International external validation of a stratification tool to identify branch-duct intraductal papillary mucinous neoplasms at lowest risk of progression

Association of Smoking with progression from low-risk to high-risk intraductal papillary mucinous neoplasms and pancreatic cancer

BACKGROUND

Factors associated with the risk of pancreatic adenocarcinoma (PDAC) may play a role in the development and progression of Intraductal Papillary Mucinous Neoplasms (IPMNs). However, data are limited.

AIM

To compare exposome factors in three groups of patients with "high or low-risk" IPMNs, as assessed at diagnosis and during a 24-months follow-up, and with PDAC.

METHODS

Patients were matched (same sex, age ±5) 1:1. Exposure variables were compared across groups using Kruskal-Wallis, ANOVA, or Chi-square tests with Bonferroni correction.

RESULTS

A total of 151 patients were enrolled in each of the three groups (453 overall). The proportion of current smokers was progressively higher in "low-risk", "high-risk" IPMNs and PDAC patients (8.1 %, 11.2 %, 23.3 %; p = 0.0002). The three groups did not differ in terms of ever or heavy smoking, BMI, history of diabetes, cancer, cholecystectomy or chronic pancreatitis, use of statins or aspirin, and family history of cancer. A history of peptic ulcer was more common in PDAC (7.2 %) than in either "low-risk" (2.0 %) or "high-risk" (2.6%) IPMNs (p = 0.02, not significant after Bonferroni correction).

CONCLUSION

Active smoking seems associated with the progression of IPMNs to malignancy, and cessation of active smoking might be advised in patients with IPMN.

The role of endoscopic ultrasound in the detection of pancreatic lesions in high-risk individuals

Individuals at high risk of developing pancreatic ductal adenocarcinoma are eligible for surveillance within research programs. These programs employ periodic imaging in the form of magnetic resonance imaging/magnetic resonance cholangiopancreatography or endoscopic ultrasound for the detection of early cancer or high-grade precursor lesions. This narrative review discusses the role of endoscopic ultrasound within these surveillance programs. It details its overall strengths and limitations, yield, burden on patients, and how it compares to magnetic resonance imaging. Finally, recommendations are given when and how to incorporate endoscopic ultrasound in the surveillance of high-risk individuals.

Risk Perceptions and Risk Thresholds Among Surgeons in the Management of Intraductal Papillary Mucinous Neoplasms

OBJECTIVES

We aimed to determine whether surgeon variation in management of intraductal papillary mucinous neoplasm (IPMN) is driven by differences in risk perception and quantify surgeons' risk threshold for changing their recommendations.

BACKGROUND

Surgeons vary widely in management of IPMN.

METHODS

We conducted a survey of members of the Americas HepatoPancreatoBiliary Association, presented participants with 2 detailed clinical vignettes and asked them to choose between surgical resection and surveillance. We also asked them to judge the likelihood that the IPMN harbors cancer and that the patient would have a serious complication if surgery was performed. Finally, we asked surgeons to rate the level of cancer risk at which they would change their treatment recommendation. We examined the association between surgeons' treatment recommendations and their risk perception and risk threshold.

RESULTS

One hundred fifty surgeons participated in the study. Surgeons varied in their recommendations for surgery [19% for vignette 1 (V1) and 12% for V2] and in their perception of the cancer risk (interquartile range: 2%-10% for V1 and V2) and risk of surgical complications (V1 interquartile range: 10%-20%, V2 20-30%). After adjusting for surgeon characteristics, surgeons who were above the median in cancer risk perception were 22 percentage points (27% vs 5%) more likely to recommend resection than those who were below the median (95% CI: 11%-4%; P <0.001). The median risk threshold at which surgeons would change their recommendation was 15% (V1 and V2). Surgeons who recommended surgery had a lower risk threshold for changing their recommendation than those who recommended surveillance (V1: 10.0 vs 15.0, P =0.06; V2: 7.0 vs 15.0, P =0.05).

CONCLUSIONS

The treatment that patients receive for IPMNs depends greatly on how their surgeons perceive the risk of cancer in the lesion. Efforts to improve cancer risk prediction for IPMNs may lead to decreased variations in care.

