Hepatic Mucinous Cystic Neoplasms Research Articles

To identify important MRI features to differentiate hepatic mucinous cystic neoplasms from septated hepatic cysts based on random forest.

To identify important MRI features to differentiate hepatic mucinous cystic neoplasms (MCN) from septated hepatic cysts (HC) using random forest andcompared with logistic regression algorithm. Pathologically diagnosed hepatic cysts and hepatic MCNs with pre-operative contrast-enhanced MRI in our hospital from 2010 to 2023 were collected and only septated lesions on enhanced MRI were enrolled. A total of 21 septated HC and 18 MCNs were included in this study. Eighteen MRI features were analyzed and top important features were identified based on random forest (RF) algorithm. The results were evaluated by the prediction performance of a RF model combining the important features and compared with the performance of the logistic regression (LR) algorithm. Finally, for each identified feature, diagnostic probability, sensitivity, and specificity were calculated and compared. Four variables, i.e., the septation arising from wall without indentation, multiseptate, intracapsular cyst sign, and solitary lesion were extracted as top important features with significance for MCNs by the random forest algorithm. The RF model using these variables had an AUC of 0.982 (0.95CI, 0.950-1.000), compared with the LR model based on two identified features with AUC of 0.931 (0.95CI, 0.846-1.000), p = 0.202. Among the four important features, multiseptate had the highest specificity (95.2%) and good sensitivity (72.2%, lower than the septation from wall without indentation, 94.4%) to diagnose MCNs. Four out of 18 MRI features were extracted as reliably important factors to differ hepatic MCNs from septated HC. The combination of these four features in a RF model could achieve satisfactory diagnostic efficacy.

Clonorchis sinensis: a mimic of hepatic mucinous cystic neoplasm or just a fluke?

Liver flukes, endemic in East Asia, are parasites that can infect humans and cause liver and bile duct disease. While most infected individuals are asymptomatic, chronic infection can lead to structural hepatobiliary manifestations including hepatomegaly, intrahepatic bile duct dilatation, epithelial hyperplasia, periductal fibrosis, and potentially cholangiocarcinoma. There are no reports of human cases of liver fluke infection presenting as a hepatic cystic lesion. We present the case of a 52-year-old asymptomatic Chinese immigrant presenting with a suspected mucinous cystic neoplasm of the liver. CT and Ultrasound examinations demonstrated an enlarging complex cyst involving segments II and III. Liver function tests, hydatid serology and tumour markers were normal. He underwent elective laparoscopic left hemi-hepatectomy with liver fluke discovered on histology. Subsequent genetic testing confirmed Clonorchis sinensis infection. The patient made an uneventful recovery from surgery and was treated with anthelminthic therapy. This case highlights the importance of considering liver fluke as a differential diagnosis for hepatic cystic lesions in patients from endemic regions. Appropriate diagnosis could avoid surgery, whilst targeted anthelminthic therapy minimises the risk of chronic infection and associated complications, including cholangiocarcinoma.

Atypical Image Change of Hepatic Mucinous Cystic Neoplasm.

Atypical Image Change of Hepatic Mucinous Cystic Neoplasm.

External validation of a machine learning based algorithm to differentiate hepatic mucinous cystic neoplasms from benign hepatic cysts.

To externally validate an algorithm for non-invasive differentiation of hepatic mucinous cystic neoplasms (MCN) from benign hepatic cysts (BHC), which differ in management. Patients with cystic liver lesions pathologically confirmed as MCN or BHC between January 2005 and March 2022 from multiple institutions were retrospectively included. Five readers (2 radiologists, 3 non-radiologist physicians) independently reviewed contrast-enhanced CT or MRI examinations before tissue sampling and applied the 3-feature classification algorithm described by Hardie et al. to differentiate between MCN and BHC, which had a reported accuracy of 93.5%. The classification was then compared to the pathology results. Interreader agreement between readers across different levels of experience was evaluated with Fleiss' Kappa. The final cohort included 159 patients, median age of 62years (IQR [52.0, 70.0]), 66.7% female (106). Of all patients, 89.3% (142) had BHC, and the remaining 10.7% (17) had MCN on pathology. Agreement for class designation between the radiologists was almost perfect (Fleiss' Kappa 0.840, p < 0.001). The algorithm had an accuracy of 98.1% (95% CI [94.6%, 99.6%]), a positive predictive value of 100.0% (95% CI [76.8%, 100.0%]), a negative predictive value of 97.9% (95% CI [94.1%, 99.6%]), and an area under the receiver operator characteristic curve (AUC) of 0.911 (95% CI [0.818, 1.000]). The evaluated algorithm showed similarly high diagnostic accuracy in our external, multi-institutional validation cohort. This 3-feature algorithm is easily and rapidly applied and its features are reproducible among radiologists, showing promise as a clinical decision support tool.

