Diagnosis and Management of Pancreatic Cysts

Mucinous cystic neoplasms and simple mucinous cysts are two distinct precursors of pancreatic cancer: clinicopathological, genomic, and transcriptomic characterization

Mucinous cystic neoplasms (MCNs) of the pancreas are macroscopic precursors of pancreatic cancer. A similar cystic lesion but lacking the ovarian-type subepithelial stroma has been recently defined as a simple mucinous cyst (SMC); however, its nature remains unclear. This study aims to define the clinicopathological and molecular profiles of a cohort of MCNs and SMCs of the pancreas and their associated invasive carcinoma. Overall, 23 cases were identified, comprising 19 MCNs and 4 SMCs with co-occurring invasive carcinoma. A multiregional (two samples from each cystic lesion and one from the adenocarcinoma) DNA and RNA sequencing approach was used. The key findings can be summarized as follows: (1) Molecular association: In 22/23 cases (95.7%), the concomitant mucinous cyst and invasive carcinoma shared specific genomic alterations, establishing for the first time that SMC is a true precursor of pancreatic cancer. (2) Clinical behavior: carcinomas arising from SMC appeared to be more aggressive than those arising from MCN. (3) Mutational profile: both cyst types showed significant similarities to conventional pancreatic ductal adenocarcinoma (PDAC), with KRAS and TP53 the most commonly altered genes. (4) Intracystic heterogeneity: while most molecular alterations were present in both analyzed cystic areas, RNF43 showed the highest heterogeneity. (5) CDKN2A: its alterations were predominantly restricted to the invasive component, suggesting a role in driving the invasion in a subset of cases. CNKN2A may also serve as a potential biomarker for identifying high-risk cysts. (6) RNAseq: most cases showed a switch from the classical to the basal transcriptome subtype during the progression from cystic neoplasms to invasive cancers. These findings establish SMCs as new precursors of pancreatic cancer and provide critical insights into the tumorigenesis of MCNs, with potential immediate implications for tumor taxonomy and clinical management. © 2025 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Role of Endoscopy in Clinical Management of Intraductal Papillary Mucinous Neoplasms

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a well-recognized precursor of pancreatic carcinoma. Along with cross-sectional abdominal imaging tests, endoscopic examinations remain the cornerstone in the diagnosis of pancreatic cysts, early detection of IPMN-derived carcinomas, and risk stratification of patients with IPMNs for subsequent surveillance strategies. In particular, endoscopic ultrasound (EUS) facilitates the optimal patient management by providing high-resolution morphological information, and the contrast-enhanced harmonic mode may further enhance diagnostic accuracy. EUS-guided fine-needle aspiration for solid mass and/or cyst fluid is considered for pathological and molecular examinations for the diagnosis of pancreatic cysts and malignancy. Emerging evidence suggests the usefulness of through-the-needle biopsy and confocal laser microendoscopy in this setting. In addition to the undoubtful diagnostic utility, recent studies have demonstrated the potential effect of endoscopic interventions (i.e., ablation) on the control of IPMNs. Despite the increasing role of endoscopy in the clinical management of IPMNs, there remains a gap in our understanding of how to utilize endoscopy in the personalized care for patients with IPMNs (e.g., the optimal interval of EUS) and the prevention of deaths due to pancreatic carcinomas developing concomitantly with IPMNs. This review summarizes the current evidence on the role of endoscopy in both the diagnostic and therapeutic landscapes of clinical management of IPMNs and identifies key clinical unmet needs that should be addressed in future research. Combined with emerging technologies (e.g., artificial intelligence and high-throughput molecular profiling), endoscopy would offer more effective and tailored management strategies for patients with IPMNs.

