True diagnostic ability of EUS-guided fine-needle aspiration/biopsy sampling for small pancreatic lesions ≤10 mm and salvage diagnosis by pancreatic juice cytology: a multicenter study.

BACKGROUND AND AIMS: The diagnostic performance of EUS-guided fine-needle aspiration/biopsy sampling (EUS-FNAB) for pancreatic ductal adenocarcinoma (PDAC) ≤10 mm in diameter is relatively low. Pancreatic juice cytology (PJC) has gained attention because of its high sensitivity for small PDACs. We aimed to clarify the diagnostic ability of EUS-FNAB and the salvage ability of PJC for PDAC ≤10 mm. METHODS: Data obtained from attempted EUS-FNAB for patients with EUS-confirmed pancreatic tumors ≤10 mm (excluding pancreatic metastases/malignant lymphomas) were retrospectively analyzed. Patients who experienced technical failure or had a negative EUS-FNAB result and had a strong likelihood of PDAC based on imaging characteristics underwent PJC. PDAC was diagnosed using resected histologic specimens, EUS-FNAB-positive tumor growth on the imaging examination, or additional EUS-FNAB-positive results after increase in tumor size. The primary endpoint was the diagnostic ability of EUS-FNAB for PDAC ≤10 mm. The salvage ability of PJC was also assessed. RESULTS: Overall, 86 of 271 patients with pancreatic tumors ≤10 mm who underwent attempted EUS-FNAB were diagnosed with PDAC. The technical success rate, sensitivity, specificity, and accuracy of EUS-FNAB for PDAC ≤10 mm were 80.8%, 82.3%, 94.9%, and 91.3%, respectively. Among the 35 PDAC patients who experienced technical failure or false-negative results of EUS-FNAB, 26 (74.3%) were correctly diagnosed using salvage PJC. CONCLUSIONS: The true success rate and sensitivity of EUS-FNAB for PDAC ≤10 mm were relatively low. When EUS-FNAB for a pancreatic lesion ≤10 mm strongly suspected to be PDAC is unsuccessful or yields a negative result, PJC is recommended. (Clinical trial registration number: UMIN000049965.).

Pancreatic duct epithelial malignancy suggested by large focal pancreatic parenchymal atrophy in cystic diseases of the pancreas.

BACKGROUND: /Objectives: A cystic lesion is common in the pancreas. Focal pancreatic parenchymal atrophy (FPPA) has been reported as a sign of high-grade pancreatic intraepithelial neoplasia/carcinoma in situ (HGP/CIS). Some cystic lesions accompany FPPA. However, the relationship between a cystic lesion, FPPA, and the histopathological background of the pancreatic duct is unknown. METHODS: We retrospectively evaluated the data of 98 patients with a cystic lesion who underwent serial pancreatic juice aspiration cytologic examination (SPACE) because of accompanying FPPA, increased size of the cystic lesion, and pancreatic duct stricture at the base. RESULTS: The clinical diagnosis of a cystic lesion was intraductal papillary mucinous neoplasia (IPMN) and cysts in 72 (73.5%) and 26 (26.5%) patients, respectively. Ninety of the 98 patients (91.8%) had FPPA. Positive results (adenocarcinoma and suspicion) on SPACE were observed in 56 of all cases (57.1%), 48 of IPMN (66.7%), 8 of cysts (30.8%), and 54 of FPPA (59.3%), and were significantly associated with IPMN (p = 0.002) and the large FPPA (>269.79 mm2,p = 0.0001); moreover, these disorders are considerably related (p = 0.0003). Fifty patients (51.0%) with positive results on SPACE underwent surgery, with the histopathological diagnosis of epithelial malignancy in 42 patients (42.9%, 42/50, 84%). Many cystic lesions clinically diagnosed as IPMN were dilated branches covered by pancreatic intraepithelial neoplasia. CONCLUSIONS: Positive results on SPACE were significantly associated with the clinical diagnosis of IPMN and the large FPPA. Moreover, these disorders are significantly related. Surgery owing to positive results could lead to the histopathological diagnosis of HGP/CIS.

