Combined pre-operative risk score predicts pancreatic leak after pancreatic resection.

BACKGROUND: Post-operative pancreatic fistula (POPF) is a major complication following pancreatectomy and is currently difficult to predict pre-operatively. This study aims to validate pre-operative risk factors and develop a novel combined score for the prediction of POPF in the pre-operative setting. METHODS: Data were collected from 2016 to 2021 for radiologic main pancreatic duct diameter (MPD), body mass index (BMI), physical status classified by American Society of Anesthesiologists (ASA), polypharmacy, mean platelet ratio (MPR), comorbidity-polypharmacy score (CPS), and a novel Combined Pancreatic Leak Prediction Score (CPLPS) (derived from MPD diameter, BMI, and CPS) were obtained from pre-operative data and analyzed for their independent association with POPF occurrence. RESULTS: In total, 166 patients who underwent pancreatectomy with pancreatic leak (Grade A, B, and C) occurring in 51(30.7%) of patients. Pre-operative radiologic MPD diameter < 4 mm (p < 0.001), < 5 mm (p < 0.001), < 6 mm (p = 0.001), BMI ≥ 25 (p = 0.009), and ≥ 30 (p = 0.017) were independently associated with the occurrence of pancreatic leak. CPLPS was also predictive of pancreatic leak following pancreatectomy on univariate (p = 0.005) and multivariate analysis (p = 0.036). CONCLUSION: MPD and BMI were independent risk factors predictive for the development of pancreatic leak. CPLPS, was an independent predictor of pancreatic leak following pancreatectomy and could be used to help guide surgical decision making and patient counseling.

[Modern endoscopic technologies for chronic calcifying pancreatitis]. / Sovremennye endoskopicheskie tekhnologii pri khronicheskom kal'tsinoznom pankreatite.

OBJECTIVE: To evaluate the effectiveness and safety of electrohydraulic lithotripsy of calculi of the main pancreatic duct using ultrathin SpyGlass DS endoscope. MATERIAL AND METHODS: The study included 29 patients with chronic calcifying pancreatitis and obstructive calculi of the main pancreatic duct. All surgeries were carried out between 2018 and 2023. RESULTS: Complete removal of calculi (≥5 mm) within one procedure was achieved in 25 (86%) patients. CONCLUSION: Pancreatoscopy with electrohydraulic lithotripsy using the digital SpyGlass DS system (BostonScientificCorp, Marlborough, MA) is the most effective method for calculi of the main pancreatic duct.

Focal pancreatic ductal change induced by 10-Fr S-type plastic stent in chronic pancreatitis.

BACKGROUND AND AIM: Stent-induced ductal change (SIDC) is a complication of endoscopic pancreatic stenting (EPS) in patients with chronic pancreatitis (CP). However, the evaluation of SIDC associated with S-type pancreatic plastic stent (PS) and large-caliber PS, such as 10 Fr, is limited. This study aimed to analyze the SIDC of the main pancreatic duct (MPD) associated with 10-Fr S-type PS in patients with CP. METHODS: Between January 2008 and December 2021, 132 patients with CP in whom a 10-Fr S-type PS had been installed by EPS were retrospectively reviewed. The SIDC incidence rate was examined, and the clinical features of patients with and without SIDC were investigated, including the outcomes for detected SIDC. RESULTS: Stent-induced ductal change during EPS was confirmed in 41 patients (31.1%) of 132 patients at a site coincident with the PS tip or distal flap in the MPD. All patients were asymptomatic during the development of SIDC. Morphological changes in the MPD were detected as elevated (75.6%) or bearing stricture changes (24.4%). A total of 90.2% of SIDC developed after the first 10-Fr PS installation. No significant differences were noted between the patients with and without SIDC. The outcomes of continued PS installment for SIDC showed persistence and secondary change. CONCLUSIONS: Stent-induced ductal change-associated 10-Fr PS installation was performed in just under one-third of the patients, indicating a substantial incidence rate and a possible development of SIDC from early stages onwards. More emphasis should be placed on SIDC as the complication.

Dilatation of the main pancreatic duct of unknown origin: causes and risk factors of pre-malignancy or malignancy.

