Stent Graft Placement for Injured Visceral Artery.

Injury of the visceral artery is a potentially fatal complication of iatrogenic procedures, trauma, and tumors. A stent graft can achieve rapid exclusion of the injured arterial portion and minimize the risk of ischemic complications by preserving arterial flow to organs. Although various types of stent grafts are available worldwide, Viabahn has only been approved for visceral arterial injury in Japan. The reported technical and clinical success rates, including cases with injured pelvic or thoracic arterial branches, are 80%-100% and 66.7%-100%, respectively. Severe ischemic complications are rare; however, fatal ischemia occurs when the stent graft is immediately occluded. The necessity of antiplatelet therapy is controversial, and a target artery diameter ≤ 4 mm is a significantly higher risk factor of stent-graft occlusion.

Pathological survey of precursor lesions in cholangiocarcinoma.

BACKGROUND: To clarify the pathological significance of two precursors (high-grade biliary intraepithelial neoplasm [BilIN] and intraductal papillary neoplasm of bile duct [IPNB]) in cholangiocarcinomas (CCAs). METHODS: Ninety-one cases of CCA (47 distal CCAs [dCCAs], 31 perihilar CCAs [pCCAs] and 13 intrahepatic CCAs of large duct type [LD-iCCAs]) were examined for their association with precursors. Neoplastic intraepithelial lesions without underlying infiltrating carcinoma in the surrounding mucosa of CCAs were considered to reflect high-grade BilIN. High-grade BilIN and IPNB were subdivided into gastric, biliary, intestinal and oncocytic subtypes, while CCAs were subdivided into gastrobiliary, intestinal and oncocytic subtypes. The postoperative overall survival (OS) was examined. RESULTS: Fifty-four and 8 of 91 CCAs were associated with high-grade BilIN and IPNB, respectively, while these precursors were unidentifiable in the remaining CCAs. A majority of CCAs were of the gastrobiliary subtype, while the intestinal subtype was occasionally detected, and the oncocytic subtype was rare. CCAs with high-grade BilIN showed a similar postoperative OS to CCAs without precursors, while CCAs with IPNB showed a favorable postoperative OS compared to CCAs without precursors. CONCLUSIONS: CCAs were frequently associated with precursors; high-grade BilIN may be a major precursor and IPNB a minor one. CCAs with IPNB showed a favorable postoperative OS compared to CCAs with high-grade BilIN.

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.

Pathologic patterns of invasive carcinoma associated with intraductal papillary neoplasms of bile duct (IPNB).

The pathologic features of invasive carcinoma associated with IPNB remain to be clarified. By using 82 cases of IPNB, the pathologic spectrum of associated invasive carcinoma and its correlation with their post-operative overall survival (OS) were examined. Invasive carcinoma was found in 52 cases (63 %) of IPNB and was classifiable into three patterns (patterns A, B and C). Pattern A was characterized by microscopic foci of invasive carcinoma in the fibrovascular stalks or confined to the bile duct mucosa and wall beneath the intraluminal pre-invasive neoplastic components of IPNB (23 cases) and pattern B by invasive carcinoma in the periductal connective tissue and in the adjacent organ(s) mainly near or beneath the intraluminal component(s) of IPNB (15 cases). Pattern C showed nodular invasive carcinoma considerably involving the intraluminal pre-invasive components and the bile duct mucosa and wall adjacent to the intraluminal pre-invasive components of IPNB (14 cases). Recognition of these three patterns of invasive carcinoma associated with IPNB may expand the pathologic spectrum of IPNB. IPNBs without invasive carcinoma showed a favorable post-operative-OS compared with those with invasion as a whole and those of pattern B and C, respectively, but showed a similar post-operative-OS to that of pattern A. IPNB of pattern B and C showed an unfavorable post-operative outcome, though there was no difference between pattern B and C. Understanding of the pathologic spectrum of associated invasive carcinoma may facilitate further pathological analysis of IPNB.