[Curative Resection after Chemotherapy for Advanced Extensive Cholangiocarcinoma-A Case Report].

A 73-year-old, male patient presented with the chief complaint of epigastric pain and received the diagnosis of extensive cholangiocarcinoma after a close examination. Extensive extension of the malignancy into the right and left hepatic ducts precluded a curative resection, and the patient received GC therapy. After 11 courses of GC over about 1 year, no new lesions or tumor progression was observed, and a bile duct mapping biopsy was performed to investigate the possibility of resection conversion. The results showed a marked decrease in atypia, and reactive atypia was diagnosed. A pancreaticoduodenectomy was performed, and histopathologically negative margins were obtained. The response to treatment was Grade Ⅱa according to the Evans classification. At 23 months after the start of treatment and 12 months after surgery, the patient is recurrence-free without adjuvant chemotherapy. Although the evidence for conversion surgery for biliary tract cancer has not been established, the long-term outcomes may be favorable.

[A Case of a Two-Stage Robotic-Assisted Surgery for a Neuroendocrine Tumor of the Pancreatic Tail with Simultaneous Single Liver Metastasis].

As medical insurance coverage for robotic surgery has been expanded in the field of gastrointestinal surgery in Japan, the number of cases undergoing robotic surgery for hepato-biliary-pancreatic disease has been increasing. Therefore, cases with malignant tumors and metastatic lesions tend to undergo robotic operation for both primary tumors and metastases. Herein, we report a case of neuroendocrine tumor(NET)in the pancreatic tail with simultaneous single liver metastasis, which was treated with two-stage robotic-assisted surgery. A 67-year-old female underwent a computed tomography scan and a hypovascularized tumor in the pancreatic tail region and liver was found. A biopsy of the pancreatic tumor by endoscopic ultrasound-guided fine needle aspiration demonstrated a NET G1-2. The liver lesion was diagnosed as a metastatic tumor, considering the other examinations. The patient underwent a robotic distal pancreatectomy(RDP)and was histopathologically diagnosed as NET G2. Sixty-three days after the RDP, a two-stage partial liver resection for the metastatic tumor was performed under robotic assistance. Curative resection was achieved through two-stage robot-assisted surgery, there were no postoperative complications.

Focal pancreatic parenchyma atrophy is a harbinger of pancreatic cancer and a clue to the intraductal spreading subtype.

BACKGROUND/OBJECTIVES: Radiological evidence of focal pancreatic parenchymal atrophy (FPPA) may presage early pancreatic ductal adenocarcinoma (PDAC) development. We aimed to clarify the incidence of FPPA and the clinicopathological features of PDAC with FPPA before diagnosis. METHODS: Data on endoscopic ultrasound-guided fine-needle biopsies and surgical samples from 170 patients with pancreatic cancer histologically diagnosed between 2014 and 2019 were extracted from the pathology database of Komagome Hospital and Juntendo University hospital and retrospectively evaluated together with 51 patients without PDAC. RESULTS: FPPA was identified in 47/170 (28%) patients before PDAC diagnosis and in 2/51 (4%) patients in the control group (P < 0.01). The median duration from FPPA detection to diagnosis was 35 (interquartile range [IQR]:16-63) months. In 24/47 (51%) patients with FPPA, the atrophic area resolved. The lesion was in the head and body/tail in 7/40 and 67/56 of the patients with (n = 47) and without FPPA (n = 123), respectively (P < 0.001). Histopathologically confirmed non-invasive lesions in the main pancreatic duct and a positive surgical margin in the resected specimens occurred in 53% vs. 21% (P = 0.078) and 29% vs. 3% (P = 0.001) of the groups, respectively. The PDAC patients with FPPA accompanied by a malignant pancreatic resection margin had high-grade pancreatic intraepithelial neoplasia. CONCLUSIONS: FPPA occurred in 28% of the PDAC group at 35 months prediagnosis. The FPPA area resolved before PDAC onset. Benchmarking previous images of the pancreas with the focus on FPPA may enable prediction of PDAC. PDAC with FPPA involves widespread high-grade pancreatic intraepithelial neoplasia requiring a wide surgical margin for surgical excision.