Research progress of nano drug delivery systems in the anti-tumor treatment of traditional Chinese medicine monomers

Tumors pose a serious threat to global public health and are usually treated from two aspects: tumor cells and tumor microenvironment. Compared with traditional chemotherapy drugs, traditional Chinese medicine (TCM) monomers have advantages in tumor treatment, such as multiple targets, multiple levels and synergistic intervention. However, most TCM active ingredients have disadvantages such as poor water solubility and stability, which restrict their clinical application. Nano drug delivery systems have the functions of improving the bioavailability of TCM anti-tumor active ingredients, enhancing tissue targeting, achieving controlled drug release, and inhibiting tumor multidrug resistance. Compared with free monomers, they have higher therapeutic effects and fewer side effects. This article summarizes five commonly used anti-tumor TCM monomer nanocarriers, including lipid nanomaterials, exosomes, polymer micelles, carbon nanotubes, and dendrimers, and explains their anti-tumor mechanisms after combining with TCM, such as inhibiting tumor cell proliferation and metastasis, regulating tumor microenvironment, etc. At the same time, the potential of nano drug delivery systems combined with radiotherapy and immunotherapy is discussed, as well as the current problems of potential toxicity, long-term stability, and complex amplification process, as well as future development directions, aiming to provide a reference for promoting the clinical application of nano drug delivery systems for TCM anti-tumor active ingredients.

Deep learning-based MVIT-MLKA model for accurate classification of pancreatic lesions: a multicenter retrospective cohort study

BACKGROUND

Accurate differentiation between benign and malignant pancreatic lesions is critical for effective patient management. This study aimed to develop and validate a novel deep learning network using baseline computed tomography (CT) images to predict the classification of pancreatic lesions.

METHODS

This retrospective study included 864 patients (422 men, 442 women) with confirmed histopathological results across three medical centers, forming a training cohort, internal testing cohort, and external validation cohort. A novel hybrid model, Multi-Scale Large Kernel Attention with Mobile Vision Transformer (MVIT-MLKA), was developed, integrating CNN and Transformer architectures to classify pancreatic lesions. The model's performance was compared with traditional machine learning methods and advanced deep learning models. We also evaluated the diagnostic accuracy of radiologists with and without the assistance of the optimal model. Model performance was assessed through discrimination, calibration, and clinical applicability.

RESULTS

The MVIT-MLKA model demonstrated superior performance in classifying pancreatic lesions, achieving an AUC of 0.974 (95% CI 0.967-0.980) in the training set, 0.935 (95% CI 0.915-0.954) in the internal testing set, and 0.924 (95% CI 0.902-0.945) in the external validation set, outperforming traditional models and other deep learning models (P < 0.05). Radiologists aided by the MVIT-MLKA model showed significant improvements in diagnostic accuracy and sensitivity compared to those without model assistance (P < 0.05). Grad-CAM visualization enhanced model interpretability by effectively highlighting key lesion areas.

CONCLUSION

The MVIT-MLKA model efficiently differentiates between benign and malignant pancreatic lesions, surpassing traditional methods and significantly improving radiologists' diagnostic performance. The integration of this advanced deep learning model into clinical practice has the potential to reduce diagnostic errors and optimize treatment strategies.

An integrated multi-omics biomarker approach using molecular profiling and microRNAs for evaluation of pancreatic cyst fluid

BACKGROUND

Classification and risk stratification of pancreatic cysts are challenging because of limited radiographic and cytomorphologic features. Although molecular profiling has emerged as an ancillary test for pancreatic cyst fluid (PCF), additional high-sensitivity and -specificity biomarkers are still needed for improved classification.

METHODS

In this study, PCF from 93 patients, including intraductal papillary mucinous neoplasms (n = 65), mucinous cystic neoplasms (n = 9), serous cystadenomas (n = 9), pancreatic cyst not otherwise specified (n = 8), and pseudocysts (n = 2), were evaluated for biomarkers. Molecular profiling by next-generation sequencing was performed, and a subset of the cases (n = 32) were interrogated with 2083 microRNAs (miRNAs) to evaluate their use for pancreatic cyst risk stratification.

RESULTS

As independent PCF biomarkers in 32 cases with histologic diagnoses, three miRNAs performed significantly better than mutant KRAS, mutant GNAS, carcinoembryonic antigen (CEA), and serum carbohydrate antigen 19-9 (CA19-9) in discriminating high-risk from low-risk cysts. The three elevated miRNAs in combination with mutant KRAS, mutant GNAS, and serum CA19-9 displayed similar diagnostic performance (miR-4461: area under the curve [AUC], 0.950; 95% confidence interval [CI], 0.800-1; miR-6723-5p: AUC, 0.958; 95% CI, 0.850-1; miR-6755-3p: AUC, 0.942; 95% CI, 0.816-1) in discriminating high-risk from low-risk cysts, when compared to mutant KRAS, mutant GNAS, CEA, and serum CA19-9 (AUC, 0.950; 95% CI, 0.825-1). In the absence of CA19-9, the three-marker panel of KRAS, GNAS, and miRNAs showed marginally improved performance compared with KRAS, GNAS, and CEA, which highlights the potential utility of miRNAs as biomarkers in PCF analysis.

