Main pancreatic duct involved IPMN without high-risk factors: how to judge the degree of malignancy based on MPD dilation?

The aim of this study was to evaluate the cutoff value for identifying malignance in main pancreatic duct (MPD)-involved intraductal papillary mucinous neoplasm (IPMN) with an MPD diameter ranging from 5 to 10 mm. Clinical-radiological characteristics of 142 patients, including MPD-involved IPMNs (n = 53) and branch-duct (BD)-IPMNs (n = 89) were analyzed. Logistic regression analysis was used to determine the risk factors of malignant IPMNs and invasive carcinoma. ROC curves were used to identify different cutoffs in terms of preoperative MPD values to predict the presence of invasive carcinoma as well as malignant IPMNs, and the prediction performance was evaluated. For MPD-involved IPMNs (5 mm < MPD < 10 mm), MPD diameter of 7.5 mm for discriminating malignant IPMNs (area under curve [AUC] = 0.67) and 7.7 mm for discriminating invasive IPMNs (AUC = 0.56) were found to be the optimal cutoff values at receiver operating characteristic curve (ROC) analysis. MPD > 7.5 mm and carbohydrate antigen19-9 (Ca19-9) > 37 U/ml were found to be predictors of malignant IPMNs at univariate, and MPD > 7.5 mm was a predictor in multivariate analysis in MPD-involved IPMNs. The AUC of the ROC curve of MPD (7.5 mm) combined with Ca19-9 in identifying malignant IPMNs was 0.73 in MPD-involved IPMNs. MPD (7.5 mm) combined with Ca19-9 performed well in identifying malignant IPMNs in MPD-involved IPMNs.

Intraductal and cystic pancreatic neoplasia.

The current WHO classification of digestive system tumours (2019) has presented the concept of diagnostics of intraductal and cystic neoplasms of the pancreas mostly based on integrated molecular data and evaluations of their malignant potential. Intraductal pancreatic neoplasms with ductal phenotype include microscopic precursor lesions of pancreatic ductal adenocarcinoma - the pancreatic intraepithelial neoplasia and macroscopic precursor lesions of pancreatic cancer, where intraductal papillary mucinous neoplasm represents the most common neoplasm of the pancreas with cystic appearance. Both intraductal oncocytic papillary neoplasm and intraductal tubulopapillary neoplasm are now classified as separate entities associated with less aggressive subtypes of pancreatic carcinoma and better prognosis. Clinical significance of microscopic pancreatic intraepithelial neoplasias is limited, in contrast to other intraductal neoplasms, which are presented as cystic and/or solid tumours by imaging methods with important consequences for further treatment and indication of surgical therapy (resection versus "watch and wait" strategies). Neoplasms of nonductal origin, such as acinar cell carcinomas and neuroendocrine neoplasms, can uncommonly display an intraductal growth and their correct classification has a great clinical importance. Moreover, differential diagnostics of cystic pancreatic lesions include not only cystic and pseudocystically transformed neoplasms, but also a large spectrum of reactive, inflammatory and dysontogenetic cystic lesions.

Repeated Minimally Invasive Pancreatectomy for Intraductal Papillary Mucinous Neoplasm in the Remnant Pancreas: A Case Report.

BACKGROUND Minimally invasive pancreatectomy has become the standard practice for the management of benign and malignant pancreatic tumors. Techniques such as robotic and laparoscopic approaches are known to reduce morbidity by offering benefits such as less blood loss, reduced pain, shorter hospital stays, and quicker recovery times. The indication for repeated minimally invasive pancreatectomy for recurrent or de novo pancreatic neoplasm after primary pancreatic surgery remains debated. CASE REPORT A 50-year-old woman was admitted to our hospital with a diagnosis of an intraductal papillary mucinous neoplasm in the pancreatic head. In 2010, she underwent laparoscopic single-branch resection for a branch-type tumor in the pancreatic uncinate process. During a 5-year follow-up, a de novo intraductal papillary mucinous neoplasm was detected, showing gradual growth and the presence of a mural nodule over the next 7 years. The patient's CEA level was elevated to 7.0 ng/mL. Considering the tumor's progression and the appearance of a mural nodule, we recommended a robot-assisted Whipple procedure. The operation began with laparoscopic adhesiolysis. After detachment of the adhesions and remobilization of the duodenum using the Kocher maneuver, the operation continued with the Da Vinci surgical system. The postoperative period was uneventful, and the patient was discharged on postoperative day 20. Pathological examination revealed intraductal papillary mucinous carcinoma in situ with negative resection margins. CONCLUSIONS This case verifies the safety and feasibility of performing a robotic Whipple procedure for a newly diagnosed pancreatic neoplasm in patients who have previously undergone minimally invasive pancreatic surgery.

