Contrast-enhanced EUS for the characterization of mural nodules within pancreatic cystic neoplasms: systematic review and meta-analysis

Endoscopic ultrasound-guided pancreatic duct drainage: a comprehensive state of the art review

INTRODUCTION

Endoscopic retrograde pancreatography (ERP) has traditionally been the standard modality for pancreatic endotherapy. However, in certain situations, failure of retrograde ductal access may warrant an alternative modality of drainage. This can occur in various settings like difficult and/or surgically altered anatomy or duodenal obstruction. Endoscopic ultrasound-guided pancreatic duct drainage (EUS-PDD) is a relatively newer addition to the armamentarium for endoscopic access to the PD.

AREAS COVERED

This comprehensive state-of-art review aims to give an overview of the indications, technical details, different approaches, and outcomes of EUS-PDD, with the latest evidence available in scientific literature.

EXPERT OPINION

Akin to its biliary drainage counterpart, EUS-PDD enables an EUS-assisted-ERP using rendezvous technique or EUS-guided drainage through transmural stenting. The technique has evolved over the ensuing years with multitude of accessories, approaches, and devices to optimize the outcomes. However, the technical success and adverse events rates need to be further improved. Additionally, it has a steep learning curve with requirements of advanced technical skill and optimum infrastructure back-up. Meticulous patient selection, precise knowledge of ductal anatomy, appropriate approach, and carefully chosen accessories can improve its clinical outcomes.

Pancreatic Ductal Adenocarcinoma (PDAC): A Review of Recent Advancements Enabled by Artificial Intelligence

Pancreatic Ductal Adenocarcinoma (PDAC) remains one of the most formidable challenges in oncology, characterized by its late detection and poor prognosis. Artificial intelligence (AI) and machine learning (ML) are emerging as pivotal tools in revolutionizing PDAC care across various dimensions. Consequently, many studies have focused on using AI to improve the standard of PDAC care. This review article attempts to consolidate the literature from the past five years to identify high-impact, novel, and meaningful studies focusing on their transformative potential in PDAC management. Our analysis spans a broad spectrum of applications, including but not limited to patient risk stratification, early detection, and prediction of treatment outcomes, thereby highlighting AI's potential role in enhancing the quality and precision of PDAC care. By categorizing the literature into discrete sections reflective of a patient's journey from screening and diagnosis through treatment and survivorship, this review offers a comprehensive examination of AI-driven methodologies in addressing the multifaceted challenges of PDAC. Each study is summarized by explaining the dataset, ML model, evaluation metrics, and impact the study has on improving PDAC-related outcomes. We also discuss prevailing obstacles and limitations inherent in the application of AI within the PDAC context, offering insightful perspectives on potential future directions and innovations.

Contrast-enhanced guided endoscopic ultrasound procedures

Contrast-enhanced endoscopic ultrasound (CH-EUS) can overcome the limitations of endoscopic ultrasound-guided acquisition by identifying microvessels inside inhomogeneous tumours and improving the characterization of these tumours. Despite the initial enthusiasm that oriented needle sampling under CH-EUS guidance could provide better diagnostic yield in pancreatic solid lesions, further studies did not confirm the supplementary values in cases of tissue acquisition guided by CH-EUS. This review details the knowledge based on the available data on contrast-guided procedures. The indications for CH-EUS tissue acquisition include isoechoic EUS lesions with poor visible delineation where CH-EUS can differentiate the lesion vascularisation from the surrounding parenchyma and also the mural nodules within biliopancreatic cystic lesions, which occur in select cases. Additionally, the roles of CH-EUS-guided therapy in patients whose pancreatic fluid collections or bile ducts that have an echogenic content have indications for drainage, and patients who have nonvisualized vessels that need to be highlighted via Doppler EUS are presented. Another indication is represented if there is a need for an immediate assessment of the post-radiofrequency ablation of pancreatic neuroendocrine tumours, in which case CH-EUS can be used to reveal the incomplete tumour destruction.

Basic Principles and Role of Endoscopic Ultrasound in Diagnosis and Differentiation of Pancreatic Cancer from Other Pancreatic Lesions: A Comprehensive Review of Endoscopic Ultrasound for Pancreatic Cancer

Pancreatic cancer is one of the leading causes of cancer-related deaths worldwide. Pancreatic lesions consist of both neoplastic and non-neoplastic lesions and often pose a diagnostic and therapeutic challenge due to similar clinical and radiological features. In recent years, pancreatic lesions have been discovered more frequently as incidental findings due to the increased utilization and widespread availability of abdominal cross-sectional imaging. Therefore, it becomes imperative to establish an early and appropriate diagnosis with meticulous differentiation in an attempt to balance unnecessary treatment of benign pancreatic lesions and missing the opportunity for early intervention in malignant lesions. Endoscopic ultrasound (EUS) has become an important diagnostic modality for the identification and risk stratification of pancreatic lesions due to its ability to provide detailed imaging and acquisition of tissue samples for analysis with the help of fine-needle aspiration/biopsy. The recent development of EUS-based technology, including contrast-enhanced endoscopic ultrasound, real-time elastography-endoscopic ultrasound, miniature probe ultrasound, confocal laser endomicroscopy, and the application of artificial intelligence has significantly augmented the diagnostic accuracy of EUS as it enables better evaluation of the number, location, dimension, wall thickness, and contents of these lesions. This article provides a comprehensive overview of the role of the different types of EUS available for the diagnosis and differentiation of pancreatic cancer from other pancreatic lesions while discussing their key strengths and important limitations.

Role of contrast-enhanced harmonic endoscopic ultrasonography (EUS) and EUS elastography in pancreatic lesions

Pancreatic cancers have a poor prognosis, and their incident rates have risen. Endoscopic ultrasonography (EUS) is an efficient and reliable diagnostic modality for pancreatic lesions, providing high spatial resolution. However, while EUS helps to detect minor pancreatic lesions, nearly all solid pancreatic lesions are hypoechoic, which creates difficulty in making differential diagnoses of pancreatic lesions. When diagnosing pancreatic lesions, the performance of image-enhanced EUS techniques is essential, such as EUS elastography or contrast-enhanced harmonic EUS (CH-EUS). CH-EUS diagnosis is based on assessing the vascularity of lesions, whereas tissue elasticity is measured via EUS elastography. Elastography is either strain or shear-wave, depending on the different mechanical properties being evaluated. The usefulness of enhanced EUS techniques is demonstrated in this review for the differential diagnosis of pancreatic lesions, including solid and cystic lesions, and pancreatic cancer staging.

