Serous cystic neoplasm of the pancreas: a multinational study of 2622 patients under the auspices of the International Association of Pancreatology and European Pancreatic Club (European Study Group on Cystic Tumors of the Pancreas)

Reassessment of EUS features in preoperative diagnosis of pancreatic serous cystic neoplasm: Lessons to avoid misdiagnosis

OBJECTIVES

Pancreatic serous cystic neoplasm (SCN) is a benign cystic neoplasm that is likely to be surgically resected due to preoperative misdiagnosis or tentative diagnosis even using endoscopic ultrasonography (EUS). We aimed to analyze EUS findings of SCN associated with misdiagnosis.

METHODS

Between January 2012 and September 2023, histologically confirmed pancreatic SCN were included and EUS features were reviewed.

RESULTS

Overall, 294 patients with 300 surgically resected SCNs were included. The median age of the patients was 51 years and 75.9% were females. The lesions were predominantly located in the body/neck/tail of the pancreas (63.0%). The overall preoperative diagnostic rate of SCN was 36.3%, with the most common misdiagnosis being intraductal papillary mucinous neoplasm (IPMN) (31.3%), while 16.3% remained undefined. The preoperative diagnostic rate of SCN varied across different endosonographic morphologies, with oligocystic, macrocystic, microcystic, and solid patterns yielding rates of 12.8%, 37.9%, 76.5%, and 19.2%, respectively. Notably, the presence of central scar and vascularity improved the diagnostic accuracy and correctly identified 41.4% and 52.3% of the lesions. While mucus or pancreatic duct (PD) communication significantly increased the likelihood of misdiagnosis, particularly as IPMN. Multivariate analysis revealed a morphological pattern, mucin-producing signs, wall thickening, vascularity, and PD communication were independent factors related to preoperative misdiagnosis, with an overall accuracy of 82.3%.

CONCLUSIONS

Preoperative diagnosis of SCN remains challenging. The microcystic pattern emerged as a reliable feature, while mucin-producing signs, including mural nodules, mucus, and PD communication, pose diagnostic pitfalls despite the presence of typical central scar or vascularity commonly in SCN.

Rare tumours of the pancreas: monocentric study

PURPOSE

The biology of rare pancreatic tumours, which differs from that of ductal pancreatic cancer, requires increased attention. Although the majority of rare pancreatic tumours are benign, it is difficult to decide whether an invasive component exists without complete removal of the lesion, despite considerable progress in diagnosis. We are investigating a large cohort of patients with histologically confirmed epithelial non-ductal non-neuroendocrine neoplasms of the pancreas.

METHODS

Here we analyze long-term survival from patients, who underwent resection of histologically confirmed epithelial non-ductal non-neuroendocrine neoplasms of the pancreas. At our department between Jan 1st, 1999, and Dec 31st, 2019. The median follow-up was 61 (range 0-168) month. All statistical analyses were performed using SPSS 26.0 (IBM, Chicago, IL, USA) software.

RESULTS

46 patients (48%) were followed up for more than 5 years, 18 patients (19%) for more than 10 years. The 5-year and 10-year survival rates for rare non-invasive pancreatic tumours were 72% and 55% respectively. The proportion of rare tumour entities (non-ductal and non-neuroendocrine) increased continuously and statistically significantly (p = 0.004) from 4.2 to 12.3% in our clinic between 1999 and 2019. If there is no invasive growth yet, there is a varying risk of malignant degeneration in the course of the disease. Therefore, the indication for pancreatic resection is still the subject of discussion.

CONCLUSION

The long-term prognosis of rare epithelial pancreatic tumours after R0 resection-even if they are already malignant-is much better than that of ductal pancreatic cancer.

Imaging of pancreatic serous cystadenoma and common imitators

Pancreatic cystic neoplasms are lesions comprised of cystic components that show different biological behaviors, epidemiology, clinical manifestations, imaging features, and malignant potential and management. Benign cystic neoplasms include serous cystic neoplasms (SCAs). Other pancreatic cystic lesions have malignant potential, such as intraductal papillary mucinous neoplasms and mucinous cystic neoplasms. SCAs can be divided into microcystic (classic appearance), honeycomb, oligocystic/macrocystic, and solid patterns based on imaging appearance. They are usually solitary but may be multiple in von Hippel-Lindau disease, which may depict disseminated involvement. The variable appearances of SCAs can mimic other types of pancreatic cystic lesions, and cross-sectional imaging plays an important role in their differential diagnosis. Endoscopic ultrasonography has helped in improving diagnostic accuracy of pancreatic cystic lesions by guiding tissue sampling (biopsy) or cyst fluid analysis. Immunohistochemistry and newer techniques such as radiomics have shown improved performance for preoperatively discriminating SCAs and their mimickers.

Natural history and growth prediction model of pancreatic serous cystic neoplasms

OBJECTIVE

Serous cystic neoplasms (SCN) are benign pancreatic cystic neoplasms that may require resection based on local complications and rate of growth. We aimed to develop a predictive model for the growth curve of SCNs to aid in the clinical decision making of determining need for surgical resection.

METHODS

Utilizing a prospectively maintained pancreatic cyst database from a single institution, patients with SCNs were identified. Diagnosis confirmation included imaging, cyst aspiration, pathology, or expert opinion. Cyst size diameter was measured by radiology or surgery. Patients with interval imaging ≥3 months from diagnosis were included. Flexible restricted cubic splines were utilized for modeling of non-linearities in time and previous measurements. Model fitting and analysis were performed using R (V3.50, Vienna, Austria) with the rms package.

RESULTS

Among 203 eligible patients from 1998 to 2021, the mean initial cyst size was 31 mm (range 5-160 mm), with a mean follow-up of 72 months (range 3-266 months). The model effectively captured the non-linear relationship between cyst size and time, with both time and previous cyst size (not initial cyst size) significantly predicting current cyst growth (p < 0.01). The root mean square error for overall prediction was 10.74. Validation through bootstrapping demonstrated consistent performance, particularly for shorter follow-up intervals.

CONCLUSION

SCNs typically have a similar growth rate regardless of initial size. An accurate predictive model can be used to identify rapidly growing outliers that may warrant surgical intervention, and this free model (https://riskcalc.org/SerousCystadenomaSize/) can be incorporated in the electronic medical record.

Gradient inflammation in the pancreatic stump after pancreaticoduodenectomy: Two case reports and review of literature

BACKGROUND

Postoperative pancreatic fistula (POPF) contributes significantly to morbidity and mortality after pancreaticoduodenectomy (PD). However, the underlying mechanisms remain unclear. This study explored this pathology in the pancreatic stumps and elucidated the mechanisms of POPF following PD.