Differentiating hepatic mucinous cystic neoplasms from hydatid cyst of the liver

Differentiating hepatic mucinous cystic neoplasms from hydatid cyst of the liver

Hepatic Mucinous Cystic Neoplasm with Fistulation to The Duodenum: A Rare Case of Recurrent Cholangitis

Hepatic Mucinous Cystic Neoplasm with Fistulation to The Duodenum: A Rare Case of Recurrent Cholangitis

Multi-Center Follow-up Study to Develop a Classification System Which Differentiates Mucinous Cystic Neoplasm of the Liver and Benign Hepatic Cyst Using Machine Learning

To date, no clinically useful classification system has been developed for reliably differentiating mucinous cystic neoplasm (MCN) from a benign hepatic cyst (BHC) in the liver. The objective was touse machine learning and a multi-center study design to develop and assess the performance of a novel classification system for predicting whether a hepatic cystic lesion represents MCN or BHC. A multi-center cohort study identified 154 surgically resected hepatic cystic lesions in 154 subjects which were pathologic confirmed as MCN (43) or BHC (111). Readers at each institution recorded seven pre-determined imaging features previously identified as potential differentiating features from prior publications. The contribution of each of these features to differentiating MCN from BHC was assessed by machine learning to develop an optimal classification system. Although several of the assessed imaging features demonstrated statistical significance, only 3 imaging features were found by machine learning to significantly contribute to a potential classification system: (1) solid enhancing nodule (2) all septations arising from an external macro-lobulation (3) whether the lesion was solitary or one of multiple cystic liver lesions. The optimal classification system had only four categories and correctly identified 144/154 lesion (93.5%). This multi-center follow-up study was able to use machine learning to develop a highly accurate classification system for differentiation of hepatic MCN from BHC, which could be readily applied to clinical practice.

Hepatic Mucinous Cystic Neoplasm Deceptive as Hydatid Cyst: Message Learned

Purpose: Mucinous cystic neoplasms (MCN) are infrequent non-invasive lesion of the liver. The diagnosis of such lesions relies mainly on the histopathological findings. They are often misinterpreted as hydatid cysts clinically and on imaging leading to partial resection or deroofing. Case presentation: Case 1: A 32-year-lady presented with upper abdominal pain and on evaluation found to have well-defined cystic lesion with smooth wall and thin septae in segment III/IV of liver. Robotic deroofing of cyst wall was performed. Microscopic examination revealed it to be mucinous cystadenoma. In view of histopathology and raised fluid CEA and CA 19-9 levels, she was re-operated for complete excision of cystadenoma. Subsequent, histopathology reported mucinous cystadenoma with clear margins. Case 2: A 57-year-lady presented with complaint of awareness of lump in right hypochondrium. On evaluation, a large unilocular cystic mass lesion was noted in the segment IV/V of liver. Intraoperatively, ∼1 liter of cyst fluid was drained with de-roofing of cyst wall was performed. Her histopathology was suggestive of MCN of the liver with no features of high-grade dysplasia or malignancy. She was contacted but lost to follow up. However, after 2 years she again reported with complaints of pain in upper abdomen. CECT abdomen revealed a recurrent multilocuated cystic lesion in the remaining segment IVb of the liver. She was counselled and re-resection of residual lesion with gall bladder was performed. Histopathology examination again confirmed MCN. Now, both the patients are doing well after 1 year of re-do surgery and having no features of recurrence. Conclusion: MCN-L are rare with a wide clinical with radiological presentation and may be misdiagnosed pre-operatively. Complete excision, even if re-do surgery has to be done as it prevents future recurrence and malignant conversion.

Hepatic Mucinous Cystic Neoplasm Versus Simple Biliary Cyst: Assessment of Distinguishing Imaging Features Using CT and MRI.