Impact of preoperative endoscopic procedures on adverse event rates after surgical resection for main-duct and mixed-type intraductal papillary mucinous neoplasms (IPMNs)

BACKGROUND

Main-duct (MD-) and mixed-type (MT-) IPMNs harbor an increased risk of pancreatic cancer and warrant surgical resection. Preoperative endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) are important in the diagnosis of IPMNs. The aim of this study was to investigate whether endoscopic procedures manipulating the MD impact postoperative adverse events in patients with MD- and MT-IPMNs.

METHODS

We performed a retrospective study of 369 patients who underwent resections for MD- or MT-IPMN at two tertiary centers (2000-2019). Multivariable logistic regression analyses were performed for postoperative adverse events to compare the risks between intervention (ERCP, EUS-FNA with branch duct (BD) aspirated, EUS-FNA with MD aspirated from the duct directly or cyst/mass arising from MD) versus no-intervention group.

RESULTS

33.1 % of patients had a preoperative ERCP and 69.4 % had EUS-FNA. Postoperative adverse events included: 30-day readmission (12.7 %), delayed gastric emptying (13.8 %), pancreatic fistula (10.3 %), abdominal abscess (5.7 %), cardiopulmonary adverse events (11.4 %), and mortality (1.4 %). The model was adjusted for potential confounders. There were no significant differences between the ERCP and no-ERCP groups for specific adverse events. Compared to no-EUS-FNA groups, groups of EUS-FNA with BD aspiration and EUS-FNA with MD aspiration from the main pancreatic duct directly or cyst/mass arising from MD did not show a significant increase in specific adverse events.

CONCLUSIONS

Postoperative adverse events were not significantly increased among patients who had ERCP or EUS-FNA before surgical resection for MD- or MT-IPMNs. Endoscopic procedures directly sampling the MD can be safely pursued for diagnostic purposes in selected cases.

Protocol for a Multi-Center Confirmatory Trial to Evaluate the Differential Diagnostic Performance of Contrast-Enhanced Ultrasonography Using Perflubutane in Patients with a Pancreatic Mass: A Multicenter Prospective Study

For pancreatic masses, an evaluation of their vascularity using contrast-enhanced ultrasonography can help improve their characterization. This study was designed to evaluate the utility and safety of contrast-enhanced transabdominal ultrasonography (CE-TUS) and endoscopic ultrasonography (CE-EUS) in the diagnosis of pancreatic masses including solid or cystic masses. This multi-center comparative open-label superiority study is designed to compare Plain (P)-TUS/EUS alone with P-TUS/P-EUS plus CE-TUS/CE-EUS. Three hundred and one patients with a total of 232 solid pancreatic masses and 69 cystic masses were prospectively enrolled. The primary endpoints are to compare the diagnostic accuracy between P-TUS/P-EUS alone and P-TUS/P-EUS plus CE-TUS/CE-EUS for both the TUS and EUS of solid pancreatic masses, and to compare the diagnostic accuracy between P-EUS alone and P-EUS plus CE-EUS in cystic pancreatic masses. The secondary endpoints are to compare the diagnostic sensitivity and specificity of P-TUS/P-EUS alone and P-TUS/P-EUS plus CE-TUS/CE-EUS for pancreatic solid/cystic masses, and the accuracy of P-TUS alone and P-TUS plus CE-TUS for pancreatic cystic masses. Other secondary endpoints included comparing the diagnostic sensitivity, specificity, and accuracy of CE-TUS, CE-EUS and CE-computed tomography (CT) for solid/cystic pancreatic masses. The safety, degree of effective enhancement, and diagnostic confidence obtained with CE-TUS/CE-EUS will also be assessed.

Endoscopic ultrasound-guided radiofrequency ablation of pancreatic insulinoma: a state of the art review

INTRODUCTION

Insulinomas are the most common functional pancreatic neuroendocrine tumors (PNETs) that lead to incapacitating hypoglycemia. Guidelines recommend surgical resection as the mainstay of management. However, surgery is fraught with complications, causing significant peri/post-operative morbidity. Since insulinomas are usually benign, solitary, small (<2 cm), and do not need lymphadenectomy, hence, in this regard, endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is now being increasingly performed, to circumvent these adverse events and impairment of pancreatic function.

AREAS COVERED

A comprehensive literature search was undertaken across various databases (PubMed/MEDLINE, Embase, Scopus), with no language restriction, for relevant articles (case series, reviews, case reports) pertaining to EUS-RFA for insulinoma and PNETs, till October 2023. In this review, we have explicated the role of EUS-RFA for insulinoma management, detailing thoroughly its mechanism of action, EUS-RFA devices with data on its safety and efficacy, and an algorithmic approach for its management.

EXPERT OPINION

EUS-RFA is being advocated as a 'mini-invasive' option with the potential to replace surgery as a first-line approach for benign, sporadic, solitary, and small (<2 cm) insulinomas. Under real-time guidance, EUS-RFA has immense precision, is safe, predictable, with acceptable safety profile. Presently, it is being frequently performed for high-risk or inoperable candidates. Current need-of-the-hour is a randomized controlled trial to substantiate its role in the therapeutic algorithm for insulinoma management.

Predictive models in EUS/ERCP

Predictive models (PMs) in endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) have the potential to improve patient outcomes, enhance diagnostic accuracy, and guide therapeutic interventions. This review aims to summarize the current state of predictive models in ERCP and EUS and their clinical implications. To be considered useful in clinical practice a PM should be accurate, easy to perform, and may consider objective variables. PMs in ERCP estimate correct indication, probability of success, and the risk of developing adverse events. These models incorporate patient-related factors and technical aspects of the procedure. In the field of EUS, these models utilize clinical and imaging data to predict the likelihood of malignancy, presence of specific lesions, or risk of complications related to therapeutic interventions. Further research, validation, and refinement are necessary to maximize the utility and impact of these models in routine clinical practice.

Sequential high-intensity focused ultrasound treatment combined with chemotherapy for inoperable pancreatic cancer: a retrospective analysis for prognostic factors and survival outcomes

OBJECTIVE

To evaluate the effect of HIFU (High-Intensity Focused Ultrasound) therapy on the survival and prognosis of patients with inoperable pancreatic cancer, and the clinical application of serological prognostic indicators.

METHODS

We retrospectively analyzed the clinicopathological features, laboratory tests and follow-ups of 192 patients. Among the patients, 57 were treated with HIFU prior to chemotherapy (HIFU-priority), and 135 patients received chemotherapy followed by HIFU (HIFU-second). Univariate and multivariate Cox regression analysis was used to determine the prognostic value of tumor inflammation-related serological markers. A nomogram model was established based on the identified prognostic factors.