CASE SUMMARY

Pathological analysis and 16S rRNA gene sequencing were performed on specimens obtained from two patients who underwent complete pancreatectomy for grade C POPF after PD. Gradient inflammation is present in the pancreatic stump. The apoptosis was lower than that in the normal pancreas. Moreover, neutrophil-dominated inflammatory cells are concentrated in the ductal system. Notably, neutrophils migrated through the ductal wall in acinar duct metaplasia-formed ducts. Additionally, evidence indicates that gut microbes migrate from the digestive tract. Gradient inflammation occurs in pancreatic stumps after PD.

CONCLUSION

The mechanisms underlying POPF include high biochemical activity in the pancreas, mechanical injury, and digestive reflux. To prevent POPF and address pancreatic inflammation and reflux, breaking the link with anastomotic dehiscence is practical.

Diagnosis and Management of Pancreatic Cysts

As pancreatic cyst incidence rises, likely due to the ubiquitous increase in cross-sectional imaging, their management presents multiple challenges for both the practitioner and patient. It is critical that all pancreatic cysts are appropriately characterized, as treatment decisions depend on an accurate diagnosis. Diagnostic modalities such as cytology, biopsy, and cyst fluid biomarkers allow for definitive diagnosis of virtually all lesions. Some cysts, such as intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, and cystic pancreatic endocrine neoplasms, have malignant potential and must be surveyed. Other cysts, such as serous cystadenomas and pancreatic fluid collections, do not have malignant potential. Surveillance strategies vary widely depending on cyst type and size and while multiple medical societies advocate surveillance, their published surveillance guidelines are heterogenous. Cysts with high-risk stigmata or worrisome features are usually resected, depending on the patient's surgical fitness. In patients unfit for resection, newer endoscopic ablative techniques are advocated. Controversial aspects regarding cyst management include whether surveillance can be stopped, how surveillance should be performed, and the extensive financial burden cyst management places on the health care system. Further study into the natural history of cystic lesions, including definitive determination of the rate of malignant transformation for each cyst type, is essential.

Radiomics advances in the evaluation of pancreatic cystic neoplasms

With the development of medical imaging, the detection rate of pancreatic cystic neoplasms (PCNs) has increased greatly. Serous cystic neoplasm, solid pseudopapillary neoplasm, intraductal papillary mucinous neoplasm and mucinous cystic neoplasm are the main subtypes of PCN, and their treatment options vary greatly due to the different biological behaviours of the tumours. Different from conventional qualitative imaging evaluation, radiomics is a promising noninvasive approach for the diagnosis, classification, and risk stratification of diseases involving high-throughput extraction of medical image features. We present a review of radiomics in the diagnosis of serous cystic neoplasm and mucinous cystic neoplasm, risk classification of intraductal papillary mucinous neoplasm and prediction of solid pseudopapillary neoplasm invasiveness compared to conventional imaging diagnosis. Radiomics is a promising tool in the field of medical imaging, providing a noninvasive, high-performance model for preoperative diagnosis and risk stratification of PCNs and improving prospects regarding management of these diseases. Further studies are warranted to investigate MRI image radiomics in connection with PCNs to improve the diagnosis and treatment strategies in the management of PCN patients.

EUS-guided fine needle aspiration-based clues to mistaken or uncertain identity: serous pancreatic cysts

BACKGROUND/OBJECTIVES

Pancreatic serous cystic neoplasms (SCN) present a diagnostic challenge given their increasing frequency of detection and benign nature yet relatively high rate of misdiagnosis. Here, imaging and analyses associated with EUS-guided fine-needle aspiration (EUS-FNA) are evaluated for their ability to provide a correct preoperative diagnosis of SCN.

METHODS

A surgical cohort with confirmed pathological diagnosis of SCN (n = 62) and a surveillance cohort with likely SCN (n = 31) were assessed for imaging (CT/MRI/EUS) and EUS-FNA-based analyses (cytology/DNA analysis for Von Hippel-Lindau [VHL] gene alterations/biomarkers).

RESULTS

In the surgical cohort, CT/MRI and EUS respectively predicted SCN in 4 of 58(7%) and 19 of 62(31%). Cyst fluid cytology and VHL alterations predicted SCN in 1 of 51(2%) and 5 of 21(24%), respectively. High specificity cyst fluid biomarkers (vascular endothelial growth factor [VEGF]/glucose/carcinoembryonic antigen [CEA]/amylase) correctly identified SCN in 25 of 27(93%). In the surveillance cohort, cyst fluid biomarkers predicted SCN in 12 of 12(100%) while VHL alterations identified SCN 3 of 10(30%).

CONCLUSION

High specificity cyst fluid biomarkers provided the most sensitive means of diagnosing SCN preoperatively. To obtain a preoperative diagnosis of SCN at the highest level of certainty, a multidisciplinary approach should be taken to inform appropriate SCN management.

MiR-200b categorizes patients into pancreas cystic lesion subgroups with different malignant potential

Extracellular vesicles (EV) carry their cargo in a membrane protected form, however, their value in early diagnostics is not well known. Although pancreatic cysts are heterogeneous, they can be clustered into the larger groups of pseudocysts (PC), and serous and mucinous pancreatic cystic neoplasms (S-PCN and M-PCN, respectively). In contrast to PCs and S-PCNs, M-PCNs may progress to malignant pancreatic cancers. Since current diagnostic tools do not meet the criteria of high sensitivity and specificity, novel methods are urgently needed to differentiate M-PCNs from other cysts. We show that cyst fluid is a rich source of EVs that are positive and negative for the EV markers CD63 and CD81, respectively. Whereas we found no difference in the EV number when comparing M-PCN with other pancreatic cysts, our EV-based biomarker identification showed that EVs from M-PCNs had a higher level of miR-200b. We also prove that not only EV-derived, but also total cyst fluid miR-200b discriminates patients with M-PCN from other pancreatic cysts with a higher sensitivity and specificity compared to other diagnostic methods, providing the possibility for clinical applications. Our results show that measuring miR-200b in cyst fluid-derived EVs or from cyst fluid may be clinically important in categorizing patients.

Comprehensive characterisation of acinar cystic transformation of the pancreas: a systematic review

AIMS

Acinar cystic transformation (ACT) of the pancreas is a rare pancreatic cystic lesion. Owing to its rarity, comprehensive histomolecular characterisation of this entity is still lacking. We aim to perform a systematic review on this controversial entity.

METHODS

We searched PubMed, SCOPUS and Embase through May 2023 to identify all studies on ACTs. Clinicopathological, immunohistochemical (IHC) and molecular data have been extracted and analysed.

RESULTS

Overall, there were 121 cases of ACTs in the literature. ACT had a female predominance (65.3% of patients), and a mean size of 4.8 cm. ACT was more often unifocal (71.9%) and multiloculate (61.2%). Histologically, the cysts were lined by an acinar epithelium, sometimes harbouring ductal-like areas (18.2%). In five cases (4.1%), an intralesional pancreatic intraepithelial neoplasia (PanIN) was reported. Preoperative diagnosis is challenging. After surgical resection, all patients were alive and disease free during follow-up except one patient who developed a second ACT after resection. By IHC, all lesions were positive for acinar markers; cytokeratin 7 and 8/18/19 were usually positive, and Ki-67 was invariably ≤3%. At the molecular level, three cases demonstrated genetic alterations: one showed multiple chromosomal gains, and other two harboured somatic mutations of KRAS and SMO genes (one mutation per case).