Gallbladder wall thickening in patients with IgG4-related diseases, with special emphasis on IgG4-related cholecystitis.

OBJECTIVES: Gallbladder (GB) wall thickening sometimes occurs in patients with autoimmune pancreatitis (AIP), a condition for which the name, IgG4-related cholecystitis, was proposed. We examined the radiological findings of the GB in patients with IgG4-related diseases and clinical features of patients with GB wall thickening and presented a hypothesis of its pathogenesis. MATERIALS AND METHODS: GB wall thickening was defined by thickness ≥ 4 mm. GB wall thickness was examined in 258 patients with IgG4-related disease. Clinical and imaging findings of 200 patients with AIP with and without GB wall thickening were then compared. RESULTS: GB wall thickening was detected in 58 patients (29%) with AIP and two patients with isolated IgG4-related sclerosing cholangitis. In the 60 GBs examined, wall thickening was diffuse, with the walls possessing a smooth inner surface. No GB wall thickening was detected among the 56 patients with IgG4-related disease without AIP or IgG4-related sclerosing cholangitis. Bile duct stenosis was detected in 56 patients (97%) with AIP with GB wall thickening. Intraductal ultrasonography indicated cystic duct wall thickening connected to bile duct wall thickening in 11 of 14 (79%) patients with AIP or IgG4-related sclerosing cholangitis with GB wall thickening. Forty-eight patients in whom IgG4-related cholecystitis was diagnosed experienced resolution of the GB wall thickening after receiving steroid therapy. CONCLUSIONS: Most cases of GB wall thickening in IgG4-related diseases are closely associated with IgG4-related sclerosing cholangitis and may be a manifestation of IgG4-related disease throughout the biliary tract, including the bile duct, cystic duct, and GB.

Focal parenchymal atrophy of pancreas: An important sign of underlying high-grade pancreatic intraepithelial neoplasia without invasive carcinoma, i.e., carcinoma in situ.

OBJECTIVES: Diagnosing high-grade intraepithelial neoplasia without invasion, traditionally referred to as carcinoma in situ (CIS), is essential for improving prognosis. We examined the imaging findings of patients with and without CIS to identify significant aspects for the diagnosis of CIS. METHODS: Forty-six patients strongly suspected of early pancreatic cancer without nodule on imaging (CIS group, n = 27; non-malignant group, n = 19) were retrospectively evaluated according to ten factors of computed tomography/magnetic resonance imaging (CT/MRI), endoscopic ultrasonography (EUS), and endoscopic retrograde cholangiopancreatography (ERCP) using hierarchical cluster and univariate analyses. RESULTS: Two clusters were formed by hierarchical cluster analysis. One cluster consisted of 83.3% CIS cases with similar image findings such as focal pancreatic parenchymal atrophy (FPPA) on CT/MRI, main pancreatic duct (MPD) stricture surrounded by hypoechoic areas on EUS, and MPD stricture with upstream MPD dilation on ERCP. On univariate analysis, the CIS and non-malignant groups had FPPA on CT/MRI in 15 (55.6%) and 3 (15.8%) cases (p = 0.013), and MPD stricture surrounded by hypoechoic areas on EUS in 20 (74.1%) and 4 (21.1%) cases (p = 0.001), respectively. MPD stricture surrounded by hypoechoic areas was observed in 80% (12/15) of CIS cases with FPPA on CT/MRI and correlated with FPPA. Moreover, FPPA and MPD stricture surrounded by hypoechoic areas had histopathologically observed fibrosis or fat replacement due to pancreatic parenchymal atrophy. CONCLUSIONS: FPPA and MPD stricture surrounded by hypoechoic areas are significant findings for the diagnosis of CIS.

Endoscopic Nasopancreatic Drainage Contributes to Early Resolution of Postgastrectomy Gastropancreatic Fistula.