RESULTS

Univariate analysis showed that receiving the treatment regimen in HIFU-priority was a significant protective factor for overall survival (OS, p < 0.001). Tumor stage, high C-reactive protein (CRP), high gamma-glutamyl transferase(γGT) high carbohydrate antigen 125 (CA125), high neutrophil-to-lymphocyte ratio (NLR), high lymphocyte-to-monocyte ratio (LMR) and liver metastasis were significant risk factors for poor prognosis (p < 0.05). CRP combined with normal tumor marker CA125 (CRP + CA125) was associated with longer OS (p = 0.005). Multivariate analysis shows that HIFU-priority is a protective factor for OS (Hazard Ratio, HR: 0.38; 95% confidence interval(CI): 0.25-0.57), tumor stage (HR: 1.61; 95% CI: 1.12-2.31), CRP + CA125 (HR: 1.46; 95% CI: 1.02-2.08) and γGT (HR: 1.44; 95% CI: 1.04-1.98) are risk factors for OS and serve as independent prognostic factors in the nomogram.

CONCLUSION

Early application of HIFU treatment improves the OS of patients with inoperable pancreatic cancer. CRP + CA125 and γGT are independent prognostic factors.

Intraoperative pancreatoscopy can improve the detection of skip lesions during surgery for intraductal papillary mucinous neoplasia: A pilot study

OBJECTIVES

Intraoperative pancreatoscopy is a promising procedure that might guide surgical resection for suspected main duct (MD) and mixed type (MT) intraductal papillary mucinous neoplasms (IPMNs). The aim of the present study was to assess the diagnostic yield and clinical impact of intraoperative pancreatoscopy in patients operated on for MD and MT-IPMNs.

METHODS

This is a retrospective cohort study. Patients undergoing surgery for suspected MD or MT-IPMN underwent intraoperative pancreatoscopy and frozen section analysis. In all patients who required extended resection due to pancreatoscopic findings, we compared the final histology with the results of the intraoperative frozen section analysis.

RESULTS

In total, 46 patients, 48% females, mean age (range) 67 years (45-82 years) underwent intraoperative pancreatoscopy. No mortality or procedure related complications were observed. Pancreatoscopy changed the operative course in 30 patients (65%), leading to extended resections in 20 patients (43%) and to parenchyma sparing procedures in 10 patients (22%). Analyzing the group of patients who underwent extended resections, 7 (35%) displayed lesions that needed further surgical treatment (six high grade dysplasia and one with G1 pancreatic neuroendocrine tumor) and among those 7, just 1 (14%) would have been detected exclusively with histological frozen section analysis of the transection margin. The combination of both pancreatoscopy and frozen section analysis lead to 86% sensitivity and 92% specificity for the detection of pathological tissue in the remnant pancreas.

CONCLUSION

Intraoperative pancreatoscopy is a safe and feasible procedure and might allow the detection of skip lesions during surgery for suspect MD-involving IPMNs.

Study protocol for a multicenter randomized controlled trial to compare radiofrequency ablation with surgical resection for treatment of pancreatic insulinoma

BACKGROUND

Insulinoma is the most common functional pancreatic neuroendocrine tumor and treatment is required to address symptoms associated with insulin hypersecretion. Surgical resection is effective but burdened by high rate of adverse events (AEs). Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) demonstrated encouraging results in terms of safety and efficacy for the management of these tumors. However, studies comparing surgery and EUS-RFA are lacking.

AIMS

The primary aim is to compare EUS-RFA with surgery in term of safety (overall rate of AEs). Secondary endpoints include: (a) severe AEs rate; (b) clinical effectiveness; (c) patient's quality of life; (d) length of hospital stay; (e) rate of local/distance recurrence; (f) need of reintervention; (g) rate of endocrine and exocrine pancreatic insufficiency; (h) factors associated with EUS-RFA related AEs and clinical effectiveness.

METHODS

ERASIN-RCT is an international randomized superiority ongoing trial in four countries. Sixty patients will be randomized in two arms (EUS-RFA vs surgery) and outcomes compared. Two EUS-RFA sessions will be allowed to achieve symptoms resolution. Randomization and data collection will be performed online.

DISCUSSION

This study will ascertain if EUS-RFA can become the first-line therapy for management of small, sporadic, pancreatic insulinoma and be included in a step-up approach in case of clinical failure.

Risk factors for EUS-guided radiofrequency ablation adverse events in patients with pancreatic neoplasms: a large national French study (RAFPAN study)

BACKGROUND AND AIMS

EUS-guided radiofrequency ablation (EUS-RFA) has been described as a potentially curative option for solid and cystic pancreatic neoplasms. We aimed to assess the safety and efficacy of pancreatic EUS-RFA in a large study population.

METHODS

A retrospective study retrieving all consecutive patients who underwent pancreatic EUS-RFA during 2019 and 2020 in France was conducted. Indication, procedural characteristics, early and late adverse events (AEs), and clinical outcomes were recorded. Risk factors for AEs and factors related to complete tumor ablation were assessed on univariate and multivariate analyses.

RESULTS

One hundred patients (54% men, 64.8 ± 17.6 years old) affected by 104 neoplasms were included. Sixty-four neoplasms were neuroendocrine neoplasms (NENs), 23 were metastases, and 10 were intraductal papillary mucinous neoplasms with mural nodules. No procedure-related mortality was observed, and 22 AEs were reported. Proximity of pancreatic neoplasms (≤1 mm) to the main pancreatic duct was the only independent risk factor for AEs (odds ratio [OR), 4.10; 95% confidence interval [CI), 1.02-15.22; P = .04). Fifty-nine patients (60.2%) achieved a complete tumor response, 31 (31.6%) a partial response, and 9 (9.2%) achieved no response. On multivariate analysis, NENs (OR, 7.95; 95% CI, 1.66-51.79; P < .001) and neoplasm size <20 mm (OR, 5.26; 95% CI, 2.17-14.29; P < .001) were independently related to complete tumor ablation.

CONCLUSIONS

The results of this large study confirm an overall acceptable safety profile for pancreatic EUS-RFA. Close proximity (≤1 mm) to the main pancreatic duct represents an independent risk factor for AEs. Good clinical outcomes in terms of tumor ablation were observed, especially for small NENs.

