Pancreatic juice cytology as sensitive test for detecting pancreatic malignancy in intraductal papillary mucinous neoplasm of the pancreas without mural nodule

Early detection of pancreatic cancer

The diagnosis of pancreatic cancer associates an appalling significance. Detection of preinvasive stage of pancreatic cancer will ameliorate the survival of this deadly disease. Premalignant lesions such as Intraductal Papillary Mucinous Neoplasms or Mucinous Cystic Neoplasms of the pancreas are detectable on imaging exams and this permits their management prior their invasive development. Pancreatic intraepithelial neoplasms (PanIN) are the most frequent precursors of pancreatic adenocarcinoma (PDAC), and its particular type PanIN high-grade represents the malignant non-invasive form of PDAC. Unfortunately, PanINs are not detectable on radiologic exams. Nevertheless, they can associate indirect imaging signs which would rise the diagnostic suspicion. When this suspicion is established, the patient will be enrolled in a follow-up strategy that includes performing of blood test and serial imaging test such as computed tomography or magnetic resonance imaging, which will cost in the best-case scenario a burden of healthcare systems, and potential mortality in the worst-case scenario when the patient underwent resection surgery, worthless when there is no moderate or high grade dysplasia in the final histopathology. This issue will be avoid having at its disposal a diagnostic technique capable of detecting high-grade PanIN lesions, such is the cytology of pancreatic juice obtained by nasopancreatic intubation. Herein, we review the possibility of detection of early malignant lesions before they become invasive PADC.

Value of repeated cytology for intraductal papillary mucinous neoplasms of the pancreas with high risk potential of malignancy: Is it a promising method for monitoring a malignant transformation?

OBJECTIVES

The efficacy of and indications for cytological reexamination to detect malignant changes in branch duct type intraductal papillary mucinous neoplasms (BD-IPMNs) have not been studied in detail. We conducted a retrospective study to evaluate the efficacy and indications of cytological reexamination by using pancreatic juice (repeated cytology) for BD-IPMNs.

METHODS

Forty-five patients who underwent repeated cytology after a diagnosis of benignancy by using initial cytology were recruited for this study.

RESULTS

Thirty-eight patients, excluding 7 patients with lack of surveillance period after the final cytology, were classified into Malignancy (n = 13) and Benignancy groups (n = 25) on the bases of the findings from resected specimens or changes in BD-IPMNs after repeated cytology. The sensitivity and specificity to detect malignant changes in BD-IPMNs by using repeated cytology were 62% and 100%, respectively. For the 12 patients with mural nodules (MNs) ≥ 5 mm (67% of them were malignant), the sensitivity was 50%, whereas, for the 26 patients without MNs ≥ 5 mm (19% of them were malignant), it was 80%. In addition, malignant changes in BD-IPMNs after initial cytology occurred in 62% of the patients with changes in the MNs and 27% of the patients with an increase in the cyst size.

CONCLUSION

Repeated cytology can play a role in the determination for surgery even after a diagnosis of benignancy by using initial cytology, especially for BD-IPMNs without MNs ≥5 mm. In addition, changes in the MNs or cyst size may be appropriate indications for repeated cytology.

Surgical indication for intraductal papillary mucinous neoplasm without mural nodule ≥5 mm

BACKGROUND

In intraductal papillary mucinous neoplasm, a mural nodule ≥5 mm is an important predictor of malignancy. Surgical indication is less clear in cases of intraductal papillary mucinous neoplasm without mural nodule ≥5 mm. This is a retrospective study evaluating predictors of high-grade dysplasia or invasive intraductal papillary mucinous carcinoma for intraductal papillary mucinous neoplasm without mural nodule ≥5 mm.

METHODS

Among consecutive patients who underwent surgery for intraductal papillary mucinous neoplasm between 1999 and 2018, 174 had intraductal papillary mucinous neoplasm with mural nodule ≥5 mm (mural nodule[+] ≥5 mm group). The remaining 155 patients had intraductal papillary mucinous neoplasm but did not have mural nodule ≥5 mm: 24 patients with mural nodule <5 mm (mural nodule[+] <5 mm group) and 131 patients without mural nodule (mural nodule[-] group). We investigated predictors of high-grade dysplasia or invasive intraductal papillary mucinous neoplasm in cases of intraductal papillary mucinous neoplasm without mural nodule ≥5 mm.