[A Case of Pulmonary Nontuberculous Mycobacterial Infection Accompanied with Intraductal Papillary Mucinous Neoplasm].

An 87-year-old woman presented to the emergency department with left thigh pain, and sciatic nerve pain was diagnosed. A chest CT scan showed bronchiectasis and tree-in buds and an acid-fast stain test of gastric juice was positive; further, M. avium-PCR of sputum and culture results were positive leading to a diagnosis of pulmonary nontuberculous mycobacterial infection(NTM). Abdominal CT showed dilatation of the main pancreatic duct and a multifocal cystic tumor in the pancreatic tail, which was found to be complicated with an intraductal papillary mucinous tumor(IPMN).

Comprehensive analysis of clinical data and radiomic features from contrast enhanced CT for differentiating benign and malignant pancreatic intraductal papillary mucinous neoplasms.

The primary aim of this investigation was to leverage radiomics features derived from contrast-enhanced abdominal computed tomography (CT) scans to devise a predictive model to discern the benign and malignant nature of intraductal papillary mucinous neoplasms (IPMNs). Radiomic signatures were meticulously crafted to delineate benign from malignant IPMNs by extracting pertinent features from contrast-enhanced CT images within a designated training cohort (n = 84). Subsequent validation was conducted with data from an independent test cohort (n = 37). The discriminative ability of the model was quantitatively evaluated through receiver operating characteristic (ROC) curve analysis, with the integration of carefully selected clinical features to improve the comparative analysis. Arterial-phase images were utilized to construct a model comprising 8 features for distinguishing between benign and malignant cases. The model achieved an accuracy of 0.891 [95% confidence interval (95% CI), 0.816-0.996] in the cross-validation set and 0.553 (95% CI 0.360-0.745) in the test set. Conversely, employing 9 features from the venous-phase resulted in a model with a cross-validation accuracy of 0.862 (95%CI 0.777-0.946) and a test set accuracy of 0.801 (95% CI 0.653-0.950).Integrating the identified clinical features with imaging features yielded a model with a cross-validation accuracy of 0.934 (95% CI 0.879-0.990) and a test set accuracy of 0.904 (95% CI 0.808-0.999), thereby further improving its discriminatory ability. Our findings distinctly illustrate that venous-phase radiomics features eclipse arterial-phase radiomic features in terms of predictive accuracy regarding the nature of IPMNs. Furthermore, the synthesis and meticulous screening of clinical features with radiomic data significantly increased the diagnostic efficacy of our model, underscoring the pivotal importance of a comprehensive and integrated approach for accurate risk stratification in IPMN management.

Dilated common bile duct is commonly associated with main duct Intraductal Papillary Mucinous Neoplasm of the pancreas.