INTRODUCTION: A dilatation of the main pancreatic duct (MPD) is mainly due to obstructive causes (pancreatic tumor, chronic pancreatitis) or intraductal papillary mucinous neoplasm (IPMN). This study aims to assess the risk of pre-malignancy or malignancy in case of MPD dilatation with no visible mass nor obstructive calcification on computed tomography scan (CT-scan) in a population operated for it. PATIENTS AND METHODS: All patients operated on from November 2015 to December 2019 in our center for a significant dilatation of the MPD without visible obstructive cause on CT-scan were included. Preoperative work-up included at least CT-scan, magnetic resonance imaging (MRI), and endoscopic ultrasonography (EUS). Primary endpoint was the final pathological diagnosis. Secondary endpoints were predictive factors of malignancy. RESULTS: 101 patients were included, mean age 68 years-old. Final pathological data were pancreatic adenocarcinoma (n = 2), IPMN with high-grade dysplasia (n = 37), high-grade Pancreatic Intraepithelial Neoplasia (PanIN) (n = 2) (total of pre-malignant or malignant lesions: n = 41), neuroendocrine tumor (n = 6), IPMN with low-grade dysplasia (n = 45), low-grade PanIN (n = 5), chronic pancreatitis (n = 3), and benign stenosis (n = 1). On preoperative explorations, the median diameter of MPD was 7 mm [3-35]. MRI and/or EUS showed intraductal material, nodule, or cyst in 22, 32, and 52 patients, respectively; 22 patients without nodule visible on MRI or EUS had still a pre-malignant or malignant lesion. In multivariate analysis, predictive factors for pre-malignancy or malignancy were symptoms before surgery (p = 0.01), MPD dilatation without downstream stenosis (p = 0.046), and the presence of nodule (p = 0.009). CONCLUSION: A dilatation of the MPD without detectable mass or obstructive calcification on CT-scan was associated with a pre-malignant or malignant lesion in 41 patients. Symptoms before surgery, MPD dilatation without duct narrowing, and the presence of nodules on MRI/EUS were associated with the risk of  pre-malignancy or malignancy.

The role of main pancreatic duct stent in the enucleation of benign/borderline pancreatic head tumors: a cohort study.

PURPOSE: This study aimed to reveal the role of preoperative main pancreatic duct (MPD) stent placement in reducing the intraoperative main pancreatic duct injury rate and the incidence of postoperative pancreatic leakage following pancreatic tumor enucleation. METHODS: A retrospective cohort analysis was performed for all patients with benign/borderline pancreatic head tumors who were treated with enucleation. The patients were divided into two groups (standard vs. stent) depending on whether they underwent main pancreatic duct stent placement prior to surgery. RESULTS: Thirty-three patients were finally included in the analytical cohort. Compared with the standard group, patients in the stent group had a shorter distance between tumors and main pancreatic duct (p=0.01) and presented with larger tumors (p<0.01). The rates of POPF (grade B&C) were 39.1% (9/23) and 20% (2/10) in the standard and stent groups, respectively (p<0.01). Major postoperative complications occurred more frequently in the standard group than in the stent group (14 versus 2; p<0.01). No significant differences in mortality, in-hospital stay or medical cost were observed between the two groups (p>0.05). CONCLUSIONS: MPD stent placement prior to surgery may facilitate pancreatic tumor enucleation, minimize MPD injury and decrease the occurrence of postoperative fistula.

Main Duct Thresholds for Malignancy Are Different in Intraductal Papillary Mucinous Neoplasms of the Pancreatic Head and Body-Tail.