OBJECTIVE. The purpose of our study was to identify the imaging features that differentiate a hepatic mucinous cystic neoplasm (MCN) from a simple biliary cyst. MATERIALS AND METHODS. Surgically resected hepatic MCNs and simple biliary cysts over a 20-year period (October 29, 1997-January 23, 2018) with preoperative CT, MRI, or both were retrospectively identified. Included cases underwent histopathologic confirmation of diagnosis based on the 2010 World Health Organization criteria and blinded imaging review. Various imaging features, including cyst shape and septal enhancement, were assessed for performance. For septate cysts, the relationship of the septation to the cyst wall-that is, arising from the wall without an indentation versus arising from an external macrolobulation-was recorded. Statistical analysis was performed for the imaging features with the chi-square test. RESULTS. The study group comprised 22 hepatic MCNs and 56 simple biliary cysts. A unilocular hepatic cystic lesion was highly predictive of a simple biliary cyst (positive predictive value = 95.2%). The imaging feature of septations arising only from macro-lobulations was 100% specific for a simple biliary cyst on CT (p = 0.001). The presence of septations arising from the cyst wall without indentation was 100% sensitive for hepatic MCN but was only 56.3% specific on CT. Septal enhancement reached 100% sensitivity for hepatic MCN on MRI (p = 0.018). CONCLUSION. The presence of septations, relationship of the septations to the cyst wall, and septal enhancement were sensitive imaging features in the detection of hepatic MCN. The imaging feature of septations arising only from macrolobulations in the cyst wall was specific for simple biliary cysts on CT and helped differentiate simple biliary cysts from hepatic MCNs.

Steroidogenesis in ovarian-like mesenchymal stroma of hepatic and pancreatic mucinous cystic neoplasms.

Aim Mucinous cystic neoplasms (MCNs) occur in the ovary, pancreas, and retroperitoneum but very rarely in the liver. Mucinous cystic neoplasms are known to harbor ovarian-like mesenchymal stroma (OLS) expressing progesterone and estrogen receptors. In this study we evaluated steroidogenesis in OLS of 25 hepatic MCNs and 24 pancreatic MCNs. Methods Both steroid receptors and steroidogenic factors were immunohistochemically evaluated using H-scores and results were compared with those in 15 ovarian MCNs and 10 normal ovaries. Results Androgen receptor (AR) H-scores in OLS were significantly higher in hepatic, pancreatic, and ovarian MCN than those in normal ovaries. H-scores of cytochrome P450 17α-hydroxylase/c17-20 lyase (P450c17) and 5α-reductase-1 (5αRED-1) in the stroma were significantly higher in OLS of hepatic and pancreatic MCN than in the stroma of ovarian MCN and normal ovary. In tumor epithelium, AR H-scores were significantly higher in hepatic and pancreatic MCN than in ovarian MCN. In both hepatic and pancreatic MCN, a significant positive correlation was detected between AR H-score in the epithelium and P450c17 H-score in OLS (hepatic MCN: Pearson's r = 0.446, P = 0.025; pancreatic MCN: r = 0.432, P = 0.035). In pancreatic MCN, a significantly positive correlation was detected between AR H-score in the tumor epithelium and 5αRED-1 H-score in OLS (Pearson's r = 0.458, P = 0.024). Conclusions These results indicated that locally produced androgens in OLS could be pivotal for tumorigenesis of both hepatic and pancreatic MCN and influence epithelial cells, possibly in a paracrine fashion, which could represent biological significance of OLS in these neoplasms.

Insights in laparoscopic surgery of mucinous cystic neoplasm of the liver

The case report (with video) by Smerieri et al . (1) of Surgical Endoscopy , concerning the laparoscopic surgical treatment of a hepatic mucinous cystic neoplasm (MCN-H), it lends itself to numerous interesting reflections.