CONCLUSIONS

These findings demonstrate that a multiomics biomarker approach with elevated PCF miRNAs with mutant KRAS, mutant GNAS, and serum CA19-9 may help in better detecting high-risk cysts for early clinical intervention.

Risk factors for pancreatic cancer in individuals with intraductal papillary mucinous neoplasms and no high-risk stigmata during up to 5 years of surveillance: a prospective longitudinal cohort study

BACKGROUND

Cyst size, its growth rate, and diameter of the main pancreatic duct (MPD) are all associated with pancreatic carcinoma prevalence in intraductal papillary mucinous neoplasms (IPMNs).

OBJECTIVE

To examine the above factors in relation to future risk of incident pancreatic carcinoma in individuals with IPMNs harbouring no high-risk stigmata.

DESIGN

In a prospective longitudinal cohort, we analysed 2549 patients with IPMNs. A multivariable cause-specific Cox proportional hazards regression model was built to estimate HRs for incident pancreatic carcinoma.

RESULTS

IPMN size at baseline and its annual growth rate over 2 years of follow-up were associated with incident pancreatic carcinoma (ptrend<0.001). The multivariable cause-specific HR per 10 mm increase in IPMN size was 1.28 (95% CI 1.10 to 1.50). The annual growth rates of 1.5-2.4 mm/year and ≥2.5 mm/year over 2 years were associated with multivariable cause-specific HRs of 1.91 (95% CI 0.78 to 4.67) and 4.52 (95% CI 2.28 to 8.98), respectively (vs <1.5 mm/year). Neither IPMN size at 5 years nor its maximum growth rate during 5 years was associated with incident pancreatic carcinoma (ptrend>0.07). MPD diameter at 5 years was associated with incident pancreatic carcinoma (multivariable cause-specific HR per 2 mm increase, 2.12; 95% CI 1.72 to 2.63). A predictive nomogram was generated for calculating the risk of incident pancreatic carcinoma.

CONCLUSION

IPMN size and its growth rate predict future pancreatic carcinoma risk only during first 5 years of follow-up. MPD diameter at 5 years may identify patients who still harbour a high risk for pancreatic carcinoma.

Endoscopic techniques for the diagnosis of pancreatic cystic lesions

Pancreatic cysts are mostly incidental findings on computed tomography or magnetic resonance imaging scans, with few patients presenting with abdominal pain or other symptoms. The accurate diagnosis of cysts is important as management depends on the type (neoplastic or non-neoplastic). Cross-sectional imaging is fast being replaced with endoscopic ultrasound (EUS) and various techniques based on that such as EUS-guided fine needle aspiration, EUS-guided needle confocal laser endomicroscopy, EUS-through-the-needle biopsy, and contrast-enhanced EUS. Clinical studies have reported varying diagnostic and adverse event rates with these modalities. In addition, American, European, and Kyoto guidelines for the diagnosis and management of pancreatic cysts have provided different recommendations. In this editorial, we elaborate on the clinical guidelines, recent studies, and comparison of different endoscopic methods for the diagnosis of pancreatic cysts.

Intracystic Glucose Measurement for On-Site Differentiation Between Mucinous and Non-Mucinous Pancreatic Cystic Lesions

BACKGROUND

Pancreatic cystic lesions (PCLs) are frequently detected incidentally and vary from benign to malignant. Accurate differentiation between mucinous (M-PCLs) and non-mucinous PCLs (NM-PCLs) is essential for appropriate management. This study aims to validate the accuracy of on-site glucose measurement using a glucometer with a cut-off of 50 mg/dL for distinguishing M-PCLs from NM-PCLs.