RESULTS

The frequency of high-grade dysplasia invasive intraductal papillary mucinous neoplasm was significantly higher in the mural nodule(+) ≥5 mm group (87.4%) than in the mural nodule(+) <5 mm group (37.5%, P < .001) and mural nodule(-) group (45.0%, P < .001). However, frequency was not significantly different between mural nodule(+) <5 mm and mural nodule(-) groups (P = .494). Multivariate analysis showed three independent predictors of high-grade dysplasia invasive intraductal papillary mucinous carcinoma in intraductal papillary mucinous neoplasm without mural nodule ≥5 mm: branch cyst ≥40 mm (P = .038, odds ratio 3.704; 95% confidence interval, 1.075-12.821), positive cytology of pancreatic juice (P = .039, odds ratio 16.792; 95% confidence interval, 1.152-244.744), and carcinoembryonic antigen in pancreatic juice ≥30 mg/mL (P < .001, odds ratio 14.925; 95% confidence interval, 4.525-50.0).

CONCLUSION

For cases of intraductal papillary mucinous neoplasm without mural nodule ≥5 mm, large cysts, positive cytology of the pancreatic juice, and high levels of carcinoembryonic antigen in pancreatic juice may be useful to determine surgical indication, although further studies are needed to confirm these results.

The role of pancreatic juice cytology in the diagnosis of pancreatic intraductal papillary mucinous neoplasm

BACKGROUND AND AIM

pancreatic juice cytology (PJC) is an important predictor of malignant intraductal papillary mucinous neoplasm (IPMN). This study aimed to determine the role of PJC for the prediction of malignant IPMN (intraductal papillary mucinous cancer [IPMC]).

METHODS

medical records of IPMN patients who underwent surgery between 2012 and 2016 at the Nagasaki University Hospital were reviewed. Patients who underwent preoperative PJC were classified as high risk stigmata (HRS), worrisome features (WF) and no-criteria, based on imaging criteria. PJC class III or higher was considered as positive and only invasive IPMN was defined as IPMC. PJC was validated in each group with regard to sensitivity, specificity, accuracy with the corresponding 95% confidence intervals (95% CI) and area under receiver operating curve (AUROC) analysis. A p-value of < 0.05 was considered as statistically significant.

RESULTS

preoperative pancreatic juice was obtained in 33/52 IPMN patients; only patients with adequate aspirate for cytology (n = 29) were included. In the HRS group (n = 9), 4/6 non-IPMC had a negative PJC and 3/3 IPMC had a positive PJC. In the WF group (n = 17), 9/11 non-IPMC had a negative PJC and 3/6 IPMC had a positive PJC. Adding PJC to imaging results improved the AUROCs of HRS and WF from 0.63 and 0.62 to 0.83 and 0.66, respectively. PJC was negative in all no-criteria cases (n = 3; one IPMC and two non-IPMC). In all 29 patients, PJC sensitivity was 60% (95% CI: 26%-88%), specificity was 79% (95% CI: 54%-94%), accuracy was 72% (95% CI: 63%-89%) and the AUROC was 0.69 (p = 0.03).

CONCLUSION

PJC is a statistically significant IPMC predictor that can improve the validity of imaging for IPMC prediction.