CONCLUSIONS

Globally considered, our findings demonstrated that ACT is a benign entity, without the need of surgical resection with the exception of symptomatic lesions. The rare occurrence of intracystic PanINs and driver mutations suggest considering follow-up if a preoperative diagnosis of ACT can be made.

Clinical characteristics and survival prediction of surgical patients with invasive pancreatic cystic neoplasm: a large retrospective study over two decades

PURPOSES

Invasive pancreatic cystic neoplasms (iPCNs) are an uncommon and biologically heterogeneous group of malignant neoplasms. We aimed to investigate the clinicopathological characteristics of iPCN patients and to develop nomograms for individual survival prediction after radical surgery.

METHODS

Data of patients diagnosed with iPCN and pancreatic ductal adenocarcinoma (PDAC) between 2000 and 2018 from the SEER database were retrieved. The differences in clinical outcomes were evaluated using the Kaplan-Meier analysis. Nomograms were proposed based on the Cox regression model and internally validated by C-index, area under the curve (AUC) value, and calibration plot.

RESULTS

A total of 7777 iPCN patients and 154,336 PDAC patients were enrolled. Most neoplasms were advanced, with 63.1% at stage IV. The 3-year overall survival (OS) and cancer-specific survival (CSS) rates in surgical patients were as follows: 45.7% and 50.1% for invasive intraductal papillary mucinous neoplasm (IPMN), 54.8% and 59.3% for invasive mucinous cystic neoplasm (MCN), 97.8% and 98.2% for invasive solid pseudopapillary neoplasm (SPN), 88.9% and 88.9% for invasive serous cystic neoplasm (SCN), and 27.3% and 30.5% for PDAC. Subgroup analyses showed no clinical benefit from chemotherapy or radiotherapy in lymph node-negative iPCN patients who underwent surgery. The following variables associated with OS and CSS were identified: age, race, chemotherapy, radiotherapy, histologic type, pathological grade, regional nodes examined, and T, N, and M stage. The nomograms had good discrimination and calibration by internal validation, with an AUC value of 0.800 for 3-year OS and 0.814 for 3-year CSS.

CONCLUSION

Our study showed that the prognosis of iPCN patients was significantly better than PDAC patients. The proposed nomograms demonstrated substantially better discrimination and calibration.

Rare Solid Pancreatic Lesions on Cross-Sectional Imaging

Several solid lesions can be found within the pancreas mainly arising from the exocrine and endocrine pancreatic tissue. Among all pancreatic malignancies, the most common subtype is pancreatic ductal adenocarcinoma (PDAC), to a point that pancreatic cancer and PDAC are used interchangeably. But, in addition to PDAC, and to the other most common and well-known solid lesions, either related to benign conditions, such as pancreatitis, or not so benign, such as pancreatic neuroendocrine neoplasms (pNENs), there are solid pancreatic lesions considered rare due to their low incidence. These lesions may originate from a cell line with a differentiation other than exocrine/endocrine, such as from the nerve sheath as for pancreatic schwannoma or from mesenchymal cells as for solitary fibrous tumour. These rare solid pancreatic lesions may show a behaviour that ranges in a benign to highly aggressive malignant spectrum. This review includes cases of an intrapancreatic accessory spleen, pancreatic tuberculosis, solid serous cystadenoma, solid pseudopapillary tumour, pancreatic schwannoma, purely intraductal neuroendocrine tumour, pancreatic fibrous solitary tumour, acinar cell carcinoma, undifferentiated carcinoma with osteoclastic-like giant cells, adenosquamous carcinoma, colloid carcinoma of the pancreas, primary leiomyosarcoma of the pancreas, primary and secondary pancreatic lymphoma and metastases within the pancreas. Therefore, it is important to determine the correct diagnosis to ensure optimal patient management. Because of their rarity, their existence is less well known and, when depicted, in most cases incidentally, the correct diagnosis remains challenging. However, there are some typical imaging features present on cross-sectional imaging modalities that, taken into account with the clinical and biological context, contribute substantially to achieve the correct diagnosis.

A case report: Serous cystadenoma in the pancreas turned malignant

Serous cystadenomas represent 16% of pancreatic serous neoplasms. It can be subdivided into 4 variants: polycystic, oligocystic, honeycomb and solid. Such tumors rarely turn malignant. Most are asymptomatic at the time of diagnosis, but symptomatic patients mainly suffer from abdominal pain and pancreaticobiliary symptoms. Due to the usually benign status, no follow-up or surgery is usually required. This case report concerns a histologically proven serous cystadenoma in an 84-year elderly woman. Due to benign status, no follow-up was required. Thirteen years later she was diagnosed with malignant transformation on computed tomography.

Pancreatic Cystic Lesions: Next Generation of Radiologic Assessment

Pancreatic cystic lesions are frequently identified on cross-sectional imaging. As many of these are presumed branch-duct intraductal papillary mucinous neoplasms, these lesions generate much anxiety for the patients and clinicians, often necessitating long-term follow-up imaging and even unnecessary surgical resections. However, the incidence of pancreatic cancer is overall low for patients with incidental pancreatic cystic lesions. Radiomics and deep learning are advanced tools of imaging analysis that have attracted much attention in addressing this unmet need, however, current publications on this topic show limited success and large-scale research is needed.

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.

Pancreatic Cystic Lesions: Imaging Techniques and Diagnostic Features

The detection of incidental pancreatic cystic lesions has increased over time. It is crucial to separate benign from potentially malignant or malignant lesions to guide management and reduce morbidity and mortality. The key imaging features used to fully characterize cystic lesions are optimally assessed by contrast-enhanced magnetic resonance imaging/magnetic resonance cholangiopancreatography, with pancreas protocol computed tomography offering a complementary role. While some imaging features have high specificity for a particular diagnosis, overlapping imaging features between diagnoses may require further investigation with follow-up diagnostic imaging or tissue sampling.

Cystic pancreatic neoplasms in a tertiary gastroenterologic referral center: Evaluation of the diagnostic accuracy of endoscopic ultrasound, progression rate and malignancy rate in a large unicentric cohort

INTRODUCTION

Cystic pancreatic neoplasms (CPN) are frequently diagnosed due to better diagnostic techniques and patients becoming older. However, diagnostic accuracy of endoscopic ultrasound (EUS) and value of follow-up are still unclear.

