, is discussed.

Precursor Lesions of Gallbladder Carcinoma: Disease Concept, Pathology, and Genetics

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.

Pathological features of pyloric gland adenoma of the gallbladder in comparison with gastric subtype of intracholecystic papillary neoplasm

BACKGROUND AND AIMS

Pyloric gland adenoma (PGA) of the gallbladder is a polypoid, preinvasive epithelial neoplasm composed of uniform back-to-back, pyloric glands in a tubular configuration. Intracholecystic papillary neoplasm (ICPN), another preinvasive grossly visible neoplasm of the gallbladder, is subdividable into four subtypes, including gastric subtype. In this study, PGA was reappraised referring to gastric subtype of ICPN (gICPN).

MATERIALS AND METHODS

PGA and gICPN pathologically defined by WHO 2019 classification were surveyed in a total of 104 cases of gallbladder epithelial neoplasms of our Hospital (2002 January to 2021 May) and were pathologically and immunohistochemically compared.

RESULTS

PGA (7 cases) was characterized by i) a well-demarcated, polypoid lesion and ii) packed tubular components resembling pyloric glands. gICPNs (14 cases) were subdivided into i) pyloric gland predominant (2 cases), ii) foveola predominant (6 cases) and iii) mixed foveola and pyloric gland type (6 cases). gICPNs were also divided into a solitary, polypoid lesion with well demarcation from the surrounding mucosa (5 cases) and a conglomerated polypoid and granular lesions with poor demarcation (9 cases). PGA shared gross and histologic features with solitary, polypoid gICPNs, and PGA could be regarded as solitary gICPN predominantly composed of pyloric glands. Nuclear expression of β-catenin was found in 6 of 7 PGA, but absent in gICPN, including solitary, polypoid gICPN.

CONCLUSION

PGA could correspond to a solitary gICPN mainly composed of pyloric glands, but may undergo a different molecular pathway from gICPN.

Polypoid invasive carcinoma of the gallbladder-Another challenging polypoid neoplasm

BACKGROUND

Invasive gallbladder carcinoma generally presents as nodular-sclerosing growth. Recently, "polypoid invasive carcinoma (PICA)" showing grossly visible polypoid neoplasm and histologically invasive carcinoma with no adenomatous components was proposed as a neoplastic polyp of the gallbladder.

METHODS

We herein report five cases of PICA collected from 49 cases of invasive gallbladder carcinoma in comparison with another polypoid preinvasive neoplasm of gallbladder, intracholecystic papillary neoplasm (ICPN).

RESULTS

Polypoid invasive carcinomas were composed of four males and one female with an average age of 74 years. Polypoid lesions were sessile (height ranging from 6 to 10 mm and the largest diameter ranging from 12 to 40 mm), and histologically, polypoid neoplasms presented papillary configuration containing tubular and cribriform components with thin inflammatory, fibrotic stroma. Polypoid carcinoma invaded directly and continuously into the gallbladder wall with destruction of the muscle layer. These patterns of PICA were different from ICPN, showing papillary patterns containing tubular components with fine fibrovascular stalks and with occasional focal stromal invasion but with preserved muscle layer. Post-operative outcome was not favorable in PICA but was favorable in ICPN.

CONCLUSIONS

Polypoid invasive carcinoma shared several pathological features with ICPN, such as intraluminal polypoid pattern with papillary configurations, but PICAs were invasive adenocarcinoma with destruction of muscle layer while ICPNs were preinvasive neoplasm with occasional focal stromal invasion, thus both should be differentiated from each other.

Histopathological evidence of intrahepatic cholangiocarcinoma occurring in ductal plate malformation: A clinicopathologic study of 5 cases

Ductal plate malformations (DPM) arise from abnormal remodeling of the embryologic ductal plate of the liver. Malignant transformation of DPMs to intrahepatic cholangiocarcinoma (iCCA) has been reported in very rare instances but is viewed with some skepticism. We report the clinicopathological findings in five cases of iCCA, occurring in liver with DPM-like features. All tumors were less than 5 cm, often presented as stage T1a tumors. Histologically, a typical tumor showed a vague multinodular architecture with larger, irregular, tortuous glandular structures with microcystic dilation, intraluminal fibroepithelial projection, and bridge/island formation. The tumor cells were relatively small, bland, and without obvious pleomorphism. Interestingly, DPM presented as a histopathological transition sequence of definitively benign to biliary intraepithelial neoplasia (bilIN), then finally to iCCA. A complete pushing border, with entrapped portal tracts at the edge of the main tumor, suggested a replacing growth pattern. There was gradually increased expression of Ki-67 and p53 in these transition phases from benign to bilIN then to iCCA with DPM-like features. The neoplastic epithelium exhibited immunoreactivity in EpCAM, MUC1, NCAM, and CK19. KRAS mutation was found in 2 of the 5 iCCA cases with DPM-like features. Multifocal DPMs or VMCs with bilIN were dispersed in the non-tumor liver parenchyma in 3 of the 5 cases. The neoplasm was interpreted as iCCA arising in DPM, which may have originated from small bile duct or hepatic precursor cells. More studies are needed to verify this scarce entity and its premalignant properties.

Characterization of high-grade biliary intraepithelial neoplasm of the gallbladder in comparison with intracholecystic papillary neoplasm

Biliary intraepithelial neoplasm (BilIN) is characterized by a microscopically identifiable preinvasive neoplasm of the biliary tract. In this study, the high-grade BilIN of gallbladder was examined pathologically and compared with the intracholecystic papillary neoplasm (ICPN) of gallbladder. Sixteen high-grade BilINs (height <0.5 cm) collected from 2297 cholecystectomies (0.7%) and another three cases (19 cases total) were examined and compared with 34 cases of ICPN (greatest diameter ≥1 cm and height ≥0.5 cm). High-grade BilINs were incidentally found in 11 cholecystectomies, and the remaining eight were cholecystectomized in cases with a preoperative diagnosis of carcinoma. The largest diameter ranged from 0.5 to 6 cm. While 13 cases were recognized grossly as clustered granular and rough mucosa, the remaining were almost unrecognizable. Histologically, the high-grade BilINs showed intraepithelial neoplastic growth. Furthermore, they frequently showed intraepithelial replacement growth to non-neoplastic glands and cystic lesions in the gallbladder. The lesions presented with flat, wave or fold-like patterns, including tubular components. Short papillary components were also found in 13 cases. Gastric and biliary subtypes were frequent. Several foci of stromal invasion were found in the short papillary components in three cases. The lower polypoid or granular parts of conglomerated ICPNs showed intraepithelial neoplastic lesions sharing many features with high-grade BilINs with short papillary components. In conclusion, high-grade BilINs showed intraepithelial growth of neoplastic epithelia involving the mucosa. A morphologic continuum was noted between high-grade BilINs with short papillary components and conglomerated ICPNs, suggesting that conglomerated ICPNs may arise from high-grade BilINs with short papillary components.