Intraductal oncocytic papillary neoplasm of the pancreas: A systematic review

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.

Precision therapy for cancer prevention by targeting carcinogenesis

Cancer represents a major global public health burden, with new cases estimated to increase from 14 million in 2012 to 24 million by 2035. Primary prevention is an effective strategy to reduce the costs associated with cancer burden. For example, measures to ban tobacco consumption have dramatically decreased lung cancer incidence and vaccination against human papillomavirus can prevent cervical cancer development. Unfortunately, the etiological factors of many cancer types are not completely clear or are difficult to actively control; therefore, the primary prevention of such cancers is not practical. In this review, we update the progress on precision therapy by targeting the whole carcinogenesis process, especially for three high-risk groups: (1) those with chronic inflammation, (2) those with inherited germline mutations, and (3) those with precancerous lesions like polyps, gastritis, actinic keratosis or dysplasia. We believe that attenuating chronic inflammation, treating precancerous lesions, and removing high-risk tissues harboring germline mutations are precision methods for cancer prevention.

Cross-Sectional Imaging Characteristics of Pancreatic Intraductal Oncocytic Papillary Neoplasms

PURPOSE

Pancreatic intraductal oncocytic papillary neoplasms (IOPN) are rare precursors to pancreatic ductal adenocarcinoma. We report cross-sectional computed tomography and magnetic resonance imaging (where available) findings of pancreatic IOPNs.

MATERIALS AND METHODS

Consecutive cases of pancreatic IOPNs identified on pathology between 2008 and 2020 at University of Pittsburgh and Johns Hopkins University were included in the study. Cross-sectional imaging of all patients was reviewed by two subspecialty trained abdominal radiologists. Patient demographics, cross-sectional imaging appearances and growth characteristics were evaluated.

RESULTS

In this dual-center study, 14 patients with IOPNs were included. Median age was 64 years, and 64% were male. The median size of the lesions was 5.4 cm (range, 1.4-12.3 cm). All patients had either an enhancing mural nodule (93% of patients) and/or thick internal septations (29%). Thin/imperceptible outer wall was seen in 93%. Main duct was involved in 64% of the cases. Only 14% of the cases did not demonstrate abutment of the main duct. Histologic evaluation of surgical specimen showed high-grade dysplasia without invasive carcinoma in 57% and invasive carcinoma in 43% of cases. Lesions with invasive carcinoma were larger (7.1 cm vs 4.3 cm, P = 0.05) and tended to have larger mural nodule (3.7 cm vs 1.8 cm) compared with those without invasive carcinoma.

CONCLUSION

Pancreatic IOPNs are rare cystic premalignant lesions, which among resected cases, are predominantly seen in middle aged men, are often large, have enhancing mural nodules and frequently harbor invasive carcinoma.

Non-invasive intraductal oncocytic papillary neoplasm forming a protruding lesion toward the duodenum from the accessory papilla: a case report

BACKGROUND

Intraductal oncocytic papillary neoplasm (IOPN), previously classified as a subtype of intraductal papillary mucinous neoplasm (IPMN), has been described as an independent disease by the WHO since 2019. IOPN is a rare tumor, with few reported cases. Herein, we report a case of resected non-invasive IOPN that formed a lesion protruding toward the duodenum from the accessory papilla.

CASE PRESENTATION

An 80-year-old woman was referred to our hospital because of a giant mass in the pancreatic head detected on abdominal contrast-enhanced computed tomography (CT) performed for a close examination of a mass in the right breast. CT revealed a 90-mm-sized tumor with a mixture of solid and cystic components, with contrast enhancement in the pancreatic head, and a dilated main pancreatic duct. Esophagogastroduodenoscopy revealed a semi-circumferential papillary tumor protruding toward the duodenal lumen, which did not protrude from the papilla of Vater. Transpapillary biopsy led to a preoperative diagnosis of IPMN with an associated invasive carcinoma. As there were no distant metastasis, open subtotal stomach-preserving pancreaticoduodenectomy was performed. Analysis of the surgical specimen and histopathological examination revealed that the tumor was an IOPN that protruded toward the duodenal mucosa from the accessory papilla while replacing the duodenal mucosa with no obvious stromal invasion.

CONCLUSION

IOPN is a rare and poorly recognized tumor with few reported cases. There have been no reports describing IOPN forming a protruding lesion toward the duodenum from the accessory papilla. Therefore, further accumulation of cases such as this one is important to advance the study of IOPN.