MATERIAL AND METHODS

The aim of our retrospective study was to investigate the frequency of different cystic pancreatic neoplasms (intraductal papillary mucinous neoplasm [IPMN], serous and mucinous cystadenoma, solid pseudopapillary neoplasia), diagnostic accuracy, size progression, and rate of malignancy using EUS in a tertiary reference center in Germany. Between January 1, 2012 and December 31, 2018, 455 patients were diagnosed with cystic pancreatic lesions (798 EUS examinations).

RESULTS

Endoscopic ultrasound diagnosed 223 patients with cystic pancreatic neoplasms, including 138 (61.9%) patients with branch duct IPMN, 16 (7.2%) with main duct IPMN, and five (2.2%) with mixed-type IPMN. In the largest subgroup of branch duct IPMN, cysts were size progressive in 20 patients (38.5%). Fine needle aspiration (FNA) was performed in 21 patients, and confirmed the suspected diagnosis in 12/21 patients. 28 surgical resections were performed, in 7/28 patients (25%), high-grade dysplasia or cancer was diagnosed. Endoscopic ultrasound diagnosis of serous and mucinous cystic pancreatic neoplasms was correct in 68.4%.

CONCLUSIONS

Endoscopic ultrasound differential diagnosis of CPNs is challenging. Even in a tertiary expert center, differentiation of serous and mucinous cystic neoplasia is not guaranteed. Relevant size progression of CPN, however, is rare, as is the rate of malignancy. The data of this study suggest that morphologic criteria to assess pancreatic cysts alone are not sufficient to allow a clear diagnosis. Hence, for the improved assessment of pancreatic cysts, EUS should be combined with additional tests and techniques such as MRT/MRCP, contrast-enhanced EUS, and/or FNA/fine needle biopsy including fluid analysis. The combination and correlation of imaging studies with EUS findings is mandatory.

Artificial Intelligence in the Diagnosis and Treatment of Pancreatic Cystic Lesions and Adenocarcinoma

Pancreatic cancer is projected to become the second leading cause of cancer-related mortality in the United States by 2030. This is in part due to the paucity of reliable screening and diagnostic options for early detection. Amongst known pre-malignant pancreatic lesions, pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasms (IPMNs) are the most prevalent. The current standard of care for the diagnosis and classification of pancreatic cystic lesions (PCLs) involves cross-sectional imaging studies and endoscopic ultrasound (EUS) and, when indicated, EUS-guided fine needle aspiration and cyst fluid analysis. However, this is suboptimal for the identification and risk stratification of PCLs, with accuracy of only 65-75% for detecting mucinous PCLs. Artificial intelligence (AI) is a promising tool that has been applied to improve accuracy in screening for solid tumors, including breast, lung, cervical, and colon cancer. More recently, it has shown promise in diagnosing pancreatic cancer by identifying high-risk populations, risk-stratifying premalignant lesions, and predicting the progression of IPMNs to adenocarcinoma. This review summarizes the available literature on artificial intelligence in the screening and prognostication of precancerous lesions in the pancreas, and streamlining the diagnosis of pancreatic cancer.

Rare Non-Neuroendocrine Pancreatic Tumours

The most common tumour of the pancreas is ductal adenocarcinoma (PDAC). It remains one of the most lethal non-neuroendocrine solid tumours despite the use of a multi-approach strategy. Other, less-common neoplasms, which are responsible for 15% of pancreatic lesions, differ in treatment and prognosis. Due to the low incidence rate, there is a lack of information about the rarest pancreatic tumours. In this review, we described six rare pancreatic tumours: intraductal papillary mucinous neoplasm (IPMN), mucinous cystadenoma (MCN), serous cystic neoplasm (SCN), acinar cell carcinoma (ACC), solid pseudopapillary neoplasm (SPN) and pancreatoblastoma (PB). We distinguished their epidemiology, clinical and gross features, covered the newest reports about courses of treatment and systematised differential diagnoses. Although the most common pancreatic tumour, PDAC, has the highest malignant potential, it is still essential to properly classify and differentiate less-common lesions. It is vital to continue the search for new biomarkers, genetic mutations and the development of more specific biochemical tests for determining malignancy in rare pancreatic neoplasms.

Clinical Characteristics of Patients With Surgically Resected Pancreatic Cysts: A Retrospective Analysis of 136 Patients

OBJECTIVES

To retrospectively analyze the characteristics of pancreatic cysts with respect to histopathological diagnosis and various diagnostic imaging tools.

METHODS

The clinical features of 136 patients and characteristics of histopathologically diagnosed cysts were retrospectively assessed. The diagnostic accuracy of endoscopic ultrasound (EUS), computed tomography (CT), and magnetic resonance imaging (MRI) for pancreatic cysts was compared. Risk factors for high-grade dysplasia/invasive cancer in patients with intraductal papillary mucinous neoplasms (IPMNs) were also determined.

RESULTS

The final analysis included 30 serous cystic neoplasms (SCNs) (21.6%), 13 mucinous cystic neoplasms (MCNs) (9.4%), 65 IPMNs (46.8%), and 13 solid pseudopapillary neoplasms (SPNs) (9.4%). The percentage of women with MCNs, SPNs, SCNs, and IPMNs was 100.0, 76.9, 73.3, and 47.7%, respectively (P < .001). The percentages of patients over 60 years of age with IPMNs, SCNs, MCNs, and SPNs were 73.9, 23.3, 0, and 0%, respectively (P < .001). The percentage of cysts located in the body and tail of the pancreas in MCNs, SCNs, SPNs, and IPMNs was 100, 70, 53.9, and 46.2%, respectively (P < .001). A unique honeycomb appearance was observed in 26.7% of SCNs. The overall diagnostic accuracy of EUS, CT, and MRI for pancreatic cysts was 82.6, 72.5, and 73.9%, respectively. Lesion size and presence of solid components were independent predictors of high-risk IPMNs.

CONCLUSIONS

Patient characteristics and cyst features can help to differentiate pancreatic cyst types and identify high-risk IPMNs. The diagnostic accuracy of EUS for pancreatic cysts is superior to that of CT and MRI.

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.