Intraductal papillary mucinous neoplasm of the biliary tract in the caudate lobe of the liver: a case report and literature review

An intraductal papillary mucinous neoplasm of the biliary tract (BT-IPMN) in the caudate lobe of the liver is a rare tumor originating from the bile duct. Approximately 40% of the intraductal papillary neoplasms of the biliary tract (IPNB) secrete mucus and can grow in the intrahepatic or extrahepatic bile ducts. A 65-year-old woman presented with recurrent episodes of right upper pain. She developed her first episode 8 years ago, which resolved spontaneously. The frequency of symptoms has increased in the last 2 years. She underwent laparoscopic hepatectomy and choledochal exploration and was pathologically diagnosed with a rare BT-IPMN of the caudate lobe after admission. Here, we review studies on IPNB cases and systematically describe the pathological type, diagnosis, and treatment of IPNB to provide a valuable reference for hepatobiliary surgeons in the diagnosis and treatment of this disease.

Surveillance of Pancreatic Cystic Neoplasms

Pancreatic cystic neoplasms (PCNs) are increasingly detected because of the widespread use of cross-sectional imaging and overall aging population. While the majority of these cysts are benign, some can progress to advanced neoplasia (defined as high-grade dysplasia and invasive cancer). As the only widely accepted treatment for PCNs with advanced neoplasia is surgical resection, accurate preoperative diagnosis, and stratification of malignant potential for deciding about surgery, surveillance or doing nothing remains a clinical challenge. Surveillance strategies for pancreatic cysts (PCNs) combine clinical evaluation and imaging to assess changes in cyst morphology and symptoms that may indicate advanced neoplasia. PCN surveillance heavily relies on various consensus clinical guidelines that focus on high-risk morphology, surgical indications, and surveillance intervals and modalities. This review will focus on current concepts in the surveillance of newly diagnosed PCNs, especially on low-risk presumed intraductal papillary mucinous neoplasms (those without worrisome features and high-risk stigmata), and appraise current clinical surveillance guidelines.

Risk Models for Pancreatic Cyst Diagnosis

The overall prevalence of pancreatic cysts (PCs) is high in the general population. In clinical practice PCs are often incidentally discovered and are classified into benign, premalignant, and malignant lesions according to the World Health Organization. For this reason, in the absence of reliable biomarkers, to date clinical decision-making relies mostly on risk models based on morphological features. The aim of this narrative review is to present the current knowledge regarding PC's morphologic features with related estimated risk of malignancy and discuss available diagnostic tools to minimize clinically relevant diagnostic errors.

The spearfishing sign: differentiating mucin from mural nodules in pancreatic cysts

Video 1EUS evaluation of intracystic mucin and demonstration of spearfishing sign.

Using Endoscopy in the Diagnosis of Pancreato-Biliary Cancers

Pancreatic cancer and cholangiocarcinoma are life threatening oncological conditions with poor prognosis and outcome. Pancreatic cystic lesions are considered precursors of pancreatic cancer as some of them have the potential to progress to malignancy. Therefore, accurate identification and classification of these lesions is important to prevent the development of invasive cancer. In the biliary tract, the accurate characterization of biliary strictures is essential for providing appropriate management and avoiding unnecessary surgery. Techniques have been developed to improve the diagnosis, risk stratification, and management of pancreato-biliary lesions. Endoscopic ultrasound (EUS) and associated techniques, such as elastography, contrasted-enhanced EUS, and EUS-guided needle confocal laser endomicroscopy, may improve diagnostic accuracy. In addition, intraductal techniques applied during endoscopic retrograde cholangiopancreatography (ERCP), such as new generation cholangioscopy and in vivo cellular evaluation through probe-based confocal laser endomicroscopy, can increase the diagnostic yield in characterizing indeterminate biliary strictures. Both EUS-guided and intraductal approaches can provide the possibility for tissue sampling with new tools, such as needles, biopsies forceps, and brushes. At the molecular level, novel biomarkers have been explored that provide new insights into diagnosis, risk stratification, and management of these lesions.

Pancreatico-gastric fistula arising from IPMN associated with ductal adenocarcinoma of the pancreas: a case report and a literature review

Introduction

An intraductal papillary mucinous neoplasm (IPMN) is a potentially malignant cystic tumor that is characterized by an excessive papillary proliferation of mucin-producing epithelial cells. The IPMN usually exhibits different degrees of dysplasia and is accompanied by cystic dilation of the main pancreatic duct (MPD) or side branch. We report a case of an IPMN that has penetrated the stomach and has differentiated into an adenocarcinoma.

Case presentation

A 69-year-old female, suffering from chronic pancreatitis of unknown etiology, visited our outpatient clinic with complaints of sudden weight loss, diarrhea, and abdominal pain. She underwent several examinations to evaluate the reasons for her sudden onset of symptoms. A gastroscopy showed an ulcerated lesion covered with mucus. CT and magnetic resonance cholangiopancreatography images revealed that the MPD was dilated to 1.3 cm with a fistula formation between the MPD and the stomach. After a multidisciplinary discussion of this case, a total pancreatectomy was proposed. An en bloc total pancreatectomy with gastric wedge resection including the fistula together with splenectomy was carried out. A Roux-en-Y choledochojejunostomy and gastrojejunostomy were performed. Histology results revealed the association of IPMN with invasive carcinoma.

Discussion

Many reports on IPMN of the pancreas have been published recently. Fistula formation between IPMN and adjacent organs is possible. Given the CT and endoscopic ultrasonography findings, it shows that in our case a main duct IPMN (MD-IPMN) formed a pancreatico-gastric fistula. We point out that the adherence of invasive cancer cells contributed to the fistula formation between the pancreas and the stomach.

Conclusion

This case report provides evidence for the possibility of IPMN becoming complicated with pancreatico-gastric fistula. Thus, we suggest that surgical resection should be considered in the case of MD-IPMN because of its high propensity for malignant transformation.

Recent Developments in the Field of Endoscopic Ultrasound for Diagnosis, Staging, and Treatment of Pancreatic Lesions

Endoscopic ultrasound (EUS) plays a crucial role in the diagnosis of both solid and cystic pancreatic lesions and in the staging of patients with pancreatic cancer through its use for tissue and fluid sampling. Additionally, in cases of precancerous lesions, EUS-guided therapy can also be provided. This review aims to describe the most recent developments regarding the role of EUS in the diagnosis and staging of pancreatic lesions. Moreover, complementary EUS imaging modalities, the role of artificial intelligence, new devices, and modalities for tissue acquisition, and techniques for EUS-guided treatment are discussed.

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 mm^2,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.

Diabetes in intraductal papillary mucinous neoplasm of the pancreas and its association with malignancy

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) have the potential to become malignant. Few studies have focused on the prevalence of the diabetes mellitus (DM) in IPMNs and its association with malignancy. We evaluated the association between DM and malignant IPMNs in this study.

METHODS

A total of 226 patients with pathologically confirmed IPMNs were included. Demographic data, serum biochemical data, and imaging findings were collected. The malignant IPMNs were defined as those with high-grade dysplasia and associated invasive carcinoma. The association between DM and malignant IPMNs was studied using logistic regression analysis.