BACKGROUND: Dilatation of common bile duct (CBD) is mostly pathological and mainly occurs secondary to mechanical causes. We aimed to explore the prevalence of CBD dilatation in Intraductal Papillary Mucinous Neoplasms of the pancreas (IPMN) among patients referred to EUS. METHODS: A retrospective study of all patients who had an EUS diagnosis of IPMN from 2011 to 2019 at Galilee Medical Center were extracted. Control group including patients with other types of pancreatic cysts. RESULTS: Overall, 2400 patients were included in the study, of them 158 patients were diagnosed with pancreatic cysts, 117 patients (74%) diagnosed with IPMN (group A), and 41 patients (26%) diagnosed with other pancreatic cysts (group B). Univariate analysis showed significant association of IPMN (OR 3.8, 95% CI 1.3-11.5), resected gallbladder (GB) (OR 7.75, 95% CI 3.19-18.84), and age (OR 1, 95% CI 1.01-1.08) with CBD dilatation. Classifying IPMN to sub-groups using adjusted multivariate logistic regression analysis, only main duct-IPMN (MD-IPMN) significantly correlated with CBD dilatation compared to branch duct (BD)-IPMN and mixed type-IPMN (OR 19.6, 95% CI 4.57-83.33, OR 16.3, 95% CI 3.02-88.08). CONCLUSION: MD-IPMN was significantly correlated with dilated CBD. Assessment of the pancreas is warranted in encountered cases of dilated CBD without obvious mechanical cause.

Molecular and morphologic characterization of intraductal tubulopapillary neoplasms of pancreas with novel potentially targetable fusions.

Intraductal tubulopapillary neoplasms (ITPNs) are rare pancreatic tumors with distinct histological and molecular features. Distinction of ITPN from other pancreatic neoplasms is crucial given the known favorable prognosis and the high frequency and diversity of potentially targetable fusions in ITPN. While the histological features of ITPN are well documented, there are few reports on the cytological features, and molecular characterization of ITPN. The authors reported three cases diagnosed in their laboratory between 2016 and 2021. Clinical data, cytomorphological and histological features, with immunophenotypic and molecular characterizations of these cases are described and compared with those reported in the literature. All 3 cases were diagnosed as ITPN based on the microscopic presence of intraductal nodules composed of tightly packed small tubular glands lined by cuboidal cells lacking apparent mucin. On molecular profiling KRAS and TP53 variants were found in Case 1, FGFR2-INA fusion in Case 2, and STARD3NL-BRAF fusion was detected in Case 3. Immunohistochemistry (IHC) revealed that the neoplastic cells in Case 1 were MUC2 positive and MUC6 negative, but in Cases 2 and 3, were negative for MUC2 and positive for MUC6. These results demonstrate the immunophenotypic and molecular variabilities of histologically similar pancreatic neoplasms. The absence of alterations characteristic of more common pancreatic neoplasms should prompt the consideration of fusion studies in morphologically relevant cases. The combination of morphological, IHC, and molecular analyses is important for reliable identification of ITPN given its potential clinical management implications.

Predictors of long-term survival after resection of adenocarcinoma arising from intraductal papillary mucinous neoplasm and derivation of a prognostic model: An international multicenter study (ADENO-IPMN study).

BACKGROUND: Predictors of long-term survival after resection of adenocarcinoma arising from intraductal papillary mucinous neoplasms are unknown. This study determines predictors of long-term (>5 years) disease-free survival and recurrence in adenocarcinoma arising from intraductal papillary mucinous neoplasms and derives a prognostic model for disease-free survival. METHODS: Consecutive patients who underwent pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasms in 18 academic pancreatic centers in Europe and Asia between 2010 to 2017 with at least 5-year follow-up were identified. Factors associated with disease-free survival were determined using Cox proportional hazards model. Internal validation was performed, and discrimination and calibration indices were assessed. RESULTS: In the study, 288 patients (median age, 70 years; 52% male) were identified; 140 (48%) patients developed recurrence after a median follow-up of 98 months (interquartile range, 78.4-123), 57 patients (19.8%) developed locoregional recurrence, and 109 patients (37.8%) systemic recurrence. At 5 years after resection, the overall and disease-free survival was 46.5% (134/288) and 35.0% (101/288), respectively. On Cox proportional hazards model analysis, multivisceral resection (hazard ratio, 2.20; 95% confidence interval, 1.06-4.60), pancreatic tail location (hazard ratio, 2.34; 95% confidence interval, 1.22-4.50), poor tumor differentiation (hazard ratio, 2.48; 95% confidence interval, 1.10-5.30), lymphovascular invasion (hazard ratio, 1.74; 95% confidence interval, 1.06-2.88), and perineural invasion (hazard ratio, 1.83; 95% confidence interval, 1.09-3.10) were negatively associated with long-term disease-free survival. The final predictive model incorporated 8 predictors and demonstrated good predictive ability for disease-free survival (C-index, 0.74; calibration, slope 1.00). CONCLUSION: A third of patients achieve long-term disease-free survival (>5 years) after pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasms. The predictive model developed in the current study can be used to estimate the probability of long-term disease-free survival.