Role of pancreatic ductal adenocarcinoma risk factors in intraductal papillary mucinous neoplasm progression

Introduction

Pancreatic ductal adenocarcinoma (PDAC) is lethal due to its late diagnosis and lack of successful treatments. A possible strategy to reduce its death burden is prevention. Intraductal papillary mucinous neoplasms (IPMNs) are precursors of PDAC. It is difficult to estimate the incidence of IPMNs because they are asymptomatic. Two recent studies reported pancreatic cysts in 3% and 13% of scanned subjects. The possibility of identifying a subgroup of IPMN patients with a higher probability of progression into cancer could be instrumental in increasing the survival rate. In this study, genetic and non-genetic PDAC risk factors were tested in a group of IPMN patients under surveillance.

Methods

A retrospective study was conducted on 354 IPMN patients enrolled in two Italian centres with an average follow-up of 64 months. With the use of DNA extracted from blood, collected at IPMN diagnosis, all patients were genotyped for 30 known PDAC risk loci. The polymorphisms were analysed individually and grouped in an unweighted polygenic score (PGS) in relation to IPMN progression. The ABO blood group and non-genetic PDAC risk factors were also analysed. IPMN progression was defined based on the development of worrisome features and/or high-risk stigmata during follow-up.

Results

Two genetic variants (rs1517037 and rs10094872) showed suggestive associations with an increment of IPMN progression. After correction for multiple testing, using the Bonferroni correction, none of the variants showed a statistically significant association. However, associations were observed for the non-genetic variables, such as smoking status, comparing heavy smokers with light smokers (HR = 3.81, 95% 1.43-10.09, p = 0.007), and obesity (HR = 2.46, 95% CI 1.22-4.95, p = 0.012).

Conclusion

In conclusion, this study is the first attempt to investigate the presence of shared genetic background between PDAC risk and IPMN progression; however, the results suggest that the 30 established PDAC susceptibility polymorphisms are not associated with clinical IPMN progression in a sample of 354 patients. However, we observed indications of cigarette smoking and body mass index (BMI) involvement in IPMN progression. The biological mechanism that could link these two risk factors to progression could be chronic inflammation, of which both smoking and obesity are strong promoters.

Modern aspects of the management of pancreatic intraductal papillary mucinous neoplasms: a narrative review

Intraductal papillary mucinous neoplasms (IPMNs) account for approximately 35% of all cystic tumors in the pancreas and represent the largest subgroup. They are characterized by mucin production and intraductal papillary epithelium growth. IPMNs range from benign to malignant lesions. Biomarkers combined with 18F-Fluorodeoxyglucose-positron emission tomography (18FDG-PET) is the best diagnostic tool. The risk of malignant transformation for main-duct IPMNs is between 34-68% and for low-risk branch-duct (BD)-IPMNs it is 1.1%. Monitoring is crucial for determining the optimal time of surgical excision. Novel artificial intelligence combining clinical, tumor biomarkers, imaging and molecular genomics plays a determinant role in the evaluation of such lesions. The first diagnostic tool is multidetector helical computed tomography (MDHCT) or up-to-date magnetic resonance imaging (MRI). MRI detects malignancy by enhancing mural nodules ≥3 mm. Novel endosonographic interventional techniques have been added to the diagnostic armamentarium. Pancreatoscopy is feasible and effective but challenging for evaluating the diagnosis, invasiveness, and extent of IPMNs. Its findings may change the surgical approach. Pancreatic juice and duodenal fluid have been used recently for molecular biological analysis. The genes most frequently altered include Kirsten rat sarcoma viral proto-oncogene (KRAS), tumor protein p53 (TP53), cyclin-dependent kinase inhibitor 2A (CDKN2A), SMAD family member 4 (SMAD4), and guanine nucleotide-binding protein, alpha stimulating (GNAS). Despite the advances in diagnostic modalities, assessment of this premalignant lesion of pancreatic cancer, with its poor prognosis, is a challenging task. Pancreatectomy is the indicated approach for malignant or high-risk IPMNs with potent malignancy. Conservative management or enucleation for preserving the pancreas of low-risk BD-IPMNs is recommended, but long-term follow-up for recurrence is necessary. The management of IPMNs must be individualized based on preoperative high-risk stigmata and worrisome features.