BACKGROUND & AIMS: The risk of malignancy is uncertain for intraductal papillary mucinous neoplasms (IPMNs) with main pancreatic duct (MPD) of 5-9 mm. No study has correlated MPD size and malignancy considering the anatomic site of the gland (head versus body-tail). Our aim was to analyze the significance of MPD in pancreatic head/body-tail as a predictor of malignancy in main-duct/mixed IPMNs. METHODS: Retrospective analysis of resected patients between 2009-2018 was performed. Malignancy was defined as high-grade dysplasia and invasive carcinoma. MPD diameter was measured with magnetic resonance imaging. Receiver operating characteristic curve (ROC) analysis was utilized to identify optimal MPD cut-off for malignancy. Independent predictors of malignancy were searched. RESULTS: Malignancy was detected in 74% of 312 identified patients. 213 patients (68.3%) had IPMNs of the pancreatic head and 99 (31.7%) of the body-tail. ROC analysis identified 9 and 7 mm as the optimal MPD cut-offs for malignancy in IPMNs of head and body-tail of the pancreas, respectively. Multivariate analysis confirmed that MPD ≥9 mm (pancreatic head) and ≥7 mm (body-tail) were independent predictors of malignancy along with macroscopic solid components, positive cytology and elevated CA 19-9. The risk of malignancy was low for IPMNs with MPD ≤8 mm (pancreatic head) or ≤6 mm (pancreatic body-tail) unless high-risk stigmata or multiple worrisome features were present. CONCLUSIONS: Different thresholds of MPD dilation are associated with malignancy in IPMNs of the head and body-tail of the pancreas. The risk of malignancy for IPMNs with MPD ≤8 mm (pancreatic head) or ≤6 mm (pancreatic body-tail) lacking high-risk stigmata or multiple worrisome features is low.

Threshold of main pancreatic duct for malignancy in intraductal papillary mucinous neoplasm at head-neck and body-tail.

BACKGROUND: Main pancreatic duct (MPD) dilation is a high-risk stigmata/worrisome feature of malignancy in intraductal papillary mucinous neoplasms (IPMNs). The threshold of MPD diameter in predicting malignancy may be related to the lesion location. This study aimed to separately identify the thresholds of MPD for malignancy of IPMNs separately for the head-neck and body-tail. MATERIALS AND METHODS: A total of 185 patients with pathologically confirmed IPMNs were included. Patient demographic information, clinical data, and pathological features were obtained from the medical records. Those IPMNs with high-grade dysplasia or with associated invasive carcinoma were considered as malignant tumor. Radiological data including lesion location, tumor size, diameter of the MPD, mural nodule, and IPMN types (main duct, MD; branch duct, BD; and mixed type, MT), were collected on computed tomography or magnetic resonance imaging. Serum carbohydrate antigen 19-9 levels, serum carcinoembryonic antigen levels, and the medical history of diabetes mellitus, chronic cholecystitis, and pancreatitis were also collected. RESULTS: Malignant IPMNs were detected in 31.6% of 117 patients with lesions in the pancreatic head-neck and 20.9% of 67 patients with lesions in the pancreatic body-tail. In MPD-involved IPMNs, malignancy was observed in 54.1% of patients with lesions in the pancreatic head-neck and 30.8% of patients with lesions in the pancreatic body-tail (p < 0.05). The cutoff value of MPD diameter for malignancy was 6.5 mm for lesions in the head-neck and 7.7 mm for lesions in the body-tail in all type of IPMNs. In MPD-involved IPMNs, the threshold was 8.2 mm for lesion in pancreatic head-neck and 7.7 mm for lesions in the body-tail. Multivariate analysis confirmed that MPD diameter ≥ 6.5 mm (pancreatic head-neck) and MPD diameter ≥ 7.7 mm (pancreatic body-tail) were independent predictors of malignancy (p < 0.05). Similar results were observed in MPD-involved IPMNs using 8.2 mm as a threshold. CONCLUSION: The thresholds of the dilated MPD may be associated with IPMNs locations. Thresholds of 6.5 mm for lesions in the head-neck and 7.7 mm for lesions in the body-tail were observed. For MPD-involved IPMNs alone, threshold for lesions in the head-neck was close to that in the body-tail.

Anatomical pancreatic variants in intraductal papillary mucinous neoplasm patients: a cross-sectional study.