A 76-year-old man experienced abdominal pain 43 days after gastric cancer resection. Computed tomography revealed a gastric wall defect extending to the pancreas, and endoscopic retrograde pancreatography revealed a gastropancreatic fistula. Afterward, a nasopancreatic duct drainage tube was inserted. Seven days later, no leakage of the contrast medium from the duct was observed, and the patient was discharged 22 days after endoscopic nasopancreatic duct drainage. Endoscopic nasopancreatic duct drainage prevents pancreatic juice leakage and promotes gastric ulcer healing.

Endoscopic Ultrasound Can Differentiate High-Grade Pancreatic Intraepithelial Neoplasia, Small Pancreatic Ductal Adenocarcinoma, and Benign Stenosis.

Background/Aims: High-grade pancreatic intraepithelial neoplasia and invasive pancreatic ductal adenocarcinoma ≤10 mm are targets for early detection of pancreatic cancer. However, their imaging characteristics are unknown. We aimed to identify endoscopic ultrasound findings for the detection of these lesions. Methods: Patients diagnosed with high-grade pancreatic intraepithelial neoplasia (n=29), pancreatic ductal adenocarcinoma ≤10 mm (n=11) (who underwent surgical resection), or benign main pancreatic duct stenosis (n=20) between January 2014 and January 2021 were retrospectively included. Six features differentiating these lesions were examined by endoscopic ultrasonography: main pancreatic duct stenosis, upstream main pancreatic duct dilation, hypoechoic areas surrounding the main pancreatic duct irregularities (mottled areas without demarcation or round areas with demarcation), branch duct dilation, prominent lobular segmentation, and atrophy. Interobserver agreement was assessed by two independent observers. Results: Hypoechoic areas surrounding the main pancreatic duct irregularities were observed more frequently in high-grade pancreatic intraepithelial neoplasia (82.8%) and pancreatic ductal adenocarcinoma ≤10 mm (90.9%) than in benign stenosis (15.0%) (p<0.001). High-grade pancreatic intraepithelial neoplasia exhibited mottled hypoechoic areas more frequently (79.3% vs 18.9%, p<0.001), and round hypoechoic areas less frequently (3.4% vs 72.7%, p<0.001), than pancreatic ductal adenocarcinoma ≤10 mm. The sensitivity and specificity of hypoechoic areas for differentiating high-grade pancreatic intraepithelial neoplasia, pancreatic ductal adenocarcinoma ≤10 mm, and benign stenosis were both 85.0%, with moderate interobserver agreement. Conclusions: The hypoechoic areas surrounding main pancreatic duct irregularities on endoscopic ultrasound may differentiate between high-grade pancreatic intraepithelial neoplasia, pancreatic ductal adenocarcinoma ≤10 mm, and benign stenosis (Trial Registration: UMIN Clinical Trials Registry (UMIN000044789).

Delayed bowel stenosis following subtotal resection of the small intestine for non-occlusive mesenteric ischemia.

We report herein a case of delayed bowel stenosis after surgery for non-occlusive mesenteric ischemia (NOMI), which was successfully treated with endoscopic stenting. The patient was a 78-year-old woman who underwent an emergency laparotomy for NOMI and duodeno-ileal anastomosis. Necrosis was observed in almost all areas of the small intestine except for the beginning of the jejunum and the end of the ileum. Postoperatively, the patient was discharged with central venous nutrition, but was readmitted on postoperative day 54 with a diagnosis of postoperative ileus. The patient failed to respond to conservative treatment. Fluoroscopic endoscopy revealed wall stiffness and circumferential stenosis in the ascending colon at a different site from that of the anastomosis. Based on this finding, delayed stenosis of the ascending colon after NOMI treatment was diagnosed. Bougie dilatation was performed for the stenosis, leading to temporary improvement. However, stenosis along with ileus soon recurred. To prevent restenosis, a metallic stent was endoscopically implanted at the stenotic site. Thereafter, the patient was discharged without any further episodes of restenosis. Delayed bowel stenosis may occur after a subtotal resection of the small intestine for NOMI. Endoscopic stenting is an effective treatment option if resection is difficult.

Duodenal Diverticular Perforation Treated Conservatively: Reassessing Indications for Treatment.