Polypoid invasive carcinoma of bile duct: report of four cases.

Recently, "polypoid invasive carcinoma (PICA)" showing grossly visible polypoid, invasive carcinoma with no adenoma component was proposed as a neoplastic polyp of the gallbladder. Herein, we report four cases of PICA of the bile duct. PICA cases of bile duct showed single, sessile polypoid growth grossly, and polypoid components were composed of invasive carcinoma of papillary/tubular patterns with active desmoplasia, and invaded directly and continuously into the bile duct wall and periductal tissue. While PICA and other intraductal papillary neoplasm of bile duct (IPNB) shared several features, PICA showed an invasive carcinoma growing in the duct lumen and also invading into the bile duct wall, thus different from IPNB which is the intraluminal polypoid, preinvasive epithelial neoplasia with back-to-back epithelial units. Taken together, PICA and IPNB could be differentiated from each other.

Association of precursors with invasive adenocarcinoma of the gallbladder: A clinicopathological study.

BACKGROUND: The current WHO classification proposed high-grade biliary intraepithelial neoplasm (BilIN) and intracholecystic papillary neoplasm (ICPN) as precursors of the gallbladder carcinoma (GBC). Herein, conventional GBCs (cGBCs) were pathologically examined with respect to these two precursors. METHODS: Forty-seven cases of GBC with grossly visible invasions were collected from Fukui Saiseikai Hospital. The association of two precursors was analyzed referring to pathologic features of cGBCs and post-operative survival. RESULTS: 20 cGBCa (42.6%) were associated with either of two precursors in the surrounding mucosa: high-grade BilIN in 15 cases (31.9%) or ICPN in 5 cases (10.6%). Association of precursors was not related to gross types of and histological differentiation of cGBC. cGBCs without precursors showed frequent vascular/perineural invasion and lymph node metastasis, though cGBCs with and without precursors presented a similar post-operative survival. High-grade BilIN and ICPN associated with cGBCs showed more complicated cytoarchitectural features compared with those with no or focal invasion. CONCLUSION: More than 40% of cGBCs were associated with high-grade BilIN or ICPN, and the former was a frequent precursor. cGBCs without precursors showed aggressive pathologic features. Clinical detection of these precursors may make early treatment of cGBCs possible.

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.

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 ß-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.

Efficacy of Superselective Conventional Transarterial Chemoembolization Using Guidance Software for Hepatocellular Carcinoma within Three Lesions Smaller Than 3 cm.

The indication of transarterial chemoembolization (TACE) has advanced to hepatocellular carcinoma (HCC) of Barcelona Clinic Liver Cancer (BCLC) stage A when surgical resection (SR), thermal ablation, and bridging to transplantation are contraindicated; however, TACE for small HCC is frequently difficult and ineffective because of less hypervascularity and the presence of tumor portions receiving a dual blood supply. Here, we report outcomes of superselective conventional TACE (cTACE) for 259 patients with HCCs within three lesions smaller than 3 cm using guidance software. Automated tumor feeder detection (AFD) functionality was applied to identify tumor feeders on cone-beam computed tomography during hepatic arteriography (CBCTHA) data. When it failed, the feeder was identified by manual feeder detection functionality and/or selective angiography and CBCTHA. Regarding the technical success in 382 tumors (mean diameter, 17.2 ± 5.9 mm), 310 (81.2%) were completely embolized with a safety margin (5 mm wide for HCC ≤25 mm and 10 mm wide for HCC >25 mm). In 61 (16.0%), the entire tumor was embolized but the safety margin was not uniformly obtained. The entire tumor was not embolized in 11 (2.9%). Regarding the tumor response at 2-3 months after cTACE in 303 tumors excluding those treated with combined radiofrequency ablation (RFA) or SR and lost to follow-up, 287 (94.7%) were classified into complete response, seven (2.3%) into partial response, and nine (3.0%) into stable disease. The mean follow-up period was 44.9 ± 27.6 months (range, 1-109) and the cumulative local tumor progression rates at 1, 3, 5, and 7 years were 17.8, 27.8, 32.0, and 36.0%, respectively. The 1-, 3-, 5-, and 7-year overall and recurrence-free survival rates in 175 patients, excluding those with Child-Pugh C class, who died of other malignancies, or who underwent combined RFA or hepatic resection, were 97.1 and 68.7, 82.8 and 34.9, 64.8 and 20.2, and 45.3 and 17.3%, respectively. Our results indicate the efficacy of superselective cTACE using guidance software for HCC within three lesions smaller than 3 cm.