BACKGROUND: No previous studies have examined the possible relationship between intraductal papillary mucinous neoplasm (IPMN) and the developmental ductal variations of the pancreas, such as an ansa pancreatica and a meandering main pancreatic duct (MMPD). METHODS: This retrospective cross-sectional study enrolled 214 patients, 108 with IPMN disease and 106 subjects from a community at the tertiary care unit. The main pancreatic duct (MPD) was evaluated in the head of the pancreas by its course, which were non-MMPD: descending, vertical, and sigmoid, or MMPD including loop types, reverse-Z subtypes, and an N-shape, which was identified for the first time in this study. IPMN patients were also evaluated for worrisome features (WF) or high-risk stigmata (HRS), and the extent of IPMN cysts. RESULTS: Among IPMN patients, 18.4% had MMPD, which we observed in only 3.0% of the control group (P < 0.001). Patients with MMPD were more likely to belong to the IPMN group compared with non-MMPD patients [odds ratio (OR) 6.4, 95% confidence interval (CI) 2.2-24.9]. Compared with a descending shape MPD, IPMN patients with an N-shaped MPD were more likely to have a cystic mural nodule (OR 5.9, 95% CI 1.02-36.0). The presence of ansa pancreatica associated with more extent IPMN disease (OR 12.8, 95% CI 2.6-127.7). CONCLUSIONS: IPMN patients exhibited an MMPD more often than control patients. Ansa pancreatica associated with multiple cysts. Furthermore, an N-shape in IPMN patients associated with cystic mural nodules, suggesting that this shape serves as a risk factor for more severe IPMN.

Pancreatic ductal anatomy: more than meets the eye.

PURPOSE: Anatomical variations of the pancreas are relatively frequent and often understudied. The ductal system of the pancreas has multiple variations, which are not frequently reported in the literature. MATERIALS AND METHODS: The anatomy of the pancreas was studied through macroscopic anatomical dissection on 50 organ complexes (the pancreas, spleen, and duodenum) donated to the department of human anatomy, from patients, who died of causes not related to pancreatic diseases. RESULTS: In type I, the main pancreatic duct (Wirsung's duct, MPD) and the accessory pancreatic duct (Santorini's duct, APD) were merged but most of the head was drained by the MPD (10% of cases). In type II, the MPD and APD were merged but most of the head was drained by the APD (4% of cases). In type III, the APD was absent and the head was drained by the MPD (14% of cases). In type IV, there was an inverted pancreas divisum where the ducts did not merge but each drained a part of the head (6% of cases). Classical pancreas divisum where the ducts did not merge but each drained a part of the head was considered as type V (4% of cases). In type VI, the MPD and APD merged and each drained a part of the head (48% of cases). In type VII, the MPD and APD merged but the upper part of the head was drained by the main pancreatic duct (4% of cases). In type VIII, the MPD and APD merged but the lower part of the head was drained by the main pancreatic duct (4% of cases). In the IX type, the MPD and APD merged but the head was drained by the branches of the MPD (6% of cases). CONCLUSIONS: There are several drainage patterns of the pancreas. In some cases, one of the ducts provides more drainage of the gland than the other. This is clinically relevant since blockage of the main source of drainage leads to pancreatic juice stasis. It also explains cases when partial or total blockage of the duct results in the pancreatitis of an isolated zone.

Indication for resection and possibility of observation for intraductal papillary mucinous neoplasm with high-risk stigmata.

BACKGROUND/OBJECTIVES: According to the revised international intraductal papillary mucinous neoplasm (IPMN) guidelines (2017), the indication for surgery is based on risk classification. However, some IPMNs with high-risk stigmata (HRS) can be observed for long periods without resection. Hence, we need to reconsider the risk stratification, and this study aimed to propose a novel risk stratification for HRS-IPMNs. METHODS: We enrolled 328 patients diagnosed with IPMN using endoscopic ultrasound between 2012 and 2019. We compared clinicopathological features between HRS and worrisome features (WF) and evaluated outcomes of HRS-IPMN. RESULTS: Fifty-three patients (HRS 38, WF 15) underwent resection at initial diagnosis and 275 patients were observed. Following observation for 30 months, 22 patients (17 HRS, 5 WF) underwent resection. Analysis of resected IPMNs (n = 75) revealed that HRS had dominantly pancreatobiliary mucin subtype. Pancreatobiliary-type IPMN had larger nodule sizes and lymphatic invasion and high recurrence with poor prognosis. Seventy-four patients were diagnosed with HRS, 55 underwent resection, and 19 continue to be observed. The resected group had larger nodule sizes (median 8 mm vs. 5 mm; P = 0.060), whereas the observed group had more main pancreatic duct (MPD) dilation (median 10 mm vs. 5 mm; P = 0.005). In the resected HRS group, only patients with MPD dilation ≥10 mm (n = 10) had no recurrence but had a favorable prognosis compared with those nodule size ≥5 mm (n = 45). CONCLUSIONS: Large nodule size may be associated with pancreatobiliary subtype and poor prognosis; however, patients with MPD dilation ≥10 mm with nodule size <5 mm did not require resection.