METHODS

In this prospective multicenter study, conducted at three European academic hospitals, patients who underwent endoscopic ultrasound-guided fine-needle aspiration for PCLs between 2019 and 2020 were included. On-site glucose measurement was performed using a conventional glucometer. Data on demographics, clinical features, EUS findings, and histopathology were collected.

RESULTS

Fifty patients were enrolled, with 37 having glucose levels < 50 mg/dL and 13 ≥ 50 mg/dL. M-PCLs were more common in the <50 mg/dL group (81%) compared to the ≥50 mg/dL group (23%, p < 0.001). The median CEA was higher in the <50 mg/dL group (146 ng/mL) than in the ≥50 mg/dL group (3 ng/mL, p = 0.047). On-site glucose testing < 50 mg/dl demonstrated a sensitivity of 93.2%, a specificity of 76.5%, and an accuracy of 89% for detecting M-PCLs with an AUC of 0.74 and an OR of 14.29 (p < 0.001). In comparison, CEA > 192 ng/mL had a sensitivity of 55.6%, a specificity of 87.5%, and an accuracy of 75.8% for M-PCLs, with an AUC of 0.65 and an OR of 4.44.

CONCLUSIONS

On-site glucose measurement using a glucometer with a cut-off of <50 mg/dL is a highly accurate, rapid, and cost-effective method for differentiating M-PCLs from NM-PCLs. Our results validate the glucose cut-off in a multicentric prospective cohort supporting its integration into standard diagnostic protocols for PCLs.

Next-generation sequencing improves diagnostic accuracy of imaging and carcinoembryonic antigen alone for pancreatic cystic neoplasms

BACKGROUND

New tools are needed to determine the pancreatic cysts that require surgical resection. This study aimed to evaluate whether next-generation sequencing (NGS) is useful for identifying mucinous, malignant, or pre-malignant cysts leading to surgery.

METHODS

Laboratory, cytological, and histological data from 97 patients with worrisome features on imaging or an unclear pancreatic cystic lesion (PCL) who were indicated for further investigation and who underwent endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) between 2018 and 2022 were analyzed. A multidisciplinary team evaluated MRI, CT, EUS-FNA, and NGS findings.

RESULTS

Among the 40 mucinous cysts, 53 % had KRAS and/or GNAS mutations, yielding a sensitivity of 53 % and specificity of 92 % compared to 33 and 100 % for cytology and 53 and 89 % for cystic fluid CEA. Combining NGS findings with CEA levels increased sensitivity and specificity in detecting mucinous lesions to 78 and 87 %, respectively. Surgically treated high-grade dysplasia PCLs did not show worrisome mutations in cyst fluid, while 80 % of the malignant lesions had mutations typical for advanced lesions. The advanced neoplasias showed 95 % specificity for worrisome gene mutations, with the highest diagnostic accuracy observed for NGS mutations, achieving an AUC of 0.777 in the ROC curve analysis compared to 0.631 for CEA. Patients with worrisome gene mutations were offered surgical treatment. NGS results contributed to the decision to operate in 11 out of 23 cases. In 71 % of all cases, NGS supported the diagnosis, with 3 % false positives and 12 % false negatives.

CONCLUSIONS

NGS analysis of pancreatic cyst fluid demonstrates high specificity and may serve as an additional diagnostic tool to CEA. Combining cystic fluid CEA and NGS increases the accuracy in determining whether a lesion is mucinous and NGS showed a higher diagnostic accuracy in advanced lesions compared to CEA. While the absence of alarming NGS findings should not preclude surgical treatment, patients with alarming mutations should be considered for surgery.

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

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

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.

Benign Etiology for High-Risk Intraductal Papillary Mucinous Neoplasm: A Case Report and Literature Review

Intraductal papillary mucinous neoplasms are relatively common and entail a variable risk of malignant potential. The Fukuoka guidelines present criteria for the risk of malignant transformation and are used for risk stratification and treatment decision-making. However, these guidelines entail some fallibility with limited sensitivity and specificity. In this case, we present an individual who had many of the hallmarks of malignant transformation but was found to have no evidence of malignancy or high-grade dysplasia. We discuss the suspected etiology of this individual's condition and how it might arise in others, as well as a brief review of the literature on risk factors in intraductal papillary mucinous neoplasms.