Preoperatively diagnosed intraductal oncocytic papillary neoplasm of the pancreas with prominent invasion: a case report

Previously considered as one of the less-invasive subtypes of intraductal papillary mucinous neoplasm, intraductal oncocytic papillary neoplasm (IOPN) has recently been acknowledged as a new entity of pancreatic tumor. We herein present a case of preoperatively diagnosable IOPN invasion in the stomach and colon. A 78-year-old woman was referred to our hospital for evaluation of anorexia and gastroesophageal reflux. Upper gastrointestinal endoscopy revealed a gastric subepithelial lesion with ulcerated mucosa that required hemostasis. Computed tomography revealed a 96-mm-diameter solid tumor with a well-defined border and centrally positioned necrotic area, extending from the stomach to the transverse colon and pancreatic tail. Because it was suspected to be a pancreatic solid tumor with direct stomach invasion, endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) was performed, which led to a preoperative diagnosis of IOPN. Moreover, laparoscopic pancreatosplenectomy, proximal gastrectomy, and transverse colectomy were performed. Analysis of the surgical specimen revealed that the tumor was IOPN and had invaded the stomach and transverse colon. Lymph node metastasis was also confirmed. These findings indicate that IOPN can manifest as an invasive tumor, and EUS-FNB may be equally helpful for assessing the invaded area of a cystic lesion as it is for a solid lesion.

Intraductal oncocytic papillary neoplasm of the pancreas: clinical and radiological features compared to those of intraductal papillary mucinous neoplasm

PURPOSE

This study aimed to characterize the clinical and imaging findings of intraductal oncocytic papillary neoplasm of the pancreas (IOPN-P) compared to those of intraductal papillary mucinous adenoma/carcinoma (IPMA/IPMC).

METHODS

This multi-institutional retrospective study reviewed the clinical, imaging, and pathological findings of 21 patients with pathologically proven IOPN-P. Twenty-one computed tomography (CT) and magnetic resonance imaging, and seven 18F-fluorodeoxyglucose (FDG)-positron emission tomography were performed before surgery. The following findings were evaluated: preoperative blood test results, lesion size and location, pancreatic duct diameter, contrast-enhancement effect, bile duct and peripancreatic invasion, maximum standardized uptake (SUVmax) value, and pathological stromal invasion.

RESULTS

Serum carcinoembryonic antigen (CEA) and cancer antigen 19-9 (CA19-9) levels were significantly higher in the IPMN/IPMC group than in the IOPN-P group. Except in one patient, IOPN-P showed multifocal cystic lesions with solid components or a tumor in the main pancreatic duct (MPD) with dilatation. IOPN-P had a higher frequency of solid parts and a lower frequency of downstream MPD dilatation than IPMA. IPMC showed smaller overall cyst size, more radiological peripancreatic invasion, and worse recurrence-free and overall survival than IOPN-P. The average SUVmax value of IOPN-P was 7.5. Pathologically, 17 of the 21 IOPN-Ps had a malignant component, and six showed stromal invasion.

CONCLUSION

IOPN-P shows cystic-solid lesions similar to IPMC but has lower serum CEA and CA19-9 levels, larger overall cyst size, lower frequency of peripancreatic invasion, and more favorable prognosis than IPMC. Moreover, the high FDG uptake by IOPN-Ps may be a characteristic finding of this study.

Analyzing and predicting the LNM rate and prognosis of patients with intraductal papillary mucinous neoplasm of the pancreas

Background

Current the surveillance and management are controversial for patients with IPMN. We aimed to develop an alternative nomogram to individualize IPMN prognosis and LNM.

Methods

Based on the data from SEER database of patients diagnosed with IPMN between 2004 and 2015, a nomogram predicting the survival and LNM of IPMN based on univariate and multivariate and Lasso regression analysis was performed, internally and externally validated, and measured by C‐index, and decision curve analysis (DCA), and compared to the 7^th TNM stage.

Results

A total of 941 patients were included. Age, T stage examined nodes, tumor size, and pathology grade were identified as an independent factor for predicting LNM. The nomogram we established to predict LNM had a high predicting value with a C‐index value of 0.735 and an AUC value of 0.753. Interestingly, including T1 stage, we found an inverse correlation was between age and LNM. In addition, nomogram for predicting CSS also performed better than TNM stage both in the internal validation group (1‐year AUC:0.753 vs. 0.693, 3‐year AUC: 0.801 vs. 0.731, 5‐year AUC: 0.803 vs. 0.733) and external validation group (1‐year AUC: 0.761 vs. 0.701, 3‐year AUC: 0.772 vs. 0.713, 5‐year AUC:0.811 vs. 0.735). DCA analysis showed the nomogram showed a greater benefit across the period of follow‐up compared to 7^th TNM stage.

Conclusion

A nomogram based on multivariate and Lasso regression analysis showed great clinical usability compared with current criteria. Also, for LNM of IPMN, younger age patients with IPMN should be attached more importance.