Endoscopic ultrasound elastography for small solid pancreatic lesions with or without main pancreatic duct dilatation.

BACKGROUND: /Objectives: Endoscopic ultrasound elastography (EUS-EG) is useful for diagnosis of small solid pancreatic lesions (SPLs), particularly in excluding pancreatic cancer (PC), but its dependence on main pancreatic duct dilatation (MPDD) has not been examined. We aimed to investigate EUS-EG for diagnosis of small SPLs with and without MPDD. METHODS: Patients with pathologically diagnosed SPLs of ≤20 mm were included and retrospectively analyzed. Using the blue:green ratio, an EUS-EG image was classified as blue-dominant, equivalent, or green-dominant. Using multiple EUS-EG images per patient, a lesion with a greater number of blue-dominant than green-dominant images was classified as stiff, and the others as soft. EUS-EG images in random order were judged by three raters. Considering stiff SPLs as PC, diagnostic performance of EUS-EG was examined for SPLs with and without MPDD. RESULTS: Of 126 cases analyzed, 65 (52%) were diagnosed as PC, and 63 (50%) had MPDD. A total of 1077 EUS-EG images were examined (kappa coefficient = 0.783). Lesions were classified as stiff in 91 cases and soft in 35 (kappa coefficient = 0.932). The ratio of stiff to soft lesions was significantly higher in PC than in non-PC (62:3 vs. 29:32, P < 0.001). The sensitivity, specificity, and negative predictive value of a stiff lesion with vs. without MPDD for diagnosis of PC were 94%, 23%, and 50% vs. 100%, 60%, and 100%, respectively. CONCLUSIONS: Using the EUS-EG stiffness classification for small SPLs, PC can be excluded with high confidence and concordance for a soft lesion without MPDD.

A case of intraductal tubulopapillary neoplasm of the pancreas in a branch duct: a rare case report and literature review.

BACKGROUND: Intraductal tubulopapillary neoplasm (ITPN) of the pancreas is a new disease concept defined by the World Health Organization in 2010. ITPN progresses with tubulopapillary growth in the pancreatic duct and is known to have a fair prognosis. Localization in the main pancreatic duct (MPD) is one characteristic. There are few case reports of ITPN in a branch of the pancreatic duct (BD). CASE PRESENTATION: We encountered a case of ITPN localized in BD. An 85-year-old man was followed after colonic surgery for rectal carcinoma. An abdominal computed tomography scan revealed a cystic mass in the pancreatic head and further examination was done. A T2 weighted intension picture in magnetic resonance imaging showed a 20 mm cystic lesion with an internal mass of 15 mm. Duodenal papilla were slightly open and endoscopic retrograde pancreatography revealed mild and diffuse dilatation of the main pancreatic duct and mucin in the MPD. In consideration with the image examinations, we diagnosed the tumor as an intraductal papillary mucinous neoplasm with carcinoma because of its large mural nodule (> 10 mm in size) in a cyst. Consequently, a pancreaticoduodenectomy was performed. Macroscopically, a white solid tumor sized 2.5 × 1.8 × 1.0 was identified in the head of the pancreas. The cut surface of the resected pancreas showed a side-branch type intraductal tumor with tubulopapillary architecture without mucin secretion. Immunohistochemical staining was positive for MUC1, and negative for MUC2 and MUC5AC. The final diagnosis was determined to be pancreatic ITPN from BD. At the time of this report (48 months post-surgery), the patient remains disease-free without evidence of recurrence. CONCLUSION: ITPNs localized in BD are rare and diagnosis prior to surgery is difficult. In our case, the shape was round, not papillary, and with little fluid. These characteristics are different from a branch duct type IPMN and can be a clue to suspect ITPN in BD.