A 59-year-old woman presented with a chief complaint of melena. She had no abdominal findings, such as tenderness or tapping pain. Laboratory tests revealed a white blood cell count of 5,300 cells/µL and C-reactive protein level of 0.07 mg/dL. Inflammation and anemia (hemoglobin 12.4 g/dL) were denied. Contrast-enhanced computed tomography (CT) revealed multiple duodenal diverticula and air surrounding a descending duodenal diverticulum. Based on these findings, duodenal diverticular perforation (DDP) was suspected. Oral food intake was stopped, and nasogastric tube feeding and conservative treatment with cefmetazole, lansoprazole, and ulinastatin were begun. On day 8 of hospitalization, follow-up CT revealed the disappearance of the air surrounding the duodenum, and the patient was discharged on day 19 after the resumption of oral feeding.

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.

DNMT1 Expression and DNA Methylation in Intraductal Papillary Neoplasms of the Bile Duct.

BACKGROUND/AIM: Intraductal papillary neoplasms of the bile duct (IPNB) are histologically and clinically classified as type 1 and 2. This study aimed to identify the differences between these two types. MATERIALS AND METHODS: Based on multiple gene expression analysis (MGEA) using type 1, type 2, and pancreatic intraductal papillary mucinous neoplasms (n=4, 6, and 5, respectively), immunohistochemistry of DNMT1 and methylation-specific PCR for p16, APC, BRCA1, hMLH1, TIMP3, and SOX17 were performed on type 1 and 2 IPNBs (n=14, each). RESULTS: The DNMT1 protein was highly expressed (p<0.001) in 28.6% of type 1 cases and all type 2 cases. The DNA methylation ratio for the six genes in total as well as for SOX17 was lower in type 1 than in type 2 (p<0.05 each). CONCLUSION: Type 2 IPNB showed increased DNMT1 protein expression and increased DNA methylation frequency of the examined tumor suppressor genes compared to type 1. DNMT1 IHC may be helpful in discriminating between these two types.

Investigation of -PRKACA/-PRKACB fusion genes in oncocytic tumors of the pancreatobiliary and other systems.

Intraductal oncocytic papillary neoplasms (IOPNs) of the pancreatobiliary system are tumors comprising oncocytic cells, in which three types of fusion genes involving -PRKACA/-PRKACB were recently identified. IOPNs infrequently combine with other histological subtypes of pancreatic intraductal papillary mucinous neoplasms (IPMNs) and intraductal papillary neoplasms of the bile duct (IPNBs). This study aimed to confirm the sensitivity/specificity of the fusion genes for IOPNs and to examine their significance in other oncocytic lesions. An RT-PCR, followed by DNA sequencing, was undertaken to examine the fusions in 18 histologically diagnosed IOPNs, including four combined IOPNs. Moreover, in two IOPN cases, invasive carcinomatous lesions were separately examined on their fusion status. Oncocytic thyroidal (n = 10), renal (n = 10), and salivary gland (n = 3) lesions and IPMNs (n = 9)/IPNBs (n = 4) with focal oncocytic changes were examined as controls. Fluorescence in situ hybridization using PRKACA break-apart probes was conducted for the combined IOPN cases. Target sequencing of KRAS exon2/3 and GNAS exon 8/9 was performed for IOPN cases. Fusions were detected in all IOPN cases including invasive lesions/none of the control cases. The fusion event was confirmed also in non-IOPN component in one of the four combined cases. Regarding mutation events, 5.6%/0% of IOPNs were KRAS-mt/GNAS-mt, respectively, and both components of combined IOPNs were all KRAS-wt/GNAS-wt. In conclusion, our study confirmed the sensitivity and specificity of these fusions for IOPNs. Here, we analyzed the roles of these fusion genes in combined IOPNs, proposing the possibility of IOPN development via IPMNs/IPNBs. Further studies with more combined cases are warranted.

Pre-Operative Imaging and Pathological Diagnosis of Localized High-Grade Pancreatic Intra-Epithelial Neoplasia without Invasive Carcinoma.