Genomic analysis of pancreatic juice DNA assesses malignant risk of intraductal papillary mucinous neoplasm of pancreas

Intraductal papillary mucinous neoplasm (IPMN) of pancreas has a high risk to develop into invasive cancer or co‐occur with malignant lesion. Therefore, it is important to assess its malignant risk by less‐invasive approach. Pancreatic juice cell‐free DNA (PJD) would be an ideal material in this purpose, but genetic biomarkers for predicting malignant risk from PJD are not yet established. We here performed deep exome sequencing analysis of PJD from 39 IPMN patients with or without malignant lesion. Somatic alterations and copy number alterations (CNAs) detected in PJD were compared with the histologic grade of IPMN to evaluate their potential as a malignancy marker. Somatic mutations of KRAS, GNAS, TP53, and RNF43 were commonly detected in PJD of IPMNs, but no association with the histologic grades of IPMN was found. Instead, mutation burden was positively correlated with the histologic grade (r = 0.427, P = 0.015). We also observed frequent copy number deletions in 17p13 (TP53) and amplifications in 7q21 and 8q24 (MYC) in PJDs. The amplifications in 7q21 and 8q24 were positively correlated with the histologic grade and most prevalent in the cases of invasive carcinoma (P = 0.002 and 7/11; P = 0.011 and 6/11, respectively). We concluded that mutation burden and CNAs detected in PJD may have potential to assess the malignant progression risk of IPMNs.

Evaluation of efficacy of pancreatic juice cytology for risk classification according to international consensus guidelines in patients with intraductal papillary mucinous neoplasm; a retrospective study

OBJECTIVES

Pancreatic juice cytology (PJC) for intraductal papillary mucinous neoplasm (IPMN) is a possible tool to enhance preoperative diagnostic ability by improving risk classification for malignant IPMN, but its efficacy is controversial. This study evaluated the efficacy of PJC for risk classification according to international guidelines.

METHODS

We retrospectively analyzed 127 IPMN patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) preoperatively. PJC was performed in 125 of the 127 cases. High-risk stigmata (HRS, n = 57), worrisome features (WF, n = 64), and other characteristics (n = 6) were classified according to the 2017 international guidelines.

RESULTS

Among the 127 IPMN patients, 71 (55.9%) had malignant IPMN (invasive and non-invasive intraductal papillary mucinous carcinoma). The accuracy of WF for classifying malignant IPMN was increased by the addition of PJC, but the accuracy of HRS was not (WF to WF + PJC: 33.1% [42/127] to 48.8% [61/125], HRS to HRS + PJC: 65.4% [83/127] to 52.8% [66/125]). Post-ERCP pancreatitis (PEP) occurred in 32 (25.2%) of 127 IPMN patients. Severe PEP was not detected. Significant risk factors for PEP were female sex, obesity, and endoscopic naso-pancreatic drainage (ENPD) (P = .03, P = .0006, and P = .02, respectively). In patients with ENPD tube placement, a main pancreatic duct size of <5 mm was a significant risk factor for PEP (P = .02).

CONCLUSION

PJC could increase the accuracy of WF for classifying malignant IPMN. The additive effect of PJC for risk classification may be limited, however, and it is not recommended for all IPMN cases due to the high frequency of PEP.

Endoscopic diagnosis of cystic lesions of the pancreas

Endoscopic methods are increasingly used in the diagnosis of cystic lesions of the pancreas. The two major endoscopic approaches are endoscopic ultrasonography (EUS) and transpapillary diagnosis. EUS-guided fine-needle aspiration cytology and EUS-guided fine needle-based confocal laser endomicroscopy have been used in the differential diagnosis of mucinous and non-mucinous pancreatic cysts. EUS is the most sensitive modality for detecting mural nodules (MN) in intraductal papillary mucinous neoplasms (IPMN). Contrast-enhanced harmonic EUS (CH-EUS), as an add-on to EUS, is useful for identifying and characterizing MN. Recent studies show that CH-EUS has a sensitivity of 60-100% and a specificity of 75-92.9% for diagnosing malignant cysts. Intraductal ultrasonography and peroral pancreatoscopy are especially useful for detecting MN and IPMN. A recent meta-analysis showed that cytological assessment of pancreatic juice using a transpapillary approach had a pooled sensitivity, specificity, and accuracy of 35.1%, 97.2%, and 92.9%, respectively, for diagnosing malignant IPMN. Further studies are warranted to determine the indications for each of these novel techniques in assessing cystic lesions of the pancreas.