Optimization of Endoscopic Ultrasound Characteristics in the Diagnosis of Malignant Intraductal Papillary Mucinous Neoplasm.

OBJECTIVES: Endoscopic ultrasound (EUS) is an excellent diagnostic tool that provides high-resolution images of pancreatic cystic lesions. However, its role in the diagnosis of malignant intraductal papillary mucinous neoplasm (IPMN) remains limited and unclear. We aimed to determine the usefulness of this modality for such diagnosis. METHODS: Overall, 246 patients who underwent EUS for IPMN after computed tomography (CT)/magnetic resonance imaging (MRI) from April 2018 to June 2021 were followed up until March 2022. We assessed the added value of performing EUS after CT or MRI for diagnosing malignant IPMN, using receiver operating characteristic curve analysis. Walls as thick as 2 mm were considered thickened in this study if they were highly uneven. RESULTS: EUS clearly enhanced accuracy in identifying enhancing nodules and thickened walls. The areas under the receiver operating characteristic curve and corresponding 95% confidence intervals were 0.655 (0.549-0.760) and 0.566 (0.478-0.654) upon CT/MRI but 0.853 (0.763-0.942) and 0.725 (0.634-0.817) when observed using EUS. The combination of nodule size, thickened wall, and main duct size yielded the highest area under the receiver operating characteristic curve (0.944 [0.915-0.973]). CONCLUSIONS: EUS more accurately detects malignant IPMN, as uneven wall thickening and certain nodules cannot be identified with CT/MRI.

PRKACA/PRKACB Fusions in Pancreatobiliary Intraductal Oncocytic Papillary Neoplasms Including Those With Atypical Morphology: An Analysis of 22 Cases Expanding Morphologic Spectrum.

Intraductal oncocytic papillary neoplasms (IOPNs) of the pancreatobiliary tract are considered a separate entity from intraductal papillary mucinous neoplasms (IPMNs), especially because of the distinct molecular alterations represented by PRKACA or PRKACB fusion. However, IOPNs display a spectrum of cytoarchitectural features. Typically, an IOPN is composed of arborizing papillae lined by layers of cells with oncocytic cytoplasm, prominent nucleoli, and intraepithelial lumina, while a significant subset shows atypical morphology: lack of the characteristic cytoarchitectural features such as arborizing papillae and prominent nucleoli, or mixture with nononcocytic IPMN-like components within a single lesion. To elucidate the tumorigenesis and morphologic spectrum of IOPNs, we analyzed 22 IOPNs, including those with atypical morphology for PRKACA/PRKACB fusions in each different component separately using fluorescence in situ hybridization. In total, 18 of 22 (82%) cases harbored PRKACA/PRKACB fusions, including 3 of 3 (100%) purely typical IOPNs and 15 of 19 (79%) IOPNs with atypical morphology. In the latter, PRKACA/PRKACB fusions were noted in atypical components as well as typical IOPN components. Notably, gastric-type IPMN-like components in the fusion-positive cases were usually low grade and had scattered neoplastic cells with eosinophilic cytoplasm, a morphologic feature suggestive of an early lesion of IOPN. In summary, most IOPNs with atypical morphology either lack characteristic cytoarchitectural features or exhibit a mixture with nononcocytic IPMN-like components, harbored PRKACA/PRKACB fusion as did typical IOPN components. Our observations expanded the morphologic spectrum of IOPNs. They are expected to be useful for correct diagnosis of this neoplasm.

PanIN or IPMN? Redefining Lesion Size in 3 Dimensions.