Pancreatic Cystic Tumors: A Single-Center Observational Study

Background and Objectives: The aim of the study was to analyze the prevalence and characteristics of pancreatic cystic tumors (PCTs). Material and Methods: A retrospective analysis of the medical records of 124 patients, 102 (69%) women and 46 (31%) men, who had undergone surgery for pancreatic cystic tumors in 2014-2018. Among 148 pancreatic cysts, 24 (16%) were non-neoplasmatic and 124 (84%) were neoplasmatic. The neoplasmatic cysts (n = 124) were included in our analysis. There were five main types of PCTs: IPMN (intraductal papillary mucinous neoplasm) (n = 45), MCN (mucinous cystic neoplasm) (n = 30), SCN (serous cystic neoplasm) (n = 28), SPN (solid pseudopapillary neoplasm) (n = 8), and CPEN (cystic pancreatic endocrine neoplasm) (n = 8), as well as mixed-type tumors (n = 5). Results: A statistically significant dependency between PCT type and age was proven (p= 0.0001): IPMNs were observed in the older group of patients with an average age of 66.12 (40-79) years while SPNs were noted in the youngest group of patients with an average age of 36.22 (22-55) years. A statistically significant association between PCT type and gender (p = 0.0001) was found: IPMNs occurred among 24 (53.33%) men and 21 (46.6%) women. In the MCN and SPN groups, all patients were female (100%). Among the SCN group, the majority were women (27 (96.43%)), and there was only 1 (3.57%) man. A statistically significant dependency between PCT type and size was proven (p = 0.0007). The mean size of IPMNs was the smallest 2.95 (0.6-10 cm) and the mean size of MCNs was the largest 6.78 (1.5-19 cm). A statistically significant dependency between PCT type and tumor location was proven (p = 0.000238). The most frequent location of IPMN was the pancreatic head: 27 (60%). MCN was most frequently located in the pancreatic tail (18 (60%)). Most (10/28) SCNs were found in the pancreatic tail (10 (35.71%)). CPENs were most frequently located in the pancreatic tail (three (37.5%)) and pancreatic body and tail (three (37.5%)). SPNs were located commonly in the pancreatic head (five (62.5%)). The type of surgery depended on the tumor location. The most frequent surgery for IPMNs was pancreatoduodenectomy (44.4%), while for MCNs and SCNs, it was distal pancreatectomy (81%). The postoperative morbidity and mortality were 34.68% and 1.61%, respectively. Postoperative pancreatic fistula (POPF) was the most frequent (29%) complication. Conclusions: IPMN was the most frequent resected PCT in our material. A statistically significant association between the type of cyst and location within the pancreas, size, local lymph node involvement, and patient's age and sex was proved. POPF was the most frequent postoperative complication. In patients with PCTs, due to substantial postoperative morbidity, adequate patient selection, considering both the surgical risk as well as the long-term risk of malignant transformation, is very important during qualification for surgery.

Surgical treatment for pancreatic cystic lesions-implications from the multi-center and prospective German StuDoQ|Pancreas registry

PURPOSE

The detection of pancreatic cystic lesions (PCL) causes uncertainty for physicians and patients, and international guidelines are based on low evidence. The extent and perioperative risk of resections of PCL in Germany needs comparison with these guidelines to highlight controversies and derive recommendations.

METHODS

Clinical data of 1137 patients who underwent surgery for PCL between 2014 and 2019 were retrieved from the German StuDoQ|Pancreas registry. Relevant features for preoperative evaluation and predictive factors for adverse outcomes were statistically identified.

RESULTS

Patients with intraductal papillary mucinous neoplasms (IPMN) represented the largest PCL subgroup (N = 689; 60.6%) while other entities (mucinous cystic neoplasms (MCN), serous cystic neoplasms (SCN), neuroendocrine tumors, pseudocysts) were less frequently resected. Symptoms of pancreatitis were associated with IPMN (OR, 1.8; P = 0.012) and pseudocysts (OR, 4.78; P < 0.001), but likewise lowered the likelihood of MCN (OR, 0.49; P = 0.046) and SCN (OR, 0.15, P = 0.002). A total of 639 (57.2%) patients received endoscopic ultrasound before resection, as recommended by guidelines. Malignancy was histologically confirmed in 137 patients (12.0%), while jaundice (OR, 5.1; P < 0.001) and weight loss (OR, 2.0; P = 0.002) were independent predictors. Most resections were performed by open surgery (N = 847, 74.5%), while distal lesions were in majority treated using minimally invasive approaches (P < 0.001). Severe morbidity was 28.4% (N = 323) and 30d mortality was 2.6% (N = 29). Increased age (P = 0.004), higher BMI (P = 0.002), liver cirrhosis (P < 0.001), and esophageal varices (P = 0.002) were independent risk factors for 30d mortality.

CONCLUSION

With respect to unclear findings frequently present in PCL, diagnostic means recommended in guidelines should always be considered in the preoperative phase. The therapy of PCL should be decided upon in the light of patient-specific factors, and the surgical strategy needs to be adapted accordingly.

Pancreatic Cystic Neoplasms: Diagnosis and Management

Pancreatic cancer is one of the most lethal cancers, largely related to the difficulties with early detection, as it typically presents in later stages. Pancreatic cystic neoplasms (PCN) are commonly diagnosed as incidental findings on routine imaging. PCN is becoming more frequently detected with the increasing ease and frequency of obtaining cross-sectional images. Certain subtypes of pancreatic cysts have the potential to progress to malignancy, and therefore, clinicians are tasked with creating a patient-centered management plan. The decision of whether to undergo surgical resection or interval surveillance can be challenging given the criteria, including PCN size, pancreatic duct dilation, presence of a mural nodule, and clinical symptoms that play a potential role in risk stratification. Furthermore, the guidelines available from the major gastrointestinal societies all differ in their management recommendations. In this review, we detail an overview of the different types of PCNs and compare major guidelines for both diagnosis and management. We include emerging evidence for next-generation sequencing as well as confocal needle endomicroscopy to aid in the diagnosis and determination of malignancy potential and diagnosis.

Differential diagnosis of pancreatic cystic neoplasms through a radiomics-assisted system

Pancreatic cystic neoplasms (PCNs) are a group of heterogeneous diseases with distinct prognosis. Existing differential diagnosis methods require invasive biopsy or prolonged monitoring. We sought to develop an inexpensive, non-invasive differential diagnosis system for PCNs based on radiomics features and clinical characteristics for a higher total PCN screening rate. We retrospectively analyzed computed tomography images and clinical data from 129 patients with PCN, including 47 patients with intraductal papillary mucinous neoplasms (IPMNs), 49 patients with serous cystadenomas (SCNs), and 33 patients with mucinous cystic neoplasms (MCNs). Six clinical characteristics and 944 radiomics features were tested, and nine features were finally selected for model construction using DXScore algorithm. A five-fold cross-validation algorithm and a test group were applied to verify the results. In the five-fold cross-validation section, the AUC value of our model was 0.8687, and the total accuracy rate was 74.23%, wherein the accuracy rates of IPMNs, SCNs, and MCNs were 74.26%, 78.37%, and 68.00%, respectively. In the test group, the AUC value was 0.8462 and the total accuracy rate was 73.61%. In conclusion, our research constructed an end-to-end powerful PCN differential diagnosis system based on radiomics method, which could assist decision-making in clinical practice.

Endovascular treatment of haemorrhagic pancreatic serous cystadenoma

BACKGROUND

Pancreatic microcystic serous cystadenoma are rare benign pancreatic tumors. No treatment is needed in most cases as this lesion is often discovered incidentally. Surgery is not required except in symptomatic cases.

CASE PRESENTATION

We report herein a rare case of pancreatic serous cystadenoma complicated with a hemorrhage in a 95 years old patient treated with arterial embolization since surgery was not possible. The patient recovered without any adverse events or bleed recurrence in the 6 months following the procedure.