Clinical importance of main pancreatic duct variants and possible correlation with pancreatic diseases.

Background: Except for pancreas divisum (PD), the prevalence of anatomic variants of the main pancreatic duct (MPD) seems to be insufficiently investigated. To date, their role in the occurrence of pancreatic exocrine insufficiency (PEI) and morphological changes suggestive of chronic pancreatitis (CP) has remained unclear.Methods: A systematic review was performed, searching MEDLINE and Web of Science, limited to articles published between 1960 and 1 June 2019.Results: Our review included a total number of 3234 subjects. The most common variant of MPD was type 3, followed by type 1, indicating MPD drainage pattern into major papilla (MP) as the most frequent. A sub-variant of type 3, known as 'reverse pancreas divisum' had a prevalence of 2.2%. Type 4 variant- PD, was found in 6.4% of all cases. The most common sub-variant of PD was complete PD, followed by incomplete PD and variant with MPD as only pancreatic duct. Type 5 variant (including ansa pancreatica) was present in 2.9% of subjects. Apart from one study with a significantly higher frequency of morphological changes suggestive of CP in patients with ansa pancreatica, the studies stated no significant association between pancreatic disease and MPD variants. Furthermore, only one study examined the influence of MPD variants on exocrine pancreatic function. Although equivocal, this association is most likely found to be insignificant.Conclusion: To elucidate linkage between MPD variants and the occurrence of chronic pancreatitis and impairment of pancreatic exocrine function, further clinical investigations are warranted.

Prevention of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis by Endoscopic Pancreatic Stenting after Insertion of Self-Expandable Metal Stent for Malignant Distal Biliary Stricture.

The insertion of a self-expandable metal stent (SEMS) for nonpancreatic cancer is a factor predicting the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). We evaluated the efficacy of endo-scopic pancreatic stenting (EPS) to prevent PEP after SEMS insertion in patients with malignant distal biliary stricture and without main pancreatic duct (MPD) obstruction. We performed a single-center, retrospective, historically controlled investigation to assess the outcomes of 33 consecutive patients who underwent SEMS insertion. From March 2013 to June 2015, 13 patients did not undergo EPS (Non-EPS group). The other 20 patients underwent EPS (EPS group) between July 2015 and August 2018. The background data demonstrated no significant differences. Except for one patient in the Non-EPS group, all patients underwent biliary sphinc-terotomy. The EPS group's PEP incidence was significantly lower (n = 1, 5%) than that of the Non-EPS group (n = 4, 31%) (p = 0.04). The median serum amylase and lipase levels after the procedure were significantly lower in the EPS group than in the Non-EPS group (amylase: 104 vs. 262 U/L; p < 0.01, lipase: 102 vs. 666 U/L; p = 0.01). The use of EPS decreased the incidence of PEP after SEMS insertion in individuals with malignant distal biliary stricture and without MPD obstruction.

Clinical significance of the preoperative main pancreatic duct dilation and neutrophil-to-lymphocyte ratio in pancreatic neuroendocrine tumors (PNETs) of the head after curative resection.