Pancreatic ductal adenocarcinoma (PDAC) develops from 2 known precursor lesions: a majority (∼85%) develops from pancreatic intraepithelial neoplasia (PanIN), and a minority develops from intraductal papillary mucinous neoplasms (IPMNs). Clinical classification of PanIN and IPMN relies on a combination of low-resolution, 3-dimensional (D) imaging (computed tomography, CT), and high-resolution, 2D imaging (histology). The definitions of PanIN and IPMN currently rely heavily on size. IPMNs are defined as macroscopic: generally >1.0 cm and visible in CT, and PanINs are defined as microscopic: generally <0.5 cm and not identifiable in CT. As 2D evaluation fails to take into account 3D structures, we hypothesized that this classification would fail in evaluation of high-resolution, 3D images. To characterize the size and prevalence of PanINs in 3D, 47 thick slabs of pancreas were harvested from grossly normal areas of pancreatic resections, excluding samples from individuals with a diagnosis of an IPMN. All patients but one underwent preoperative CT scans. Through construction of cellular resolution 3D maps, we identified >1400 ductal precursor lesions that met the 2D histologic size criteria of PanINs. We show that, when 3D space is considered, 25 of these lesions can be digitally sectioned to meet the 2D histologic size criterion of IPMN. Re-evaluation of the preoperative CT images of individuals found to possess these large precursor lesions showed that nearly half are visible on imaging. These findings demonstrate that the clinical classification of PanIN and IPMN fails in evaluation of high-resolution, 3D images, emphasizing the need for re-evaluation of classification guidelines that place significant weight on 2D assessment of 3D structures.

[A rare case of intraductal tumor of the pancreas in which an intraductal tubulopapillary neoplasm was mixed with a widely spreading gastric-type intraductal papillary-mucinous neoplasm].

A 70-year-old man receiving treatment for diabetes mellitus presented with a cystic mass in the border area of the pancreatic body and tail on plain computed tomography (CT) due to impaired glucose intolerance. Contrast-enhanced CT showed a faint hyperattenuated nodular mass extending from the dilated main pancreatic duct (MPD) to the branch duct. Endoscopic retrograde cholangiopancreatography revealed a mildly dilated orifice of the papilla of Vater and MPD stenosis with entire upstream and immediate downstream dilatations. The patient underwent distal pancreatectomy due to the suspicion of mixed-type intraductal papillary-mucinous carcinoma. A pathological examination showed an intraductal solid-nodular mass measuring 25mm in length, consisting of two types of neoplasms. One showed tubulopapillary growth with entirely high-grade (HG) atypical cuboidal epithelium, in which immunohistochemical examinations were positive for MUC6 but negative for human gastric mucin (HGM), MUC1, MUC2, and MUC5AC, fitting the concept of intraductal tubulopapillary neoplasm (ITPN). The other showed the same growth of low-grade (LG) atypical columnar cells positive for HGM and MUC5AC and negative for MUC1 and MUC2, which corresponded to gastric-type intraductal papillary-mucinous neoplasm (IPMN) -LG. The tumor had not invaded the duct walls, and no metastatic lymph nodes were observed. The ITPN was adjacent to the IPMN mainly composed of tubular glands mimicking pyloric glands with LG dysplasia that corresponded to the so-called IPMN-pyloric gland variant. Moreover, the proliferation of low-papillary gastric-type IPMN spread around the intraductal tumors. Consequently, the patient was diagnosed with an intraductal tubular neoplasm comprising a noninvasive ITPN and gastric-type IPMN-LG. ITPN is a recently identified intraductal neoplasm of the pancreas proposed by Yamaguchi et al. and is distinguished by intraductal tubulopapillary growth with HG cellular atypia without overt mucin production, in contrast to IPMN. To date, no cases of intraductal nodular tumors comprising ITPN and IPMN have been reported. We report this original case with imaging and pathological observations and discuss potential processes via which ITPN and IPMN may arise adjacent to each other in the same pancreatic duct.

Pancreatoscopy-Guided Endotherapies for Pancreatic Diseases.