CONCLUSION

Hemorrhage secondary to a pancreatic serous cystadenoma was successfully treated with arterial embolization, which may represent an alternative therapeutic option to surgery.

A case of serous cystic neoplasm with tumor growth acceleration leading to extrapancreatic invasion

Serous cystic neoplasm (SCN) is a potentially malignant and invasive disease. However, there are no established guidelines regarding the surgical management of SCN. Here, we report a case of SCN with jejunal invasion that ultimately required a distal pancreatectomy with partial resection of the jejunum. The patient was a 65-year-old female who was referred to our department after a diagnosis of SCN in the pancreatic tail. CT and MRI showed a 75-mm multifocal cystic mass with calcifications; the splenic vein and left adrenal vein were entrapped within the tumor. Furthermore, the tumor was in contact with the beginning of the jejunum. Finally, she underwent a posterior radical antegrade modular pancreatosplenectomy with a partial wedge-shaped resection of the jejunum. Histological findings indicated serous cystadenoma. In addition, the tumor cells were found to have infiltrated the jejunal muscularis propria in some areas, suggesting that the tumor had malignant potential. Currently, 14 months have passed since surgery and there is no evidence of metastasis or recurrence. Surveillance and the decision to perform surgical resection should be made based on tumor size and growth rate to avoid malignant transformation as well as to provide SCN patients with organ-sparing, less invasive surgery.

Central pancreatectomy prevents postoperative diabetes

BACKGROUND

Central pancreatectomy (CP) can be performed as an alternative surgical approach to distal pancreatectomy (DP) in the treatment of benign or low-grade malignant lesions located in the neck and body of the pancreas, aiming to reduce loss of parenchyma and therefore organ failure. The objective of this study was to evaluate the short- and long-term outcome of CP in comparison to DP.

METHODS

Patients who received CP in a large tertiary care pancreatic surgery center between 2001 and 2020 were identified from a prospectively maintained database and compared via propensity score matching with patients receiving DP during the same time period. Perioperative rate of complications and long-term outcome of pancreatic endocrine and exocrine function were evaluated.

RESULTS

One hundred and seven patients undergoing open CP were compared to 107 patients with open DP. No significant difference in rates or severity of most surgical complications could be found including postoperative pancreatic fistula, intraabdominal fluid collection, delayed gastric emptying and wound infection. However, patients receiving CP had a significantly higher risk of grade C postpancreatectomy hemorrhage (PPH) (CP: 10 patients, 9.3% versus DP: 1 patient, 0.9%; p = .0019). Perioperative mortality was comparable. Long-term follow-up of 60 matched pairs revealed significantly less patients with new-onset diabetes after CP (eight patients, 13.3%) compared to DP (22 patients, 36.7%, p = .0056).

CONCLUSION

CP offers an improved endocrine long-term outcome at the expense of a higher risk of PPH without increased perioperative mortality. As evidence on this parenchyma sparing surgical technique is sparse, more prospective data are needed.

Accuracy and agreement of a large panel of endosonographers for endomicroscopy-guided virtual biopsy of pancreatic cystic lesions

BACKGROUND

Although emerging data evidences that EUS-guided needle-based confocal laser endomicroscopy (nCLE) accurately diagnoses pancreatic cystic lesions (PCLs), there are a lack of interobserver agreement (IOA) studies utilizing reference histopathological diagnosis and for specific PCL subtypes. Hence, we sought to assess the IOA, intra-observer reliability (IOR), and diagnostic performance of EUS-nCLE using a large cohort of patients with histopathological diagnosis amongst a broad panel of international observers.

METHODS

EUS-nCLE videos (n = 76) of subjects with PCLs [intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), serous cystadenoma (SCA), pseudocyst, and cystic-neuroendocrine tumors/solid pseudopapillary neoplasm (cystic-NET/SPN)], simulating clinical prevalence rates were obtained from 3 prospective studies. An international panel of 13 endosonographers with nCLE experience, blinded to all PCL data, evaluated the video library twice with a two-week washout for PCL differentiation (mucinous vs. non-mucinous) and subtype diagnosis.

RESULTS

The IOA (κ = 0.82, 95% CI 0.77-0.87) and IOR (κ = 0.82, 95% CI 0.78-0.85) were "almost perfect" to differentiate mucinous vs. non-mucinous PCLs. For PCL subtype, IOA was highest for SCA (almost perfect; κ = 0.85), followed by IPMN (substantial, κ = 0.72), and cystic-NET/SPN (substantial, κ = 0.73). The IOA was moderate for MCN (κ = 0.47), and pseudocyst (κ = 0.57). Compared to histopathology, observers differentiated mucinous vs. non-mucinous PCLs with high accuracy (94.8%, 95% CI 93.3-96.1). For detecting specific PCLs subtypes, EUS-nCLE was highly accurate in diagnosing non-mucinous cysts (SCA: 98%; cystic-NET/SPN: 96%; pseudocyst: 96%) and slightly less accurate for mucinous lesions (IPMN: 86%; MCN: 84%).

CONCLUSION

Diagnosis of PCLs by EUS-nCLE guided virtual biopsy is very accurate and reliable for the most prevalent pancreatic cysts in clinical practice.

Improving diagnostic accuracy and appropriate indications for surgery in pancreatic cystic neoplasms: the role of EUS

BACKGROUND AND AIMS

Pancreatic cystic neoplasms (PCNs) represent a difficult preoperative diagnosis despite improvements in imaging. In this study, we compared preoperative and final pathologic diagnosis in a large cohort of resected PCNs, evaluating diagnostic accuracy with a specific focus on the value of EUS.

METHODS

A retrospective analysis of patients undergoing resection between 2009 and 2019 for presumed PCNs was performed. Preoperative workup was reviewed by analyzing the role of imaging and EUS. Patients with a benign histology who did not show absolute indication were categorized as "delayable surgery."

RESULTS

Of 585 patients who were retrospectively analyzed, in 108 (18.5%) final histology did not confirm preoperative diagnosis. EUS was associated with a lower rate of incorrect diagnosis (16%; P = .03), but the risk of overtreatment was similar regardless of instrumental diagnostic path (33/131 vs 68/328, P = .298). Dilatation of the main pancreatic duct and cytologic sampling were the only variables independently associated with a correct diagnosis (P < .001 and P = .041, respectively). Based on clinical presentation and final histology, pancreatic resection could have been spared or delayed in 101 of 459 patients (22%), and this was influenced by age (odds ratio [OR], .97; P = .002), cyst larger than 30 mm (OR, 1.89; P = .005), and type of operation (OR, 3.46 [P < .001] and 3.18 [P = .023] for distal pancreatectomies and other resections, respectively).