Differentiating Simple Hepatic Cysts from Mucinous Cystic Neoplasms: Radiological Features, Cyst Fluid Tumour Marker Analysis and Multidisciplinary Team Outcomes

Background: Differentiating hepatic mucinous cystic neoplasms (MCNs) from simple hepatic cysts (SCs) preoperatively is a challenging task. Our aim was to determine whether radiological features on ultrasound scan (USS), CT or MRI, cyst fluid tumour markers, or multidisciplinary team (MDT) outcomes could differentiate MCN from SC. Methods: A retrospective review of radiological features, cyst fluid tumour marker levels and MDT outcomes in 52 patients was performed. Results: There were 13 patients with MCN, 38 with SC and one ciliated foregut cyst. MCNs were more often solitary (p = 0.006). Although no other individual radiological characteristic on USS, CT or MRI was predictive of MCN, MDT outcomes stating that a cyst was complex in nature were highly predictive (p = 0.0007). Cyst fluid carbohydrate antigen 19-9, carcino-embryonic antigen and cancer antigen 125 were unable to differentiate MCN from SC (p = 0.45, p = 0.49, and p = 0.73, respectively). Conclusions: MDT outcomes are of greatest value when trying to differentiate MCN from SC, as well as having a solitary cyst on imaging. Conventional cyst fluid tumour markers are unhelpful. All suspicious cystic liver lesions should be discussed pre-operatively by a hepatobiliary MDT to determine the most appropriate surgical approach.

"Biliary Diseases with Pancreatic Counterparts": Cross-sectional Imaging Findings.

On the basis of the similarities in the histopathologic findings and the clinical-biologic behaviors of select biliary and pancreatic conditions, a new disease concept, "biliary diseases with pancreatic counterparts," has been proposed. Both nonneoplastic and neoplastic pathologic conditions of the biliary tract have their counterparts in the pancreas. Immunoglobulin G4 (IgG4)-related sclerosing cholangitis is the biliary manifestation of IgG4-related sclerosing disease, and type 1 autoimmune pancreatitis is its pancreatic counterpart. People with chronic alcoholism can develop peribiliary cysts and fibrosis as well as pancreatic fibrosis and chronic pancreatitis simultaneously. Pancreatic ductal adenocarcinoma, intraductal papillary mucinous neoplasm, and mucinous cystic neoplasm are considered pancreatic counterparts for the biliary neoplasms of extrahepatic cholangiocarcinoma, intraductal papillary neoplasm of the biliary tract, and hepatic mucinous cystic neoplasm, respectively. The anatomic proximity of the biliary tract and the pancreas, the nearly simultaneous development of both organs from the endoderm of the foregut, and the presence of pancreatic exocrine acini within the peribiliary glands surrounding the extrahepatic bile ducts are suggested as causative factors for these similarities. Interestingly, these diseases show "nearly" identical findings at cross-sectional imaging, an observation that further supports this new disease concept. New information obtained with regard to biliary diseases can be used for evaluation of pancreatic abnormalities, and vice versa. In addition, combined genetic and molecular studies may be performed to develop novel therapeutic targets. For both biliary and pancreatic diseases, imaging plays a pivotal role in initial diagnosis, evaluation of treatment response, efficacy testing of novel drugs, and long-term surveillance.

Distinction between intraductal papillary neoplasms and hepatic mucinous cystic neoplasms

Objective To compare the clinicopathologic features of biliary intraductal papillary neoplasm (bIPN) and mucinous cystic neoplasms (MCN).Methods The clinical,pathological and prognostic data of 22 patients with bIPN and 14 patients with MCN who underwent surgical treatment from January 1998 to July 2013 were retrospectively analyzed and compared.Results Patients with bIPN were significantly older than patients with MCN (59.7 ± 10.8 vs 44.9 ±9.6,P ＜0.001).Tumors of the bIPN patients were much smaller than those of the MCN patients [(5.5 ± 3.3) cm vs (11.7 ± 5.4) cm,P =0.009].The main symptoms of both bIPN and MCN patients were abdominal pain (31.8％ vs 35.7％,P =0.809),but bIPN patients were more commonly associated with hepatolithiasis (40.9％ vs 0,P =0.006).The location of the mass differed,with bIPN usually occurring in the left lobe,whereas MCN in the right lobe (P =0.028).Luminal communication between cystic tumors and bile ducts was detected in all surgically resected bIPN,which was significantly different from the MCN (100％ vs 0％ ; P ＜ 0.001).Malignant lesions were more common in bIPN patients than in MCN patients (81.8％ vs 42.9％ ; P =0.029).The overall 5-year survival rates of patients with bIPN and MCN were 85.3％ and 100％ respectively (P =0.097).Conclusions bIPN represents a distinct clinicopathologic entity that differs clinically and histologically from MCN.Curative resection has a favorable prognosis for patients with bIPN or MCN. Key words: Liver; Bile duct; Papillary neoplasms ; Cystic neoplasms; Diagnosis differential