RESULTS

The prevalence of DM was 17.7% for all type IPMNs and 31.7% for malignant IPMNs. Compared to patients without DM, those with DM had a 3.6-fold (odds ratio [OR]: 3.62; 95% confidence interval [CI]: 1.26-10.44) higher risk of invasive carcinoma and 2.5-fold (OR: 2.48; 95% CI: 1.06-5.77) higher risk of malignant IPMNs. Similar results were observed in main pancreatic duct (MPD) involved IPMNs. New-onset DM was associated with a 4.13-fold (OR: 4.13, 95% CI: 1.27-13.36) higher risk of invasive carcinoma.

CONCLUSION

DM is associated with a higher risk of malignant IPMNs and invasive carcinoma, especially in patients with MPD-involved IPMNs.

Endoscopic Ultrasound Advanced Techniques for Diagnosis of Gastrointestinal Stromal Tumours

Gastrointestinal Stromal Tumors (GISTs) are subepithelial lesions (SELs) that commonly develop in the gastrointestinal tract. GISTs, unlike other SELs, can exhibit malignant behavior, so differential diagnosis is critical to the decision-making process. Endoscopic ultrasound (EUS) is considered the most accurate imaging method for diagnosing and differentiating SELs in the gastrointestinal tract by assessing the lesions precisely and evaluating their malignant risk. Due to their overlapping imaging characteristics, endosonographers may have difficulty distinguishing GISTs from other SELs using conventional EUS alone, and the collection of tissue samples from these lesions may be technically challenging. Even though it appears to be less effective in the case of smaller lesions, histology is now the gold standard for achieving a final diagnosis and avoiding unnecessary and invasive treatment for benign SELs. The use of enhanced EUS modalities and elastography has improved the diagnostic ability of EUS. Furthermore, recent advancements in artificial intelligence systems that use EUS images have allowed them to distinguish GISTs from other SELs, thereby improving their diagnostic accuracy.

Role of Endoscopic Ultrasound in the Evaluation of Pancreatic Cystic Neoplasms: A Concise Review

Pancreatic cystic lesions are being discovered as incidental lesions during cross-sectional imaging studies of the abdomen with increasing frequency. Endoscopic ultrasound is an important diagnostic modality for managing pancreatic cystic lesions. There are various types of pancreatic cystic lesions, from benign to malignant. Endoscopic ultrasound has a multifactorial role in delineating the morphology of pancreatic cystic lesions, ranging from fluid and tissue acquisition for analysis-fine needle aspiration and through-the-needle biopsy, respectively-to advanced imaging techniques, such as contrast-harmonic mode endoscopic ultrasound and EUS-guided needle-based confocal laser endomicroscopy. In this review, we will summarize and provide an update on the specific role of EUS in the management of pancreatic cystic lesions.

Diagnosis and Management of Pancreatic Cysts: A Comprehensive Review of the Literature

The prevalence of pancreatic cysts has been rising due to the widespread use of cross-sectional imaging (CT scan and MRI) of the abdomen. While most pancreatic cysts are benign and do not require treatment or surveillance, a significant minority are premalignant and rarely malignant. The risk stratification of these lesions is not straightforward, and individual risk assessment, cyst size, distribution, and alarming morphologic features (when present) can guide the next steps in management. Neoplastic pancreatic cysts are mucinous or non-mucinous. Endoscopic ultrasound with fine-needle aspiration is often required to classify pancreatic cysts into mucinous and non-mucinous cysts and to assess the malignant potential. Advances in endoscopic techniques (confocal laser endomicroscopy, microforceps biopsy) can provide a definitive diagnosis of pancreatic cysts in some cases; however, the use of these techniques involves a higher risk of adverse events.

Comparative Performance of Endoscopic Ultrasound-Based Techniques in Patients With Pancreatic Cystic Lesions: A Network Meta-Analysis

INTRODUCTION

Evidence on the comparative diagnostic performance of endoscopic ultrasound (EUS)-based techniques for pancreatic cystic lesions (PCLs) is limited. This network meta-analysis comprehensively compared EUS-based techniques for PCL diagnosis.

METHODS

A comprehensive literature search was performed for all comparative studies assessing the accuracy of 2 or more modalities for PCL diagnosis. The primary outcome was the diagnostic efficacy for mucinous PCLs. Secondary outcomes were the diagnostic efficacy for malignant PCLs, diagnostic success rate, and adverse event rate. A network meta-analysis was conducted using the ANOVA model to assess the diagnostic accuracy of each index.

RESULTS

Forty studies comprising 3,641 patients were identified. The network ranking of the superiority index for EUS-guided needle-based confocal laser endomicroscopy (EUS-nCLE) and EUS-guided through-the-needle biopsy (EUS-TTNB) were significantly higher than other techniques for differentiating mucinous PCLs; besides, EUS-TTNB was also the optimal technique in identifying malignant PCLs. The evidence was inadequate for EUS-nCLE diagnosing malignant PCLs and contrast-enhanced harmonic EUS diagnosing both mucinous and malignant PCLs. Glucose showed a high sensitivity but low specificity, and molecular analysis (KRAS, GNAS, and KRAS + GNAS mutations) showed a high specificity but low sensitivity for diagnosing mucinous PCLs. Satisfactory results were not obtained during the evaluation of the efficiency of pancreatic cyst fluid (PCF) biomarkers in detecting malignant PCLs.

DISCUSSION

For centers with relevant expertise and facilities, EUS-TTNB and EUS-nCLE were better choices for the diagnosis of PCLs. Further studies are urgently required for further improving PCF biomarkers and validating the diagnostic performance of the index techniques.

Diagnostic, Structured Classification and Therapeutic Approach in Cystic Pancreatic Lesions: Systematic Findings with Regard to the European Guidelines

Due to the increasing use of cross-sectional imaging techniques and new technical possibilities, the number of incidentally detected cystic lesions of the pancreas is rapidly increasing in everyday radiological routines. Precise and rapid classification, including targeted therapeutic considerations, is of essential importance. The new European guideline should also support this. This review article provides information on the spectrum of cystic pancreatic lesions, their appearance, and a comparison of morphologic and histologic characteristics. This is done in the context of current literature and clinical value. The recommendations of the European guidelines include statements on conservative management as well as relative and absolute indications for surgery in cystic lesions of the pancreas. The guidelines suggest surgical resection for mucinous cystic neoplasm (MCN) ≥ 40 mm; furthermore, for symptomatic MCN or imaging signs of malignancy, this is recommended independent of its size (grade IB recommendation). For main duct IPMNs (intraductal papillary mucinous neoplasms), surgical therapy is always recommended; for branch duct IPMNs, a number of different risk criteria are applicable to evaluate absolute or relative indications for surgery. Based on imaging characteristics of the most common cystic pancreatic lesions, a precise diagnostic classification of the tumor, as well as guidance for further treatment, is possible through radiology.