CONCLUSIONS

The overall risk of unnecessary immediate surgery for PCNs is about 22% in a high-volume referral center. EUS with cytologic sampling is a useful procedure in the diagnostic management of PCNs, improving their diagnostic accuracy.

Integrating Molecular Analysis into the Pathologic Evaluation of Pancreatic Cysts

The development of cross-sectional imaging techniques has enhanced the detection of pancreatic cystic lesions (PCLs). PCLs are found in approximately 2% of the general population, often as incidentally detected lesions on computed tomography or MRI during the evaluation of other medical conditions. Broadly, PCLs are classified as mucinous or nonmucinous. Mucinous PCLs include mucinous cystic neoplasms and intraductal papillary mucinous neoplasms. Nonmucinous PCLs include pseudocysts, serous cystadenomas, solid pseudopapillary neoplasms, and cystic pancreatic neuroendocrine tumors, as well as cystic acinar cell carcinoma, cystic degeneration of pancreatic ductal adenocarcinoma, lymphoepithelial cyst, and others.

Pancreatic Cystic Neoplasms

Early detection of high-risk pancreatic cystic lesions enables potentially curative surgical resection, and early detection of lesions without worrisome features may lead to appropriate surveillance. Regrettably, differentiating premalignant and malignant cysts from nonmalignant ones remains challenging. However, emerging additional diagnostic tools, including the needle biopsy with microforceps and needle-based confocal laser endomicroscopy, are of exciting potential along with cyst fluid analysis".

Artificial intelligence for the detection of pancreatic lesions

PURPOSE

Pancreatic cancer is one of the most lethal neoplasms among common cancers worldwide, and PCLs are well-known precursors of this type of cancer. Artificial intelligence (AI) could help to improve and speed up the detection and classification of pancreatic lesions. The aim of this review is to summarize the articles addressing the diagnostic yield of artificial intelligence applied to medical imaging (computed tomography [CT] and/or magnetic resonance [MR]) for the detection of pancreatic cancer and pancreatic cystic lesions.

METHODS

We performed a comprehensive literature search using PubMed, EMBASE, and Scopus (from January 2010 to April 2021) to identify full articles evaluating the diagnostic accuracy of AI-based methods processing CT or MR images to detect pancreatic ductal adenocarcinoma (PDAC) or pancreatic cystic lesions (PCLs).

RESULTS

We found 20 studies meeting our inclusion criteria. Most of the AI-based systems used were convolutional neural networks. Ten studies addressed the use of AI to detect PDAC, eight studies aimed to detect and classify PCLs, and 4 aimed to predict the presence of high-grade dysplasia or cancer.

CONCLUSION

AI techniques have shown to be a promising tool which is expected to be helpful for most radiologists' tasks. However, methodologic concerns must be addressed, and prospective clinical studies should be carried out before implementation in clinical practice.

Comparison of Society Guidelines for the Management and Surveillance of Pancreatic Cysts: A Review

Importance

The identification of incidental pancreas cystic lesions (PCLs) has increased in recent decades with the expanded use and improved sensitivity of cross-sectional imaging. Because the overall risk of malignancy associated with PCLs is low, yet the relative morbidity of pancreatic surgery is high, evidence-based guidelines are necessary for appropriate surveillance and management. Therefore, this article provides a review of existing guidelines regarding surveillance and management of PCLs and highlights recent advances in the diagnostic evaluation of cysts and the postresection management of mucinous lesions.

Observations

There are 5 main guidelines related to the management of PCLs: the American Gastrointestinal Association (AGA) guidelines, the American College of Gastroenterology (ACG) guidelines, the American College of Radiology (ACR) recommendations, the European evidence-based guidelines, and the International Association of Pancreatology (IAP)/Fukuoka guidelines. These guidelines are based on retrospective studies that do not account or control for most tumor- and patient-specific factors. These guidelines also vary in scope, recommendations for surgical resection vs surveillance, as well as duration and type of follow-up.

Conclusions and Relevance

PCL guidelines should be viewed within the context of the data limitations on which they are based. PCL subtype-specific guidelines on surveillance and treatment are needed. In the future, the integration of cyst-specific genomic analysis, as well as evolutions in advanced diagnostic tools, such as cyst fluid next-generation sequencing and EUS-guided confocal laser endomicroscopy, may also better inform treatment guidelines. Owing to the current low-quality evidence on which many guidelines are based and the inherent morbidity of pancreas surgery, it is imperative that patients with PCLs are referred to institutions with advanced diagnostics and a multidisciplinary approach to patient surveillance and management.

Application of Artificial Intelligence in the Management of Pancreatic Cystic Lesions

The rate of incidentally detected pancreatic cystic lesions (PCLs) has increased over the past decade and was recently reported at 8%. These lesions pose a unique challenge, as each subtype of PCL carries a different risk of malignant transformation, ranging from 0% (pancreatic pseudocyst) to 34–68% (main duct intraductal papillary mucinous neoplasm). It is imperative to correctly risk-stratify the malignant potential of these lesions in order to provide the correct care course for the patient, ranging from monitoring to surgical intervention. Even with the multiplicity of guidelines (i.e., the American Gastroenterology Association guidelines and Fukuoka/International Consensus guidelines) and multitude of diagnostic information, risk stratification of PCLs falls short. Studies have reported that 25–64% of patients undergoing PCL resection have pancreatic cysts with no malignant potential, and up to 78% of mucin-producing cysts resected harbor no malignant potential on pathological evaluation. Clinicians are now incorporating artificial intelligence technology to aid in the management of these difficult lesions. This review article focuses on advancements in artificial intelligence within digital pathomics, radiomics, and genomics as they apply to the diagnosis and risk stratification of PCLs.

[Pancreatic cystic space-occupying lesions-Diagnostics, treatment and follow-up care : Current recommendations taking the current German S3 guidelines on pancreatic cancer into account]

Due to their increased detection pancreatic cystic space-occupying lesions are becoming increasingly relevant in the clinical routine and represent a morphologically and biologically heterogeneous and thus clinically demanding as well as potentially (pre)malignant entity. As a result, recommendations for the diagnostics and treatment of pancreatic cystic tumors have now been incorporated into the current German S3 guidelines on pancreatic cancer. The diagnostics of pancreatic cystic space-occupying lesions are based on the following three elements: collection of relevant clinical information, performance of high-resolution imaging procedures and if diagnostic uncertainty persists, puncture diagnostics. Differentiated diagnostics are of essential importance as these represent the basis for an adequate treatment decision. Pancreatic cystic lesions with a relevant risk of malignant transformation, e.g., main duct intraductal papillary mucinous neoplasms (IPMN), followed by mucinous cystic neoplasms (MCN), solid pseudopapillary neoplasms (SPN) and generally pancreatic cystic lesions with risk factors independent of the entity, should be resected, whereas a differentiated and individualized approach is necessary, especially for branch-duct IPMNs. The serous cystic neoplasms (SCN) have no malignant potential and do not require any treatment if they are asymptomatic. Important principles in surgery of pancreatic cancer, such as adequate surgical resection taking oncological standards into account and standardized appropriate histopathological processing of the specimens as well as intraoperative frozen section analysis also play an important role in pancreatic cystic space-occupying lesions. An annual follow-up seems to be meaningful, especially for IPMNs.