Intraductal Papillary Neoplasm of the Bile Duct Arising From a Background of Autoimmune Hepatitis: A Case Report

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare cystic tumor of the liver defined separately from hepatic mucinous cystic neoplasm. Development of liver cancer in patients with autoimmune hepatitis (AIH) is also sporadic, and such cases reported previously have been hepatocellular carcinoma. Here we report a 50-year-old man with IPNB complicated by AIH who underwent a successful extended left hepatectomy. Histopathology and immunohistochemical staining of the resected tumor revealed that it was a pancreatobiliary-type IPNB expressing both MUC5AC and MUC6, accompanied by carcinoma in situ expressing p53, Ki-67 and CA19-9. The histopathology of the background liver was compatible with that of AIH showing interface hepatitis with accompanying plasma cell infiltration. The patient has remained free of cancer recurrence for 12 years following the hepatectomy, and liver dysfunction caused by AIH has been controllable by steroid administration. This is the first report of pancreatobiliary-type IPNB associated with AIH. doi: http://dx.doi.org/10.4021/jmc1439w

Intraductal Papillary Neoplasm of the Bile Duct Arising From a Background of Autoimmune Hepatitis: A Case Report

Intraductal papillary neoplasm of the bile duct (IPNB) is a rare cystic tumor of the liver defined separately from hepatic mucinous cystic neoplasm. Development of liver cancer in patients with autoimmune hepatitis (AIH) is also sporadic, and such cases reported previously have been hepatocellular carcinoma. Here we report a 50-year-old man with IPNB complicated by AIH who underwent a successful extended left hepatectomy. Histopathology and immunohistochemical staining of the resected tumor revealed that it was a pancreatobiliary-type IPNB expressing both MUC5AC and MUC6, accompanied by carcinoma in situ expressing p53, Ki-67 and CA19-9. The histopathology of the background liver was compatible with that of AIH showing interface hepatitis with accompanying plasma cell infiltration. The patient has remained free of cancer recurrence for 12 years following the hepatectomy, and liver dysfunction caused by AIH has been controllable by steroid administration. This is the first report of pancreatobiliary-type IPNB associated with AIH. J Med Cases. 2013;4(10):654-659 doi: http://dx.doi.org/10.4021/jmc1439w

Immunohistochemical characteristics and malignant progression of hepatic cystic neoplasms in comparison with pancreatic counterparts

The recent World Health Organization classification for tumors of the digestive system defined grossly and histologically hepatic mucinous cystic neoplasms and intraductal papillary neoplasms of the bile duct separately. In this study, the immunohistochemical features of intraductal papillary neoplasm of the bile duct (19 cases) and hepatic mucinous cystic neoplasm (5 cases) were characterized and compared with those of similar pancreatic lesions, intraductal papillary mucinous neoplasm of the pancreas (12 cases), and pancreatic mucinous cystic neoplasm (6 cases) and with those of other biliary cystic lesions, peribiliary cysts (10 cases). Intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas frequently expressed cytokeratin 7; mucin core proteins 1, 2, 5AC, and 6; trypsin; and amylase. Hepatic and pancreatic mucinous cystic neoplasms frequently expressed cytokeratin 7, mucin core proteins 1 and 5AC, estrogen receptor, progesterone receptor, trypsin, and amylase. Estrogen and progesterone receptors were expressed in the subepithelial stromal cells. The groups with intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas were different from the groups with hepatic and pancreatic mucinous cystic neoplasm with respect to several phenotypes reflecting gastric and intestinal metaplasia and also the lack of expression of estrogen and progesterone receptors. The Ki-67 and p53 labeling indexes increased significantly with the malignant progression of intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas. The p16 labeling index decreased and EZH2 labeling index increased significantly with the malignant progression of intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas. In conclusion, intraductal papillary neoplasm of the bile duct and hepatic mucinous cystic neoplasm might be regarded as biliary counterparts of intraductal papillary mucinous neoplasm of the pancreas and pancreatic mucinous cystic neoplasm, respectively, and the mucinous cystic neoplasm and intraductal papillary neoplasm groups differed from each other. Labeling indexes of Ki-67, p53, p16, and EZH2 were comparable in intraductal papillary neoplasm of the bile duct and intraductal papillary mucinous neoplasm of the pancreas along with their malignant progression, suggesting a common carcinogenic process of the tumors.