BACKGROUND: The present study aimed to investigate the prognostic significance of preoperative main pancreatic duct dilation and the neutrophil-to-lymphocyte ratio (PD-NLR) in pancreatic neuroendocrine tumors (PNETs) of the head after curative resection. METHODS: Sixty-four consecutive PNETs of the head that underwent curative resection were included in the study. Preoperative main pancreatic duct dilation (PD) was defined as a pancreatic duct dilation greater than 3 mm before surgery. Patients with both PD and an elevated NLR (> 3.13), with PD or elevated NLR, or neither of these characteristics were allocated a PD-NLR score of 2, 1, or 0, respectively. Univariate, multivariate and Kaplan-Meier analyses were used to calculate overall survival (OS) and disease-free survival (DFS). RESULTS: Preoperative PD-NLR score was correlated with tumor size (P = 0.005), T-stage (P = 0.016), lymph node metastasis (P <  0.001), distant metastasis (P = 0.005), type of hormone production (P = 0.006), perineural invasion (P = 0.014), and WHO classification (P <  0.001). Patients with a high PD-NLR score had a significantly poor OS and DFS relative to those with a low PD-NLR score (P <  0.001). In the multivariate analysis, PD-NLR score was an independent predictor of OS and DFS for PNET of the head (both P <  0.05). In the analyses of the various subgroups, preoperative PD-NLR score was also a predictor of OS and DFS. Additionally, the survival predictive capability of PD-NLR score was superior to that of WHO classification. CONCLUSIONS: Despite the retrospective nature and small sample size of the present study, the results suggest that preoperative PD-NLR score can serve as an independent prognostic marker of early survival in patients with PNETs of the head undergoing curative resection. Further large prospective studies are necessary to validate our findings.

The uncommon loop: Circumportal annular pancreas.

Circumportal annular pancreas (CAP) also known as portal annular pancreas (PAP) is an uncommon pancreatic anatomic variant in which normal pancreatic tissue completely surrounds the portal vein and can be mistaken for mass of pancreatic head. We present here a case of a 65 years old woman who was a diagnosed case of endometrial carcinoma, underwent CT scan for further metastatic workup which revealed this rare pancreatic variant.

Detection of High-Grade Pancreatic Intraepithelial Neoplasia without Morphological Changes of the Main Pancreatic Duct over a Long Period: Importance for Close Follow-Up for Confirmation.

Pancreatic intraepithelial neoplasia (PanIN) is a microscopic papillary noninvasive lesion arising from the pancreatic ductal epithelium. However, the natural history and time to progression of high-grade PanIN remain unclear. Herein, we report 2 cases of high-grade PanIN without morphological changes of the main pancreatic duct (MPD) over relatively long periods. In the first case, a 63-year-old man was identified with MPD dilation. Magnetic resonance cholangiopancreatography showed localized stenosis in the pancreatic body with distal MPD dilation. Endoscopic retrograde pancreatography (ERP) was attempted because of possible high-grade PanIN but was unsuccessful. At 15-month follow-up, there was no change in the form of the MPD in various images. However, ERP was re-performed because of possible high-grade PanIN, and cytology showed adenocarcinoma. Postoperative pathology indicated diffuse lesions corresponding to high-grade PanINs in the MPD stenosis and surrounding branches. Final diagnosis was high-grade PanIN. In the second case, a 77-year-old man was identified with MPD dilation. Magnetic resonance cholangiography showed localized stenosis in the MPD of the pancreatic head with distal MPD dilation. He was diagnosed with MPD stenosis caused by chronic pancreatitis, and further examination was not recommended. At 25 months, the patient was referred to our hospital because of a mild change in MPD dilation. ERP showed localized irregular stenosis in the MPD, and cytology showed suspected adenocarcinoma. Postoperative pathology indicated a localized lesion with high-grade PanIN in the branch duct around the MPD stenosis. Final diagnosis was high-grade PanIN. In conclusion, we report 2 cases of high-grade PanIN without morphological changes of the MPD over relatively long periods. Even if a definite diagnosis is not obtained at initial examination, a strict follow-up observational study should be performed. Re-examination, including ERP, should also be considered in cases with risk factors of pancreatic cancer, even if there is no change in MPD form.

Isolated Main Pancreatic Duct Dilatation: CT Differentiation Between Benign and Malignant Causes.