Per-oral pancreatoscopy (POP) is a pancreas-preserving modality that allows for targeted pancreatic duct interventions, particularly in cases where standard techniques fail. POP specifically has an emerging role in the diagnosis, risk stratification, and disease extent determination of main duct intraductal papillary mucinous neoplasms (IPMNs). It has also been successfully used for laser ablation of IPMNs in poor surgical candidates, lithotripsy for complex stone disease, and laser stricturoplasty. As experience with POP increases beyond select referral center practices, further studies validating POP efficacy with long-term follow-up will help clarify when POP-guided intervention is most beneficial in relation to surgical intervention.

A case of spontaneous acute obstructive suppurative pancreatic ductitis associated with intraductal papillary mucinous neoplasms.

A 77-year-old woman was referred to our hospital due to left upper abdominal pain, appetite loss and body weight loss for 1 month. Her past medical history was diabetes and intraductal papillary mucinous neoplasms (IPMNs). She had no fever and physical examination revealed mild tenderness in the left upper abdomen. Blood tests showed elevated inflammatory response with normal serum pancreatic enzymes. Contrast-enhanced CT showed marked swelling of the pancreatic tail, increased peripancreatic fatty tissue density, multiple IPMNs and obscuration of the enlarged main pancreatic duct at the tail. EUS showed there was no obvious mass in the pancreas and protein plug was suspected in the main pancreatic duct. EUS-FNA was performed and pathology showed no malignancy. ERCP showed discharge of purulent pancreatic fluid from the major duodenal papilla and stenosis of the main pancreatic duct at the tail. The culture of the purulent pancreatic fluid revealed Streptococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa, leading to diagnosis of acute obstructive suppurative pancreatic ductitis (AOSPD). Endoscopic nasopancreatic drainage and antimicrobial treatment were started. The inflammatory response improved rapidly and the patient was discharged 30 days after admission. To our knowledge, this is the second reported case of spontaneous AOSPD associated with IPMNs.

Comparison with surgically resected mucinous cystic neoplasm of pancreas and branch-duct type intraductal papillary mucinous neoplasm considering clinico-radiological high-risk features: a reassessment of current guidelines.

PURPOSE: To perform a comparative analysis of surgically resected mucinous cystic neoplasm (MCN) of pancreas and branch-duct type intraductal papillary mucinous neoplasms (BD-IPMN) considering clinico-radiological high-risk predictors for malignant tumors using the current management guidelines. MATERIALS AND METHODS: 224 patients who underwent surgical resection and had histopathologically confirmed MCNs (benign 73; malignant 17) or BD-IPMNs (benign 110; malignant 24) and had pre-operative CT or MRI were retrospectively reviewed. Tumors classified as either high-grade dysplasia or invasive carcinoma were considered malignant, whereas those with low-grade dysplasia were considered benign. Imaging features were analyzed by two radiologists based on selected high-risk stigmata or worrisome features proposed by prevalent guidelines except tumors with main pancreatic duct dilatation (> 5 mm) were excluded. RESULTS: MCNs and BD-IPMNs showed significant differences in aspects like tumor size, location, the presence and size of enhancing mural nodules, the presence of wall or septal thickening, and multiplicity. Multivariate analyses revealed tumor size (OR, 1.336; 95% CI, 1.124-1.660, p = 0.002) and the presence of enhancing mural nodules (OR, 67.383; 95% CI, 4.490-1011.299, p = 0.002) as significant predictors of malignant MCNs. The optimal tumor size differentiating benign from malignant tumor was 8.95 cm, with a 70.6% sensitivity, 89% specificity, PPV of 27.6%, and NPV of 96.9%, demonstrating superior specificity than the guideline-suggested threshold of 4.0 cm. For malignant BD-IPMNs, the presence of enhancing mural nodules (OR, 15.804; 95% CI, 4.439-56.274, p < 0.001) and CA 19 - 9 elevation (OR, 19.089; 95%CI, 2.868-127.068, p = 0.002) as malignant predictors, with a size of enhancing mural nodule threshold of 5.5 mm providing the best malignancy differentiation. CONCLUSION: While current guidelines may be appropriate for managing BD-IPMNs, our results showed a notably larger optimal threshold size for malignant MCNs than that suggested by current guidelines. This warrants reconsidering existing guideline thresholds for initial risk stratification and management of MCNs.