Giant mucinous cystic neoplasms of pancreas and liver with unusual adipose tissue component: a case report.

Simultaneous occurrence of pancreatic and hepatic mucinous cystic neoplasms is very rarely reported in the literature. We present a case with extensive fatty component of the pancreatic tumour arising from the head of the pancreas and attaining a huge size before being treated by Whipple's pancreatoduodenectomy and subsequently by a right hepatectomy for the hepatic tumour.

Mucinous cystic neoplasms of the liver: a clinicopathological study and comparison with intraductal papillary neoplasms of the bile duct

Mucinous cystic neoplasm of the liver has been a controversial entity, in particular, regarding differentiation from intraductal papillary neoplasm of the bile duct. In this study, we compared the characteristics of hepatic mucinous cystic neoplasms with ovarian-like stroma (n=29) to those of cyst-forming intraductal papillary neoplasms of the bile duct (n=12). Radiological or macroscopic appearance, histological grade of malignancy, and postoperative clinical course were recorded. Immunohistochemistry for biliary or gastrointestinal markers was performed to characterize cell phenotypes. The patients with hepatic mucinous cystic neoplasm were all female and ranged in age from 21 to 67 years, which was significantly younger than that in the patients with biliary intraductal papillary neoplasm. Eighteen mucinous cystic neoplasms (76%) were located in the left lobe, with 13 (54%) in segment IV. Mucinous cystic neoplasms were significantly larger than intraductal papillary neoplasms (median diameter: 110 vs 50 mm, P=0.008). In contrast to intraductal papillary neoplasms that were all histologically malignant, 26 mucinous cystic neoplasms (90%) were adenomas, 2 (7%) were borderline malignant, and 1 (3%) was a carcinoma in situ. Benign mucinous cystadenomas had the pure biliary immunophenotype, whereas gastrointestinal markers including cytokeratin 20 and mucin core proteins 2, 5AC, and 6 were more frequently expressed in borderline or malignant mucinous cystic neoplasms and biliary intraductal papillary neoplasms. There was no mortality in the patients with mucinous cystic neoplasm, whereas one patient with intraductal papillary neoplasm died of cancer. In conclusion, hepatic mucinous cystic neoplasms and biliary intraductal papillary neoplasms have different clinicopathological characteristics as evidenced by differences in the age and gender of patients, macroscopic appearance, immunophenotypes, and grades of malignancy.

A Comparison of Hepatic Mucinous Cystic Neoplasms With Biliary Intraductal Papillary Neoplasms

There is controversy regarding the term biliary intraductal papillary neoplasms (IPN-B) and their pathology, which frequently are confused with hepatic mucinous cystic neoplasms (MCN). We aimed to summarize the clinicopathologic features of IPN-B and differentiate them from MCN. From January 1998 to December 2007, there were 19 patients with intrahepatic IPN-B and 13 patients with MCN who underwent surgical treatment at Zhongshan Hospital. Multiple demographic and clinicopathologic parameters were reviewed retrospectively and compared between the groups. The mean ages of patients with IPN-B and MCN were 59.5 +/- 11.1 and 44.4 +/- 9.7 years, respectively (P = .0004); the male:female ratios also differed (11:8 vs 2:11; P = .028). Tumors were significantly smaller (6.0 vs 11.2 cm; P = .006) in patients with IPN-B than in those with MCN. More patients with IPN-B also had hepatolithiasis (47.4% vs 0%, P = .004); cholangiectasis and communication between the cyst and main bile duct were more frequent in patients with IPN-B than in those with MCN (P < .001). The IPN-B consisted of 4 subtypes--the gastric subtype was the least invasive. Malignant lesions were more common in patients with IPN-B than in those with MCN (78.9% vs 38.5%; P = .03). The overall 5-year survival rates of patients with IPN-B and MCN were 82% and 100%, respectively. Intrahepatic IPN-B represents a distinct clinicopathologic entity that differs clinically, histologically, and radiologically from MCN. Curative resection has a favorable prognosis for patients with IPN-B, but further studies of its subtype are required.