A model for predicting degree of malignancy in patients with intraductal papillary mucinous neoplasm

Background/Objectives

There is no predictive model available to address early stage malignant intraductal papillary mucinous neoplasm (IPMN) including high grade dysplasia (HGD) and pT1a (invasive component≤0.5 cm). The aim of this study was to establish an objective and sufficient model to predict the degree of malignancy in patients with IPMN, which can be easily applied in daily practice and adopted for any type of lesion.

Methods

A retrospective cohort study of 309 patients who underwent surgical resection for IPMN was performed. Members of the cohort were randomly allocated to the training or testing set. A detection tree model and random forest model were used for a 3-class classification to distinguish low grade dysplasia (LGD), HGD/pT1a IPMN, and invasive intraductal papillary mucinous cancer (I-IPMC) beyond pT1a.

Results

Of the 309 patients, 54 (17.4%) had early stage malignancy (19 HGD, 35 pT1a), 49 (15.9%) had I-IPMC beyond pT1a, and 206 (66.7%) had LGD IPMN. We proposed a 3-class classification model using a random forest algorithm, and the model had an accuracy of 99.5% with the training set, and displayed an accuracy of 96.0% with the testing set. We used SHAP for interpretation of the model and showed the top five factors (mural nodule size, main pancreatic duct diameter, CA19-9 levels, lesion edge and common bile duct dilation) were most likely to influence the 3-class classification results in terms of interpretation of the random forest model.

Conclusions

This predictive model will help assess an individual's risk for different stages of IPMN malignancy and may help identify patients with IPMN who require surgery.

A Review of Endoscopic Ultrasound-Guided Chemoablative Techniques for Pancreatic Cystic Lesions

Pancreatic cystic lesions (PCLs) are known precursors to pancreatic cancer, one of the deadliest types of cancer worldwide. Surgical removal or pancreatectomies remain the central approach to managing precancerous high-risk PCLs. Endoscopic ultrasound (EUS)-guided therapeutic management of PCLs is a novel management strategy for patients with prohibitive surgical risks. Various ablation techniques have been explored in previous studies utilizing EUS-guided fine needle injection (FNI) of alcohol and chemotherapeutic agents. This review article focuses on EUS-FNI and chemoablation, encompassing the evolution of chemoablation, pancreatic cyst selection, chemotherapy drug selection, including novel agents, and a discussion of its safety and efficacy.

Comparison of Clinical and Imaginal Features According to the Pathological Grades of Dysplasia in Branch-Duct Intraductal Papillary Mucinous Neoplasm (BD-IPMN) for Personalized Medicine

Background: In patients with BD-IPMN, surgical indications have been focused on finding malignant lesions (HGD, high-grade dysplasia/IC, invasive carcinoma). The aim of this study was to compare the preoperative factors that distinguish HGD from LGD (low-grade dysplasia) and HGD from IC to find the optimal pathologic target for surgery according to individuals, considering surgical risks and outcomes. Methods: We retrospectively analyzed 232 patients with BD-IPMN diagnosed based on pathology after surgery and preoperative images. The primary outcome was identifying preoperative factors distinguishing HGD from LGD, and HGD from IC. Results: In patients with LGD/HGD, a solid component or an enhancing mural nodule ≥ 5 mm (OR = 9.29; 95% CI: 3.3−54.12; p < 0.000) and thickened/enhancing cyst walls (OR = 6.95; 95% CI: 1.68−33.13; p = 0.008) were associated with HGD. In patients with malignant lesions (HGD/IC), increased serum CA 19-9 (OR = 12.59; 95% CI: 1.81−87.44; p = 0.006) was associated with IC. Conclusions: The predictive factors for HGD were the presence of a solid component or an enhancing mural nodule ≥ 5 mm and thickened/enhancing cyst walls compared with LGD, and if accompanied by increased CA 19-9, it might be necessary to urgently evaluate the lesion due to the possibility of progression to IC. Based on this finding, we need to find HGD as the optimal pathologic target for surgery to improve survival in low-surgical-risk patients, and IC could be assumed to be the optimal pathologic target for surgery in high-surgical-risk patients because of high morbidity and mortality associated with surgery.

Endoscopic ultrasonography: Enhancing diagnostic accuracy

Endoscopic ultrasound (EUS) is an essential technique for the management of several diseases. Over the years, new technologies have been developed because to improve and overcome certain limitations related to EUS guided tissue acquisition. Among these new methods, EUS guided elastography and contrast enhanced EUS has arisen as the most widely recognized and available. We will review in this manuscript the different techniques of elastography and contrast enhancement. Nowadays, there are well establish indications for advance imaging, mainly for supporting the management of pancreatic diseases (diagnosis of chronic pancreatitis and differential diagnosis of solid and cystic pancreatic tumors) and characterization of lymph nodes. However, there are more data on new potential indications for the near future.

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02577-3.

Long-term outcomes of patients with multifocal intraductal papillary mucinous neoplasm following pancreatectomy

BACKGROUND

The decision to perform surgery is complicated by the presence of multifocal (MF) intraductal papillary mucinous neoplasms (IPMNs), which are characterized by two or more cysts located in different areas of the pancreas.

OBJECTIVES

We aimed to establish a suitable treatment strategy and surgical indications in patients with MF-IPMNs.

METHODS

This single-center retrospective study included patients with IPMNs who underwent pancreatic resection from 2006 to 2020. Patients with distant metastasis and patients with IPMNs of the main pancreatic duct were excluded from the analysis.

RESULTS

After excluding 22 patients, 194 patients were included. One hundred thirteen patients (58.2%) had unifocal IPMNs, while 81 patients (41.8%) had MF-IPMNs. There were no significant differences in the 5-year disease-specific survival (DSS) rate (92.3% vs. 92.4%, p = 0.976) and the 5-year disease-free survival rate (88.6% vs. 86.5%, p = 0.461). The multivariate analysis identified high-risk stigmata, invasive carcinoma, and lymph node metastasis as independent predictors of DSS. The presence of cystic lesions in the pancreatic remnant was not a predictor of survival. Even in the MF-IPMN group, there were no significant differences in DSS when stratified by procedure (total pancreatectomy vs. segmental pancreatectomy, p = 0.268) or presence of cystic lesions in the pancreatic remnant (p = 0.476). The multivariate analysis identified lymph node metastasis as an independent predictor of DSS in the MF-IPMN group.