[A case of metastatic melanoma in the gallbladder].

Malignant melanoma is an aggressive tumor with a high potential for distant metastases. Autopsy studies have shown that gallbladder metastases are found in 15% of patients. However, metastatic melanoma of the gallbladder is rarely discovered in living patients. A 73-year-old man was reported. The patient underwent surgical removal of malignant melanoma on his back and lymphadenectomy of the axillary lymph nodes. In addition, the patient developed cutaneous metastases to the right axillary and the middle of the chest 1.5 years after the surgery. Consequently, nivolumab chemotherapy was started. A computed tomography (CT) scan showed a well-enhanced mass in the gallbladder 4 months after. Abdominal ultrasonography revealed a 13-mm hypoechoic heterogeneous mass in the gallbladder with a hyperechoic layer on the mass surface. Magnetic resonance imaging demonstrated that the gallbladder tumor showed high signal intensity on T1-weighted images, low signal intensity on T2-weighted images, and high signal intensity on diffusion-weighted images. Positron emission tomography-CT revealed the slight uptake of fluorodeoxyglucose at the tumor. Endoscopic ultrasonography showed a hypoechoic tumor infiltrating the submucosal layer. The patient underwent open cholecystectomy. Examination of the resected specimens revealed a black, nodular-type tumor in the gallbladder body. The histopathological diagnosis was malignant melanoma. It was judged as metastatic melanoma of the gallbladder.

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.

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

Intracholecystic papillary neoplasm (ICPN) is a recently proposed gallbladder neoplasm. Its prevalence and pathologies remain to be clarified. A total of 38 ICPN cases (28 ICPNs identified among 1904 cholecystectomies (1.5%) and in 100 surgically resected primary gallbladder neoplasms (28%) in Fukui Prefecture Saiseikai Hospital, Japan, and other 10 ICPNs) were examined pathologically and immunohistochemically. They were composed of 21 males and 17 females with a mean age of 75 years old, and presented intraluminal growth of papillary lesions with fine fibrovascular stalks. ICPNs were relatively frequent in the fundus (n = 11) and body (n = 9). Grossly, the conglomerated sessile type (n = 30) was more frequent than the isolated polypoid type (n = 8). All cases were classified as high-grade dysplasia, and they were further divided into 22 cases presenting irregular structures and 16 cases presenting regular structures. The former showed frequent complicated lesions and stromal invasion (54.5%) compared to the latter (12.5%). Twenty-four cases showed predominantly either of four subtypes (11 gastric, 7 intestinal, 4 biliary and 2 oncocytic subtype), while the remaining14 cases showed mixture of more than two subtypes. In conclusion, ICPN presented unique preinvasive neoplasm with characteristic histopathologies. Irregular histologies and complicated lesions of ICPN were related to stromal invasion.

Reappraisal of pathological features of intraductal papillary neoplasm of bile duct with respect to the type 1 and 2 subclassifications.