Pancreatic ductal adenocarcinoma (PDAC) arises from precursor lesions, such as pancreatic intra-epithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasm (IPMN). The prognosis of high-grade precancerous lesions, including high-grade PanIN and high-grade IPMN, without invasive carcinoma is good, despite the overall poor prognosis of PDAC. High-grade PanIN, as a lesion preceding invasive PDAC, is therefore a primary target for intervention. However, detection of localized high-grade PanIN is difficult when using standard radiological approaches. Therefore, most studies of high-grade PanIN have been conducted using specimens that harbor invasive PDAC. Recently, imaging characteristics of high-grade PanIN have been revealed. Obstruction of the pancreatic duct due to high-grade PanIN may induce a loss of acinar cells replaced by fibrosis and lobular parenchymal atrophy. These changes and additional inflammation around the branch pancreatic ducts (BPDs) result in main pancreatic duct (MPD) stenosis, dilation, retention cysts (BPD dilation), focal pancreatic parenchymal atrophy, and/or hypoechoic changes around the MPD. These indirect imaging findings have become important clues for localized, high-grade PanIN detection. To obtain pre-operative histopathological confirmation of suspected cases, serial pancreatic-juice aspiration cytologic examination is effective. In this review, we outline current knowledge on imaging characteristics of high-grade PanIN.

Percutaneous pancreatic-duct puncture with rendezvous technique can treat stenotic pancreaticojejunostomy.

Stenotic pancreatico-enteric anastomosis is one of the serious late complications after a pancreaticoduodenectomy. We report a case of stenotic pancreaticojejunostomy with a pancreatic juice fistula drained externally, which was treated using percutaneous procedures combined with a rendezvous method. A 77-year-old woman was referred to our hospital for an endoscopic treatment to remove a percutaneous drainage tube from a fluid collection due to pancreatic juice fistula. She had undergone pylorus-preserving pancreatoduodenectomy with Roux-en-Y reconstruction due to duodenal carcinoma of Vater's papilla 1 year before the referral to our hospital. Soon after the operation, she had developed a fluid collection adjacent to the anastomosis due to pancreatic juice fistulas and subsequently had undergone its percutaneous drainage. After admission, we tried to dilate the stenotic anastomosis with an endoscopic procedure from the anastomosed jejunal lumen, using an oblique-viewing endoscope. The endoscope reached a portion of the anastomosis, but did not allow us to visualize the entire anastomosis. We punctured the main pancreatic duct under ultrasonography and fluoroscopy, and advanced the needle into the anastomosed jejunum through the stenotic anastomosis. After putting a guidewire into the anastomosed jejunum through the needle, we introduced an oblique-viewing endoscope into the anastomosed jejunum and caught hold of the guidewire using grasping forceps. Maintaining tension on the guidewire with a slight pulling force, with some effort we were able to place a 5-Fr drainage catheter into the jejunum percutaneously and through the anastomosis via the main pancreatic duct. Three weeks after these procedures, we performed balloon dilation of the anastomosis. One week after balloon dilation, removed the percutaneous catheter.

Pancreatic pseudocysts in post-gastrectomy patients treated via the duodenal minor papilla with an oblique-viewing endoscope.

Endoscopic retrograde cholangiopancreatography (ERCP) in patients after Billroth II or Roux-en-Y reconstruction is challenging because of difficulties in insertion of the endoscope into the afferent loop, which is a great distance away from the papilla of Vater, and cannulation into the desired duct from a reverse position. To facilitate ERCP, various endoscopes have been selected according to operator preference. Previously, we reported that an oblique-viewing endoscope (XK-200; Olympus, Tokyo, Japan) can contribute to successful performance of ERCP and associated procedures in Billroth II gastrectomy patients. We report here our experience with two post-gastrectomy patients with chronic pancreatitis who were treated with an oblique-viewing endoscope from the minor papilla.

Upregulation of follistatin and low apoptotic activity in intraductal oncocytic papillary neoplasm of the pancreatobiliary system.