OBJECTIVE: The purpose of this study is to retrospectively evaluate the differential CT features of isolated benign and malignant main pancreatic duct (MPD) dilatation and to investigate whether the diagnostic performance of radiologists can be improved with knowledge of these differential CT features. MATERIALS AND METHODS: Forty-one patients who had isolated MPD dilatation without any visible mass on CT from January 2000 to October 2016 were retrospectively enrolled in the study. Two radiologists reviewed CT images in consensus for the location, shape (smooth vs abrupt), length of transition, dilated pancreatic duct (PD) diameter, presence of duct penetrating sign, parenchymal atrophy, attenuation difference, associated pancreatitis, calcification, PD or common bile duct (CBD) enhancement, and perilesional cyst. The chi-square test, Fisher exact test, and t test were used to find the differential CT features of benign and malignant MPD dilatation. Two successive review sessions for differentiation between the two disease entities were then independently performed by three other reviewers with differing expertise, with the use of a 5-point confidence scale. The first session provided no information for differentiation; however, reviewers were aware of the results of univariate analyses in the second session. The diagnostic performance of the radiologists was evaluated using a pairwise comparison of ROC curves. RESULTS: A total of 19 benign and 22 malignant MPD dilatations were identified. In patients with benign MPD dilatation, transition areas were frequently located in the head (57.9% [11/19] vs 13.6% [3/22], p = 0.003) and showed significantly shorter (< 6.1 mm) (78.9% [15/19] vs 9.1% [2/22], p < 0.0001) and smooth transition (89.5% [17/19] vs 9.1% [2/22], p < 0.0001). Duct penetrating sign was exclusively observed in patients with benign MPD dilatation (73.7% [14/19] vs 0% [0/22], p < 0.0001). In contrast, malignant MPD dilatation frequently was accompanied by attenuation difference (63.6% [14/22] vs 10.5% [2/19], p = 0.001) and associated PD or CBD enhancement (36.4% [8/22] vs 0% [0/19], p = 0.003). The AUC values of three reviewers significantly increased from 0.653, 0.587, and 0.884 to 0.864, 0.964, and 0.908, respectively, with knowledge of significant CT features (p = 0.013, p < 0.0001, and p = 0.701, respectively). CONCLUSION: Distal, long (≥ 6.1 mm), and abrupt transition, the absence of duct penetrating sign, and the presence of attenuation difference and PD or CBD enhancement were highly suggestive CT findings for differentiation of malignant from benign MPD dilatation. The diagnostic performance of radiologists with regard to differentiation was significantly improved with knowledge of these highly suggestive CT criteria.

Three-dimensional simulation of pancreatic surgery showing the size and location of the main pancreatic duct.

PURPOSE: We performed three-dimensional (3D) surgical simulation of pancreatic surgery, including the size and location of the main pancreatic duct on the resected pancreatic surface. METHODS: The subjects of this retrospective analysis were 162 patients who underwent pancreatic surgery. This cohort was sequentially divided into a "without-3D" group (n = 81) and a "with-3D" group (n = 81). We compared the pancreatic duct diameter and its location, using nine sections in a grid pattern, with the intraoperative findings. The perioperative outcomes were also compared between patients who underwent pancreaticoduodenectomy (PD) and those who underwent distal pancreatectomy (DP). RESULTS: There were no significant differences in the main pancreatic duct diameter between the 3D-simulated values and the operative findings. The 3D-simulated main pancreatic duct location was consistent with its actual location in 80 % of patients (65/81). In comparing the PD and DP groups, the intraoperative blood loss was 1174 ± 867 and 817 ± 925 ml in the without-3D group, and 828 ± 739 and 307 ± 192 ml in the with-3D group, respectively (p = 0.024, 0.026). CONCLUSION: The 3D surgical simulation provided useful information to promote our understanding of the pancreatic anatomy, including details on the size and location of the main pancreatic duct.

Closed loop of main duct of pancreas: a rare variant configuration.

During routine dissection, duplication of main pancreatic duct extending from body to head region of pancreas was observed in a 78-year-old formalin fixed male cadaver. Main pancreatic duct gave a prominent branch which joined back the parent duct in head resulting in the formation of a closed loop. This gave the appearance of focal duplication in the form of a closed loop, an unusual variant. This was an incidental finding. Such cases usually remain asymptomatic; however, if undetected may be the cause of postoperative pancreatic fistula following pancreaticobiliary surgery. Knowledge of variable anatomy of pancreatic duct system became important to reduce the risk of postoperative complication and during various endoscopic guided procedures like drainage of pseudocyst or placement of stent into the duct.