The pathological spectrum of intraductal papillary neoplasm of bile duct (IPNB) remains to be clarified. A total of 186 IPNBs were pathologically examined using the type 1 and 2 subclassifications proposed by Japanese and Korean biliary pathologists incorporating a two-tiered grading system (low-grade and high-grade dysplasia), with reference to four subtypes (intestinal [i], gastric [g], pancreatobiliary [pb], and concocytic [o] subtype). IPNBs were classifiable into type 1 composed of low-grade dysplasia and 'high-grade dysplasia with regular structures' (69 IPNBs), and type 2 of 'high grade dysplasia with irregular structures and complicated lesions' (117 IPNBs). Type 1 was more common in the intrahepatic bile duct (78%), whereas type 2 was frequently located in the extrahepatic bile duct (58%). Mucin hypersecretion was more common in type 1 (61%) than in type 2 (37%). IPNBs were classifiable into the four subtypes: 86 iPNBs, 40 gIPNBs, 31 pbIPNBs, and 29 oIPNBs. The four subtypes were histologically evaluable with reference to the type 1 and 2 subclassifications. iIPNB and pbIPNBs were frequently classified as type 2, whereas types 1 and 2 were observed at similar rates in gIPNB and oIPNB. Stromal invasion was almost absent in type 1, irrespective of subtype, but was found in 66 of 117 type 2 IPNBs (P < .01), and postoperative outcome was favorable in IPNBs without invasion compared with IPNBs with invasion (P < .05). The type 1 and 2 subclassifications with reference to the four subtypes may provide useful information for understanding IPNB.

Intraductal Papillary Neoplasm of Bile Duct: Updated Clinicopathological Characteristics and Molecular and Genetic Alterations.

Intraductal papillary neoplasm of the bile duct (IPNB), a pre-invasive neoplasm of the bile duct, is being established pathologically as a precursor lesion of invasive cholangiocarcinoma (CCA), and at the time of surgical resection, approximately half of IPNBs show stromal invasion (IPNB associated with invasive carcinoma). IPNB can involve any part of the biliary tree. IPNB shows grossly visible, exophytic growth in a dilated bile duct lumen, with histologically villous/papillary neoplastic epithelia with tubular components covering fine fibrovascular stalks. Interestingly, IPNB can be classified into four subtypes (intestinal, gastric, pancreatobiliary and oncocytic), similar to intraductal papillary mucinous neoplasm of the pancreas (IPMN). IPNBs are classified into low-grade and high-grade based on lining epithelial features. The new subclassification of IPNB into types 1 (low-grade dysplasia and high-grade dysplasia with regular architecture) and 2 (high-grade dysplasia with irregular architecture) proposed by the Japan-Korea pathologist group may be useful in the clinical field. The outcome of post-operative IPNBs is more favorable in type 1 than type 2. Recent genetic studies using next-generation sequencing have demonstrated the existence of several groups of mutations of genes: (i) IPNB showing mutations in KRAS, GNAS and RNF43 belonged to type 1, particularly the intestinal subtype, similar to the mutation patterns of IPMN; (ii) IPNB showing mutations in CTNNB1 and lacking mutations in KRAS, GNAS and RNF43 belonged to the pancreatobiliary subtype but differed from IPMN. IPNB showing mutation of TP53, SMAD4 and PIK3CA might reflect complicated and other features characterizing type 2. The recent recognition of IPNBs may facilitate further clinical and basic studies of CCA with respect to the pre-invasive and early invasive stages.

Adenocarcinoma arising from a heterotopic pancreas in the first portion of the duodenum: a case report.

