Comprehensive Characterization of Intraductal Oncocytic Papillary Neoplasm of the Pancreas: A Systematic and Critical Review

Rare pancreatic cystic neoplasms: A pictorial review

Since rare pancreatic cystic tumors may differ from common pancreatic cystic neoplasms in terms of treatment plan and prognosis, the differential diagnosis of these diseases is clinically relevant. Various imaging tests play an important role in the differential diagnosis of rare cystic pancreatic tumors, but accurately distinguishing these diseases solely on the basis of imaging findings is challenging. The purpose of this pictorial review is to present CT and in particular MR imaging features of rare pancreatic cystic tumors and discuss potential elements for differential diagnosis.

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.

Laparoscopic management of intraductal oncocytic papillary neoplasm of the pancreas: Two case reports and review of literature

BACKGROUND

Intraductal oncocytic papillary neoplasm (IOPN) of the pancreas is an extremely rare pancreatic tumor, with only sporadic cases reported in the literature. IOPN is difficult to diagnose and highly prone to misdiagnosis. IOPN carries a certain risk of progressing to invasive cancer. Surgical resection is the primary treatment for IOPN. According to the existing literature reports, the vast majority of patients with IOPN of the pancreas undergo open surgery, while only one case of laparoscopic surgery have been reported.

CASE SUMMARY

This report presents two cases of IOPN in elderly female patients, aged 60 and 61. Both patients were asymptomatic, and their pancreatic masses were discovered incidentally. Preoperative diagnosis of IOPN is challenging and prone to misdiagnosis. In the first case, the patient underwent a laparoscopic distal pancreatectomy and splenectomy. The surgical procedure spanned 342 minutes, with an estimated intraoperative blood loss of around 100 mL. The patient experienced an uneventful postoperative recovery and was discharged on the 8th postoperative day. For the second case, a laparoscopic pancreaticoduodenectomy was performed. The operation lasted for 431 minutes with an intraoperative blood loss of approximately 50 mL. The patient also demonstrated a favorable postoperative course and was discharged on the 24th postoperative day. Postoperative pathology and immunohistochemistry confirmed the diagnosis of IOPN. No recurrence was observed in either patient after follow-up periods of 8 and 10 months, respectively.

CONCLUSION

These cases demonstrate that laparoscopic surgery can be considered as one of the treatment options for IOPN of the pancreas.