CONCLUSIONS

In patients with MF-IPMNs, each cyst should be evaluated individually for the presence of features associated with malignancy.

Contrast-enhanced ultrasound of solid pancreatic head lesions: a prospective study

OBJECTIVE

To evaluate the role of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of solid pancreatic head lesions (SPHL).

METHODS

This prospective study comprised consecutive patients with SPHL who underwent CEUS evaluation of the pancreas. Findings recorded at CEUS were enhancement patterns (degree, completeness, centripetal enhancement, and percentage enhancement) and presence of central vessels. In addition, time to peak (TTP) and washout time (WT) were recorded. The final diagnosis was based on histopathology or cytology. Multivariate analysis was performed to identify parameters that were significantly associated with pancreatic ductal adenocarcinoma (PDAC).

RESULTS

Ninety-eight patients (median age 53.8 years, 59 males) were evaluated. The final diagnosis was PDAC (n = 64, 65.3%), inflammatory mass (n = 16, 16.3%), neuroendocrine tumor (NET, n = 14, 14.3%), and other tumors (n = 4, 4.1%). Hypoenhancement, incomplete enhancement, and centripetal enhancement were significantly more common in PDAC than non-PDAC lesions (p = 0.001, p = 0.031, and p = 0.002, respectively). Central vessels were present in a significantly greater number of non-PDAC lesions (p = 0.0001). Hypoenhancement with < 30% enhancement at CEUS had sensitivity and specificity of 80.6% and 67.7%, respectively, for PDAC. There was no significant difference in the TTP and WT between PDAC and non - PDAC lesions. However, the WT was significantly shorter in PDAC compared to NET (p = 0.011). In multivariate analysis, lack of central vessels was significantly associated with a PDAC diagnosis.

CONCLUSION

CEUS is a useful tool for the evaluation of SPHL. CEUS can be incorporated into the diagnostic algorithm to differentiate PDAC from non-PDAC lesions.

KEY POINTS

• Hypoenhancement and incomplete enhancement at CEUS were significantly more common in PDAC than in non-PDAC. • Central vessels at CEUS were significantly associated with PDAC. • There was no difference in TTP and WT between PDAC and non-PDAC lesions.

Clinical Utility of the Contrast-Enhanced Endoscopic Ultrasound Guided Fine Needle Aspiration in the Diagnosis of Pancreatic Cyst

Endoscopic ultrasound fine needle aspiration (EUS-FNA) cytology from an intracystic fluid is useful in the differentiation of pancreatic cysts, with low sensitivity, which increases when the solid component is targeted. The clinical utility of contrast-enhanced guided EUS-FNA (CH-EUS-FNA) in the solid component is not known. We aimed to assess the diagnostic value of CH-EUS-FNA in enhanced mural nodules and discrimination between different cysts using contrast-enhanced endoscopic ultrasound (CH-EUS). The prospective study recruited patients with pancreatic cysts with an unclear diagnosis. The CH-EUS was followed by CH-EUS-FNA. The final diagnosis was based on surgery or the correlation between clinical history, cross-sectional imaging, echoendoscopic morphology, cystic fluid analysis, and follow-up. Fifty-eight patients with pancreatic cysts were evaluated. The mucinous cysts had wall arterial enhancement more often than non- mucinous cysts (p < 0.0001), with 90.2% sensitivity and 70.6% specificity. The CH-EUS-FNA from cystic fluid and mural nodules identified mucinous cysts and malignancy with 82.4% and 84.2% sensitivity and 92% and 100% specificity. Twenty-one cysts had solid components, but only 13 were enhanced mural nodules on EUS assessment with conclusive cytology in all cases and malignancy in 76.9%. Contrast-enhanced endoscopic ultrasound should be completed in all PCN with solid components in order to avoid unnecessary EUS-FNA and to guide FNA for the identification of malignant cysts.

Diagnostic Dilemma of Biliopancreatic Contrast-Enhanced Harmonic Endoscopic Ultrasonography

Background: The utility of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) alone in the biliopancreatic region appears to be limited because it is highly dependent on the experience and skill of the endoscopist. Therefore, the present study aimed to validate the efficacy of CH-EUS in clinical practice. Methods: Between January 2018 and March 2019, 301 consecutive patients who underwent CH-EUS were prospectively enrolled in this study. The diagnostic performance of CH-EUS was compared with that of dynamic computed tomography (CT), magnetic resonance imaging (MRI), and all combinations (i.e., CH-EUS, dynamic CT, and MRI) using a Bonferroni correction. A multiple logistic regression analysis was performed to extract each disease that allowed the CH-EUS diagnosis to be consistent with the final diagnosis. Results: In multiple comparisons of diagnostic performance, no significant differences were observed among dynamic CT, MRI, and CH-EUS (p = 1.00), but the diagnostic performance was significantly higher when all modalities were combined (p < 0.001). Moreover, only intraductal papillary mucinous neoplasm comprising adenoma or carcinoma (IPMN, n = 161) showed significance with respect to the agreement with the final diagnosis (p = 0.006). Conclusions: Our results showed that CH-EUS-based diagnosis of IPMN may be possible in clinical practice. On the contrary, to accurately diagnose biliopancreatic diseases other than IPMN, comprehensive diagnosis using multiple modalities may be necessary, rather than relying on CH-EUS alone.

MRI-Based Pancreatic Atrophy Is Associated With Malignancy or Invasive Carcinoma in Intraductal Papillary Mucinous Neoplasm

Background

Abrupt change in the caliber of the main pancreatic duct (MPD) with distal pancreatic atrophy (PA) was considered as one of worrisome features in the International Association of Pancreatology guideline and American College of Gastroenterology guideline for the management of intraductal papillary mucinous neoplasms (IPMNs). However, this feature was not included in other guidelines. Moreover, the association between PA alone and malignancy in IPMNs has not been fully evaluated. In the present study, we investigated the role of image-based PA in identifying malignant IPMNs or invasive carcinoma.

Methods

A total of 186 patients with IPMNs were included for analysis. The tumor size, location, MPD diameter, presence of a mural nodule (MN), and PA were evaluated using magnetic resonance imaging. Demographic information and serum carbohydrate antigen 19-9 and carcinoembryonic antigen (CEA) levels were also collected. IPMNs with high-grade dysplasia and associated invasive carcinoma were regarded as malignant IPMNs.