Adjuvant chemotherapy for adenocarcinoma arising from intraductal papillary mucinous neoplasia: multicentre ADENO-IPMN study.

BACKGROUND: The clinical impact of adjuvant chemotherapy after resection for adenocarcinoma arising from intraductal papillary mucinous neoplasia is unclear. The aim of this study was to identify factors related to receipt of adjuvant chemotherapy and its impact on recurrence and survival. METHODS: This was a multicentre retrospective study of patients undergoing pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasia between January 2010 and December 2020 at 18 centres. Recurrence and survival outcomes for patients who did and did not receive adjuvant chemotherapy were compared using propensity score matching. RESULTS: Of 459 patients who underwent pancreatic resection, 275 (59.9%) received adjuvant chemotherapy (gemcitabine 51.3%, gemcitabine-capecitabine 21.8%, FOLFIRINOX 8.0%, other 18.9%). Median follow-up was 78 months. The overall recurrence rate was 45.5% and the median time to recurrence was 33 months. In univariable analysis in the matched cohort, adjuvant chemotherapy was not associated with reduced overall (P = 0.713), locoregional (P = 0.283) or systemic (P = 0.592) recurrence, disease-free survival (P = 0.284) or overall survival (P = 0.455). Adjuvant chemotherapy was not associated with reduced site-specific recurrence. In multivariable analysis, there was no association between adjuvant chemotherapy and overall recurrence (HR 0.89, 95% c.i. 0.57 to 1.40), disease-free survival (HR 0.86, 0.59 to 1.30) or overall survival (HR 0.77, 0.50 to 1.20). Adjuvant chemotherapy was not associated with reduced recurrence in any high-risk subgroup (for example, lymph node-positive, higher AJCC stage, poor differentiation). No particular chemotherapy regimen resulted in superior outcomes. CONCLUSION: Chemotherapy following resection of adenocarcinoma arising from intraductal papillary mucinous neoplasia does not appear to influence recurrence rates, recurrence patterns or survival.

CT findings and clinical effects of high grade pancreatic intraepithelial neoplasia in patients with intraductal papillary mucinous neoplasms.

PURPOSE: To investigate the common CT findings of high-grade (HG) PanIN and clinical effects in the remnant pancreas in patients with intraductal papillary mucinous neoplasm (IPMN) of the pancreas. MATERIALS AND METHODS: Two hundred fifty-one patients with surgically confirmed IPMNs (118 malignant [invasive carcinoma/high-grade dysplasia] and 133 benign [low-grade dysplasia]) were retrospectively enrolled. The grade of PanIN (233 absent/low-grade and 18 high-grade) was recorded, and all patients underwent serial CT follow-up before and after surgery. Two radiologists analyzed CT findings of high-risk stigmata or worrisome features according to 2017 international consensus guidelines. They also analyzed tumor recurrence on serial follow-up CT after surgery. Statistical analyses were performed to identify significant predictors and clinical impact on postoperative outcomes of HG PanIN. RESULTS: PanIN grade showed a significant association with IPMN grade (p = 0.012). Enhancing mural nodules ≥5 mm, abrupt main pancreatic duct (MPD) changes with distal pancreatic atrophy, increased mural nodule size and MPD diameter were common findings in HG PanIN (P<0.05). In multivariate analysis, abrupt MPD change with distal pancreatic atrophy (odds ratio (OR) 6.59, 95% CI: 2.32-18.72, <0.001) and mural nodule size (OR, 1.05; 95% CI, 1.02-1.08, 0.004) were important predictors for HG PanIN. During postoperative follow-up, HG PanIN (OR, 4.98; 95% CI, 1.22-20.33, 0.025) was significantly associated with cancer recurrence in the remnant pancreas. CONCLUSION: CT can be useful for predicting HG PanIN using common features, such as abrupt MPD changes and mural nodules. In HG PanIN, extra caution is needed to monitor postoperative recurrence during follow-up.