State-of-the-Art Update of Pancreatic Cysts

Andrew Canakis.

An update on EUS-guided ablative techniques for pancreatic cystic lesions

Pancreatic cystic lesions (PCLs) are increasingly being recognized due to improvements and widespread use of cross-sectional imaging. With an estimated prevalence of 15% in general population, incidentally discovered PCLs represent a dilemma in management. While pancreatectomies offer a chance of cure, the morbidity is considerable in patients with high surgical risks. More recently, EUS-guided approaches for cyst ablation are being offered in clinical trials for the management of PCLs. EUS-chemoablation studies have progressed from first investigating safety and efficacy of EUS-guided alcohol lavage to single-agent paclitaxel ablation. Recent studies have shown that alcohol lavage may not be required, and long-term resolution can be achieved by chemoablation alone. EUS-guided lauromacrogol ablation and EUS-guided radiofrequency ablation (RFA) are new techniques that have shown promising results in a few small studies. Overall, the current literature suggests that EUS-guided paclitaxel ablation has better cyst resolution rates compared to other existing minimally invasive techniques including ethanol injection, lauromacrogol ablation, or RFA. This article will review EUS-guided PCL ablation approaches and future directions the field is headed into.

Cystic Neoplasms of the Pancreas: Differential Diagnosis and Radiology Correlation

Although the probability of pancreatic cystic neoplasms (PCNs) being detected is raising year by year, their differential diagnosis and individualized treatment are still a challenge in clinical work. PCNs are tumors containing cystic components with different biological behaviors, and their clinical manifestations, epidemiology, imaging features, and malignant risks are different. Some are benign [e.g., serous cystic neoplasms (SCNs)], with a barely possible that turning into malignant, while others display a low or higher malignant risk [e.g., solid pseudopapillary neoplasms (SPNs), intraductal papillary mucinous neoplasms (IPMNs), and mucinous cystic neoplasms (MCNs)]. PCN management should concentrate on preventing the progression of malignant tumors while preventing complications caused by unnecessary surgical intervention. Clinically, various advanced imaging equipment are usually combined to obtain a more reliable preoperative diagnosis. The challenge for clinicians and radiologists is how to accurately diagnose PCNs before surgery so that corresponding surgical methods and follow-up strategies can be developed or not, as appropriate. The objective of this review is to sum up the clinical features, imaging findings and management of the most common PCNs according to the classic literature and latest guidelines.

[Diagnostics and clinical management of premalignant diseases of the pancreas]

Pancreatic cancer is one of the most aggressive solid tumors and still has a poor prognosis. A delayed diagnosis at advanced stages and a poor response to systemic treatment frequently make a curative treatment impossible. Therefore, the identification of high-risk patients and screening them regularly is the most promising approach to improve the prognosis. Chronic pancreatitis as well as neoplastic pancreatic cysts can greatly increase the risk of developing pancreatic cancer. Furthermore, familial syndromes and germline mutations also confer an increased risk for development of pancreatic cancer. This article provides an overview of the various premalignant diseases of the pancreas. The value of the various imaging modalities, such as magnetic resonance imaging and endosonography are particularly discussed as well as the screening interval and the indications for surgical treatment are explained.

Epidemiological Factors Associated With Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Dual Center Case-Control Study

OBJECTIVE

The present study aimed to identify epidemiological factors associated with the development of intraductal papillary mucinous neoplasms (IPMN) of the pancreas comparing patients after IPMN resection with population-based controls.

METHODS

Preoperative data of 811 patients undergoing pancreatic resection for IPMN were matched in a 1:1 ratio with a random sample of volunteers from the Study of Health in Pomerania, which showed no pancreatic cyst greater than 2 mm in magnetic resonance cholangiopancreaticography.

RESULTS

A total of 811 controls with a mean age of 61.9 years (standard deviation, 8.4 years) were matched to cases with a mean age of 66.1 years (standard deviation, 9.3 years). A previous history of pancreatitis, endocrine pancreatic insufficiency was significantly more frequent in IPMN patients compared with controls (P = 0.001). Moreover, adjusted data revealed that urogenital cancer (P = 0.034), colorectal cancer (P = 0.021), as well as first-degree family history of colorectal cancer (P = 0.001) were significantly more frequent in IPMN patients.

CONCLUSIONS

A history of urogenital and colorectal cancer often coincides with IPMN, which have an indication for surgery and are associated with preoperative episodes of pancreatitis and with endocrine insufficiency. Prospective studies are needed to investigate the role of these factors in IPMN development.

Transabdominal ultrasonographic diagnosis of relatively rare pancreatic neoplasms

There are various types of pancreatic neoplasms, and their prognosis and treatment methods are different. Therefore, accurate diagnosis is important to determine the best treatment strategy. Transabdominal ultrasonography is frequently used as a screening examination for diagnostic imaging of pancreatic neoplasms. In this review, we have focused on the characteristics of ultrasonic findings for relatively rare pancreatic neoplasms.

Pancreatic Serous Cystic Neoplasms and Mucinous Cystic Neoplasms: Differential Diagnosis by Combining Imaging Features and Enhanced CT Texture Analysis

Objective

To establish a diagnostic model by combining imaging features with enhanced CT texture analysis to differentiate pancreatic serous cystadenomas (SCNs) from pancreatic mucinous cystadenomas (MCNs).

Materials and Methods

Fifty-seven and 43 patients with pathology-confirmed SCNs and MCNs, respectively, from one center were analyzed and divided into a training cohort (n = 72) and an internal validation cohort (n = 28). An external validation cohort (n = 28) from another center was allocated. Demographic and radiological information were collected. The least absolute shrinkage and selection operator (LASSO) and recursive feature elimination linear support vector machine (RFE_LinearSVC) were implemented to select significant features. Multivariable logistic regression algorithms were conducted for model construction. Receiver operating characteristic (ROC) curves for the models were evaluated, and their prediction efficiency was quantified by the area under the curve (AUC), 95% confidence interval (95% CI), sensitivity and specificity.

Results

Following multivariable logistic regression analysis, the AUC was 0.932 and 0.887, the sensitivity was 87.5% and 90%, and the specificity was 82.4% and 84.6% with the training and validation cohorts, respectively, for the model combining radiological features and CT texture features. For the model based on radiological features alone, the AUC was 0.84 and 0.91, the sensitivity was 75% and 66.7%, and the specificity was 82.4% and 77% with the training and validation cohorts, respectively.

Conclusion

This study showed that a logistic model combining radiological features and CT texture features is more effective in distinguishing SCNs from MCNs of the pancreas than a model based on radiological features alone.