Intraductal oncocytic papillary neoplasm (IOPN) is a rare intraductal tumor of the pancreatobiliary system. Currently, little is known about its distinct characteristics, unlike intraductal papillary mucinous neoplasms (IPMN) and intraductal papillary neoplasms of the bile duct (IPNB). The present study compared 22 IOPNs (18 pancreatic and 4 biliary) with those of 61 IPMNs/8 IPNBs. IOPNs were classified into pure and combined types, depending on the coexistence of IPMN/IPNB. Multiple gene expression analysis (nCounter system) was performed, and hierarchical clustering analysis separated IOPNs(n = 4) and IPMNs(n = 3)/ IPNBs(n = 3), and pathway score analysis supported the result. Volcano plot identified follistatin (FST) as the most upregulated mRNA in IOPN in comparison to the gastric subtype (log2 fold change of 5.34) and the intestinal subtype (that of 5.81) of IPMN/IPNB. The expression of FST in IOPN was also high in quantitative polymerase chain reaction and immunohistochemical analysis. We also found lower apoptotic activity in IOPN, particularly in pure type, compared to high-grade or invasive IPMN/IPNB using immunohistochemistry for cleaved caspase 3. But, combined type IOPN was more similar to IPMN/IPNB than pure IOPN. In conclusion, we proved that IOPN, particularly pure IOPN, is distinct from IPMN/IPNB in FST mRNA overexpression and exhibits lower apoptotic activity.

Carcinoma in situ of the pancreas with pancreatic duct stricture persistent for 4 years diagnosed by serial pancreatic juice aspiration cytologic examination (SPACE).

Serial pancreatic juice aspiration cytologic examination (SPACE) by nasopancreatic tube placement can give us an opportunity to diagnose early-stage pancreatic cancer with higher sensitivity and specificity compared with conventional pancreatic cytology by one-time pancreatic juice aspiration or pancreatic duct brushing. We performed SPACE in a patient with persistent pancreatic duct stricture (PDS) with gradually advancing pancreatic parenchyma atrophy (PPA) in the pancreas tail. The result of SPACE was suggestive of pancreatic carcinoma, and distal pancreatectomy was performed. Histopathological examination of the resected specimen revealed carcinoma in situ of the pancreas. The present case could indicate that any PDS becomes a candidate for SPACE especially in a patient with PPA, although the PDS remains unchanged for a long period.

Radiological and Pathological Assessment of the 2017 Revised International Association of Pancreatology Consensus Guidelines for Intraductal Papillary Mucinous Neoplasm, With an Emphasis on the Gastric Pyloric Gland Type.

OBJECTIVES: This study aimed to assess the pitfalls of the current International Association of Pancreatology guidelines (IAPCG2017) for pancreatic intraductal papillary mucinous neoplasm (IPMN) and identify the criteria for future guidelines. METHODS: Eighty surgically resected, consecutive IPMN cases were analyzed. Data including tumor site, IPMN duct type, and surgery type were collected. Based on radiological data, cases were retrospectively classified as high-risk stigmata (HRS) and non-HRS. Pathological grades and histological subtypes of IPMN cases were determined. Severe stromal sclerosis of the IPMN septa/marked parenchymal atrophy in the upstream pancreas was investigated pathologically. Positive/negative predictive values of the IAPCG2017 were calculated. Clinicopathological features of HRS-benign cases (pathologically benign IPMN cases meeting the HRS criteria) were extracted. RESULTS: The positive/negative predictive values were 72.7%/64.0%, 70.0%/34.6%, and 54.0%/63.3% for IAPCG2017, HRS-main pancreatic duct, and HRS-nodule criteria, respectively. The 15 HRS-benign cases (18.8%) included 13 pancreatoduodenectomies and 10 cases of gastric pyloric (GP) gland subtype. Severe upstream atrophy was significantly related to IPMN malignancy, unlike the severe sclerosis of IPMN septa. CONCLUSIONS: Benign IPMNs of GP subtype are sometimes categorized as HRS with the IAPCG2017. Collecting data on the natural course of GP-IPMN is necessary. To evaluate upstream atrophy may be of value to predict IPMN malignancy.