Results

PA was observed in 34 cases (18.3%). The occurrence of malignant IPMNs or invasive carcinoma in patients with PA were significantly higher than in those without PA (52.9% vs. 22.3%; 44.1% vs. 8.9%, all P < 0.01). Multivariate logistic regression analysis showed that PA was an independently associated factor for malignant IPMNs [odds ratio (OR) = 2.69, 95% confidence interval (CI): 1.07-6.78] or invasive carcinoma (OR = 7.78, 95%CI: 2.62-23.10) after modified with confounders. Subgroup analysis in MPD-involved IPMNs also indicated that PA was an independently associated factor for invasive carcinoma (OR = 9.72, 95%CI: 2.43-38.88). PA had a similar performance with MPD plus MN [the area under the curve (AUC) was both 0.71] in identifying malignancy. PA had a higher performance in identifying invasive carcinoma in MPD-involved IPMNs than MN (AUC = 0.71 vs. 0.65, P = 0.02).

Conclusion

Our data showed that imaging-based PA was associated with malignancy or invasive carcinoma regardless of abrupt change in the caliber of MPD in IPMNs. PA had an acceptable performance in identifying malignant IPMNs.

Usefulness of Imaging and Biological Tools for the Characterization of Portal Vein Thrombosis in Hepatocellular Carcinoma

This study aims to evaluate the performance of contrast-enhanced ultrasound (CEUS) and biological tests to characterize portal vein thrombosis (PVT). We retrospectively analyzed 101 patients with PVT, liver cirrhosis, and hepatocellular carcinoma (HCC). In all patients, demographic, biologic, imaging, and endoscopic data were collected. All patients underwent CEUS and a second line imaging technique (CE-CT/MRI) to characterize PVT. Of the 101 cirrhotic subjects, 77 (76.2%) had HCC. CEUS had 98.6% sensitivity (Se) and 89.3% specificity (Sp) for the characterization of PVT type. A significant correlation was found between alpha-fetoprotein (AFP) levels and the PVT characterization at CEUS (r = 0.28, p = 0.0098) and CT/MRI (r = 0.3, p = 0.0057). Using the AFP rule-out cutoff values for HCC (AFP < 20 ng/dL), 78% of the subjects were correctly classified as having benign PVT, while 100% of the subjects were correctly classified as tumor-in-vein (TIV) when the rule-in cutoff value was used (AFP ≥ 200 ng/dL). Using multiple regression analysis, we obtained a score for classifying PVT. The PVT score performed better than CEUS (AUC—0.99 vs. AUC—0.93, p = 0.025) or AFP serum levels (AUC—0.99 vs. AUC—0.96, p = 0.047) for characterizing PVT. In conclusion, CEUS is a sensitive method for the characterization of PVT. The PVT score had the highest performance for PVT characterization.

Development and Validation of a Preoperative Nomogram for Predicting Benign and Malignant Gallbladder Polypoid Lesions

Purpose

The purpose of this study was to develop and validate a preoperative nomogram of differentiating benign and malignant gallbladder polypoid lesions (GPs) combining clinical and radiomics features.

Methods

The clinical and imaging data of 195 GPs patients which were confirmed by pathology from April 2014 to May 2021 were reviewed. All patients were randomly divided into the training and testing cohorts. Radiomics features based on 3 sequences of contrast-enhanced computed tomography were extracted by the Pyradiomics package in python, and the nomogram further combined with clinical parameters was established by multiple logistic regression. The performance of the nomogram was evaluated by discrimination and calibration.

Results

Among 195 GPs patients, 132 patients were pathologically benign, and 63 patients were malignant. To differentiate benign and malignant GPs, the combined model achieved an area under the curve (AUC) of 0.950 as compared to the radiomics model and clinical model with AUC of 0.929 and 0.925 in the training cohort, respectively. Further validation showed that the combined model contributes to better sensitivity and specificity in the training and testing cohorts by the same cutoff value, although the clinical model had an AUC of 0.943, which was higher than 0.942 of the combined model in the testing cohort.

Conclusion

This study develops a nomogram based on the clinical and radiomics features for the highly effective differentiation and prediction of benign and malignant GPs before surgery.

The Value of Serum Tumor Markers and Blood Inflammation Markers in Differentiating Pancreatic Serous Cystic Neoplasms and Pancreatic Mucinous Cystic Neoplasms

Although many studies have emphasized the prognostic and diagnostic value of tumor markers and various inflammation-related markers, their clinical significance in differentiating benign and malignant pancreatic cystic neoplasms (PCNs) remains to be clarified. The present study explored the value of serum tumor markers and inflammation-related biomarkers in the differentiation of pancreatic serous cystic neoplasms (SCNs) and pancreatic mucinous cystic neoplasms (MCNs). A total of 79 patients with PCNs were included in this study, including 35 patients with SCNs and 44 patients with MCNs. Comparison of baseline data with preoperative results of serum tumor markers and associated inflammatory markers revealed significant differences in carbohydrate antigen 199 (CA199) and "lymphocyte × ALB" (LA) between the two groups (p = 0.0023, p = 0.0149, respectively). Univariate and multivariate regression analyses showed that an increase in CA199 and a decrease in LA were relevant risk factors for MCNs. Finally, the receiver operating characteristic (ROC) curve was generated, and the area under the ROC curve (AUC) was calculated to evaluate the prediction efficiency of each indicator. The results showed that CA199 and LA had good differential diagnostic efficacy for SCNs and MCNs. This is the first to report to demonstrate that LA can be used for the differential diagnosis of SNCs and MCNs.

State-of-the-art surgical treatment of IPMNs

Background

A “pandemic” of incidentally discovered pancreatic cyst neoplasms (PCNs) is ongoing. Among PCNs, intraductal papillary mucinous cystic neoplasms (IPMNs) are the most common and with their complex biology could represent a precursor lesion of pancreatic cancer. Although multiple guidelines exist to guide their treatment, there are still many “gray areas” on indications for surgery for IPMNs.

Methods

The current indications for surgery of IPMNs were reappraised, considering potential discrepancies between available evidence and guidelines policies. The practice at a high-volume center for the diagnosis and treatment of PCN was presented and discussed.

Results

Most IPMNs do not and will never require surgery, as they won’t progress to malignancy. The current literature is solid in identifying high-grade dysplasia (HGD) as the right and timely target for IPMN resection, but how to precisely assess its presence remains controversial and guidelines lack of accuracy in this regard. Multiple tumorigenic pathways of progression of IPMNs exist, and their knowledge will likely lead to more accurate tests for malignancy prediction in the future.

Conclusions

The surgical management of IPMNs still is a matter of debate. Indication for resection should be considered only in highly selected cases with the ideal target of HGD. Clinicians should critically interpret the guidelines’ indications, refer to a multidisciplinary team discussion, and always consider the outcome of an adequate counselling with the patient.