Solid-pseudopapillary neoplasm of the pancreas: Awareness of unusual clinical presentations and morphology of the clear cell variant can prevent diagnostic errors

Pancreatic solid pseudopapillary neoplasm, rare presentation in pediatric age group: two case reports

Solid pseudopapillary neoplasm (SPN) is a rare tumor that primarily affects young females. It is typically found in the pancreas and is often asymptomatic until it grows to a large size. SPN is more frequently located in the body or tail of the pancreas in adults, whereas in children, it is more commonly found in the head of the pancreas. In this report we present two female patients in the pediatric age group who were diagnosed with pancreatic SPN, each presenting with nonspecific symptoms, one with recurrent epigastric pain and nausea, the other with carpopedal spasms. Imaging showed large, cystic-solid pancreatic masses in both. Each case underwent a Whipple procedure (pancreaticoduodenectomy) with R0 resection. Pathology confirmed SPNs without lymphovascular or perineural invasion, and all surgical margins were clear. This series underscores SPN's varied presentations and favorable surgical outcomes in young adolescents. SPN is a rare neoplasm with low malignant potential that can present as a large abdominal mass. Although surgical resection is the treatment of choice, the optimal surgical approach remains controversial. Early detection and timely management are essential for a favorable outcome. Clinicians should consider SPN in the differential diagnosis of young females presenting with epigastric or pancreatic masses. This report highlights the importance of early detection and timely management of SPN.

A Unique Presentation of Solid Pseudopapillary Neoplasm of the Pancreas Requiring Pancreaticoduodenectomy Without Pancreatojejunostomy: A Case Report and Literature Review

Solid pseudopapillary neoplasms (SPNs) of the pancreas are rare tumors that predominantly affect young females and are typically located in the body and tail of the pancreas. Here, we present the case of a 59-year-old male with a large, heavily calcified SPN in the pancreatic head. His surgical history includes an aborted pancreaticoduodenectomy due to vascular involvement, followed by a gastrojejunostomy. Twenty years after the initial discovery, a pancreaticoduodenectomy was performed - the first of its kind - where the pancreas was completely atrophied, and no pancreaticojejunostomy was performed. Histological examination revealed typical features of SPN. This case demonstrates that even with relatively large lesions in a male patient over an extended duration, SPNs can still exhibit favorable features, highlighting the absence of specific preoperative markers for aggressive tumors. Therefore, unless there is an absolute contraindication, complete resection of all SPNs remains advisable.

Solid Pseudopapillary Neoplasm of the Pancreas: A Clinicopathological Study of 12 Cases With Emphasis on Diagnostic Pitfalls

INTRODUCTION

Solid pseudopapillary neoplasm of the pancreas (SPNP) is a rare primary neoplasm with distinct clinicopathological features. The tumor most commonly occurs in younger (premenopausal) women and is typified by low malignant potential and an excellent overall prognosis.

METHODS

A retrospective search over 20 years at two referral tertiary care institutions (King Faisal Hospital and Research Center and King Abdulaziz University Hospital, Jeddah, Kingdom of Saudi Arabia) revealed 12 female patients diagnosed with SPNPs. The reslts of ancillary studies performed at the time of diagnosis were also reviewed and placed in the context of current recommendations.

RESULTS

The clinical and pathological findings were reviewed. All patients were females, aged 18 to 30 years. Eight patients presented with abdominal pain, of which two experienced significant weight loss, and four presented with abdominal mass/discomfort. The tumor size ranged from 1.5 and 15 cm. Two cases were initially diagnosed as neuroendocrine tumors (NETs). One of the cases presented as a multifocal disease. All patients were treated surgically with a follow-up period between one and 11 years. Only one patient presented with peritoneal metastasis after seven years of follow-up, but generally, all are doing well.

CONCLUSIONS

We have analyzed 12 SPNP cases in our population over 20 years (2001-2021) in this study. In brief, SPNP is a low-grade malignant potential tumor. Even though SPNP is a recognized entity, diagnostic challenges can arise particularly in the setting of limited sampling. Pathologists must be aware of the classic morphological features of SPNP and the characteristic profile of immunohistochemistry and be able to differentiate SPNP from other mimickers, especially well-differentiated NETs of the pancreas, and ultimately to avoid misdiagnosis and unnecessary oncologic treatment. Adequate surgical resection with negative margins is associated with an excellent outcome.