BACKGROUND: Heterotopic pancreas (HP) is defined as pancreatic tissue in organs with no anatomical continuity with the orthotopic pancreas. Based on the number of cases reported in the literature between the year 2000 and 2020, HP is rarely found causing malignant transformation of the duodenum. We herein report a case of adenocarcinoma arising from the HP in the first portion of the duodenum. CASE PRESENTATION: A 77-year-old Japanese man presented to our hospital with epigastric pain. Despite having undergone laparoscopic surgery for early sigmoid colon cancer a month earlier, serum levels of tumor-specific antigens, such as CA19-9, were elevated. After undergoing a series of radiologic examinations, the first portion of the duodenum was found thickened. However, a biopsy of the lesion showed no malignancy. Four months later, follow-up computed tomography (CT) scans showed that the lesion was thicker and involved the gastroduodenal artery (GDA), suggesting tumor invasion. A new biopsy did not detect the malignancy. However, serum tumor-specific antigen levels increased, especially duke pancreatic monoclonal antigen type 2 (5287 U/mL), in the absence of tumor in the orthotopic pancreas. The follow-up CT imaging showed a malignant tumor in the first portion of the duodenum. Five months later, we performed a subtotal stomach-preserving pancreaticoduodenectomy (SSPPD) for duodenal or HP cancer in the first portion of the duodenum, finding a lesion from the pyloric bulbs to the first portion of the duodenum, which invaded the adjacent pancreas and GDA. The pathological examination of the specimens revealed adenocarcinoma arising from HP. Nine months after surgery, no recurrence was found by radiologic imaging or tumor-specific antigen laboratory testing. CONCLUSIONS: HP adenocarcinoma is rare and difficult to diagnose preoperatively due to its submucosal location. Therefore, a careful follow-up with blood testing and radiologic imaging, as well as diagnostic surgery, is recommended.

Gastric subtype of intraductal papillary neoplasm of the bile duct: The pathologic spectrum.

BACKGROUND AND AIMS: Intraductal papillary neoplasms of bile duct (IPNBs) remain a challenging entity to manage. METHODS: The pathologic spectrum of 34 gastric subtype of IPNB (gIPNB) cases was examined in consideration of the type 1 and 2 subclassification proposed by Japan-Korea consensus and compared with gastric subtype of pancreatic intraductal papillary mucinous neoplasm (gIPMN) (44 cases). RESULTS: Type 1 gIPNBs (17 cases) showed regular papillary foveola with variable tubular pyloric glands. Eight of the type 1 gIPNBs showed low-grade dysplasia. Type 2 cases (n = 17) showed complicated papillary and tubular structures and high-grade dysplastic foveola and pyloric glands. Foveolas were predominant in 15 cases, while pyloric glands were predominant in 10 cases, and considerable areas of foveolas and pyloric glands in the remaining: these three were found similarly in type 1 and 2 gIPNB. gIPMNs showed central foveola with a peripheral pyloric gland. Such a pattern was recognizable in type 1 but vague in type 2. Type 1 was frequently found in the intrahepatic bile ducts and showed abundant mucin, as in gIPMNs, while type 2 also occurred in the extrahepatic bile ducts and were pathologically more malignant. CONCLUSION: Type 1 lesions shared features of gIPMN, while type 2 lesions differed from gIPMN and were more pathologically malignant.

Intraoperative Bile Duct Disruption Treated Using Intrahepatic Biliary Ablation with Ethanol: A Report of Two Cases.

We report two cases of intraoperative bile duct disruption. In case 1, an isolated bile duct in the remnant of the anterosuperior liver segment after right hepatic lobectomy for cholangiocarcinoma caused bile leakage. In case 2, bile leakage continued from a disrupted accessory hepatic duct during pancreaticoduodenectomy for pancreatic carcinoma. In both patients, a mixture of ethanol and iodized oil at a 10:1 ratio was injected into the disrupted bile duct under balloon occlusion. In case 1, the mixture was injected through a balloon catheter under balloon occlusion overnight. No severe complications developed in either case. Bile leakage stopped postoperatively and did not recur until the patients' death from tumor progression 14 and 16 months after surgery, respectively.

The Pathologic and Genetic Characteristics of the Intestinal Subtype of Intraductal Papillary Neoplasms of the Bile Duct.

The present study aimed to identify the pathologic and genetic characteristics of intestinal subtype of intraductal papillary neoplasm of the bile duct (iIPNB) showing columnar cells with pseudostratified, cigar-shaped nuclei, and basophilic or amphophilic cytoplasm with the diffuse immunohistochemical expression of CK20 and/or CDX2. A total of 34 cases of iIPNB were pathologically examined according to their anatomic location (the bile duct) and were then compared with the intestinal subtype of intraductal papillary mucinous neoplasm (iIPMN) of the pancreas (n=22). Mutations of 26 somatic genes were examined in formalin-fixed paraffin-embedded tissue specimens from 21 cases of iIPNB using the TruSight Tumor 26 gene panel and next-generation sequencing. iIPNB cases were divided into intrahepatic (n=6) and extrahepatic (n=28) categories. Intrahepatic IPNBs showed a less-complicated villous-papillary pattern, while extrahepatic IPNBs showed a papillary pattern with tubular and/or villous components and predominant high-grade dysplasia with complicated architectures. MUC5AC was frequently and extensively expressed in intrahepatic iIPNBs and iIPMNs but not in extrahepatic iIPNBs. CD10 was frequently expressed in extrahepatic IPNBs but not in intrahepatic iIPNBs or iIPMN. Genetic mutations of TP53 and PIK3CA, which were infrequent or absent in iIPMNs, were frequently detected in extrahepatic iIPNBs, while KRAS and GNAS, which were commonly observed in iIPMNs, were frequently detected in intrahepatic iIPNBs. Intrahepatic iIPNBs showed villous-papillary growth with features reminiscent of iIPMNs, while extrahepatic iIPNBs showed papillary growth with tubular and/or villous components, complicated histology and variable differences from iIPMNs, suggesting differences in the tumorigenesis of iIPNBs along the biliary tree.

High-grade PanIN presenting with localised stricture of the main pancreatic duct: A clinicopathological and molecular study of 10 cases suggests a clue for the early detection of pancreatic cancer.

AIMS: This study aimed to identify the pathological features of high-grade PanIN that presents with imaging-detectable abnormalities. METHODS AND RESULTS: Ten cases of isolated, main-duct, high-grade PanIN as the primary clinical presentation were identified. All patients presented with stenosis of the main pancreatic duct, with two being associated with extensive upstream duct dilatation (>5 mm in diameter). Pancreatic juice cytology suggested adenocarcinoma in all seven cases examined. In resected specimens, high-grade PanIN was present chiefly in the main pancreatic duct, with longitudinal extension ranging between 3 and 40 mm in length (median = 18 mm). In four cases, in which hypoechoic or hypovascular masses were observed on imaging, radiopathology correlations suggested that they represented parenchymal atrophy and subsequent fibrosis around affected ducts, but not invasive malignancy. On immunohistochemistry, the loss of p16 expression was found in five (50%), p53 overexpression in two (20%) and loss of SMAD4 expression in none (0%). KRAS mutations were detected in nine cases, with two dominant clones being found in three by ultrasensitive droplet digital polymerase chain reaction, suggesting the genetic heterogeneity of dysplastic cells composing individual lesions. Mutant GNAS was also observed in one case. CONCLUSIONS: Isolated high-grade PanIN may present with pancreatic duct stenosis. Therefore, intensive investigations including pancreatic juice cytology will be required for patients with unexplained pancreatic duct stenosis. The abnormal expression of p53 and SMAD4 is infrequent, while GNAS may be mutated in premalignant lesions mainly affecting the main pancreatic duct, similar to KRAS.

Ruptured pancreaticoduodenal artery aneurysm associated with median arcuate ligament compression and aortic dissection successfully treated with embolotherapy.

A 51-year-old man with a ruptured pancreaticoduodenal artery (PDA) aneurysm caused by compression of the celiac artery by the median arcuate ligament and aortic dissection involving the celiac axis was transferred to our hospital for endovascular treatment. A 4-F catheter was advanced into the superior mesenteric artery through the narrow true lumen via the left brachial artery, and coil embolization of the aneurysm was successfully performed. In this case, rapid increase of blood flow in the superior mesenteric artery, which compensated for the decreased celiac blood flow by aortic dissection, increased hemodynamic stress on the PDA, leading to aneurysmal rupture.