Cytological Diagnosis of Pancreatic Solid-Pseudopapillary Neoplasm: A Single-Institution Community Practice Experience

Introduction. Pancreatic solid-pseudopapillary neoplasm (SPN) is a rare tumor that typically occurs in young females. Although a cytological diagnosis may be easily made in this age group when there are typical features, atypical clinical presentations and unusual cytological features may make this a challenging diagnosis. We present our single-institution experience in a cohort of these tumors, outlining both typical and atypical features. Awareness of unusual clinical and cytological features can help to avoid pitfalls during diagnosis. Methods. We performed a review of all cases of pancreatic SPNs diagnosed over a 15-year period (January 2007 to December 2021). Detailed cytological, clinical, and follow-up histological features were presented and analyzed. Results. Twenty-two cases of SPN were diagnosed at our institution during this 15-year period. Patients ranged from 12 to 73 years of age (mean 33 y, median 26 y) and included 19 females and 3 males. Seventeen patients had cytological material, and fourteen were diagnosed by EUS-FNA. Typical cytological features included papillary clusters with central capillaries, myxoid stroma, monomorphism, cercariform cells, and hyaline globules. Atypical or unusual cytological features that were seen in a few cases were multinucleated giant cells, clear cells, and/or foamy macrophages. A few cases showed features that were similar to pancreatic neuroendocrine tumors (PanNETs). Tumor cells were always positive for β-catenin, CD10, CD56, cyclin-D1, progesterone receptor (PR), and vimentin by immunohistochemistry. They were always negative for chromogranin. Pancytokeratin and synaptophysin stains were positive in 9% and 46% of cases evaluated, respectively. All cases had histological confirmation on resection. The median follow-up duration was 69 months (a range of 2–177 months), with only three cases lost to follow-up. No recurrence or metastasis was identified. Conclusions. We present our experience with cytological diagnoses of SPN in a well-characterized cohort of 22 patients with histological correlation and follow-up data. These tumors occur over a wide range and show varied cytological features. SPNs can be confidently diagnosed on limited cytological material, with limited panel immunohistochemistry aiding diagnosis in atypical cases. Recognizing the associated degenerative changes is crucial in avoiding a misdiagnosis.

Primary signet ring cell carcinoma of the pancreas: Cytopathology review of a rare entity

Primary signet ring cell carcinoma of the pancreas (PSRCCP) is an extremely rare diagnosis that has not been extensively studied in literature. Primary and metastatic neoplasms to the pancreas may exhibit cytomorphological similarities to signet ring cells, posing diagnostic challenges. In this article, we review PSRCCP and provide a study of several primary pancreatic neoplasms that may mimic the appearance of PSRCCP upon cytopathology evaluation, shedding light on the existence of this dilemma, and helping cytopathologists in navigating similar scenarios in their practice.

Role of Ancillary Testing on Endoscopic US-Guided Fine Needle Aspiration Samples from Cystic Pancreatic Neoplasms

Pancreatic cysts are increasingly detected on imaging studies. Accurate determination of the cyst type is important to provide appropriate care for the patients. It is also very clear that not one single modality can provide adequate diagnostic information. A multidisciplinary approach is the key to the diagnosis of pancreatic cysts. In this setting, the role of ancillary testing, which includes biochemical testing (carcinoembryonic antigen and amylase levels in the cyst), molecular testing (e.g., KRAS, GNAS, VHL, and CTNB1), and/or immunohistochemical tests are very important to obtain an accurate diagnosis. This review will discuss helpful ancillary tests in common pancreatic cyst neoplasms and how to approach the diagnosis of pancreatic cysts.

Comparison of the clinicopathological features of pancreatic solid pseudopapillary neoplasms between males and females: gender does matter

BACKGROUND

Solid pseudopapillary neoplasms (SPN) of the pancreas are a rare and low-grade malignant entity with a female predominance. However, it also occurs in males, but the rarity and lack of concern makes its clinicopathological features unclarified.

METHODS

The morphological, immunohistochemical, prognostic features and CTNNB1 exon 3 mutation status of SPN were compared semi-quantitively between 9 male and 21 female patients.

RESULTS

SPN in males grew in a distinctive solid pattern, with abundant fibrotic stroma and clear cells. Collagen tended to be the main component of tumor stroma in males, while hyaluronan composed a considerable proportion in females. A much stronger expression of androgen receptor (AR) was found in males, and CD56 and/or synaptophysin (Syn) was expressed frequently in both genders. All patients survived. One male patient had post-operational liver nodules and accepted interventional therapy without biopsy. Mutations of CTNNB1 exon 3 were observed in all cases, distributed at codon 32, 33 and 37 in both genders, as well as 34, 41 and 62 in females.

CONCLUSION

SPN in males presented with significantly different morphological features from that in females, which might be helpful in differential diagnosis, especially when with extensive positivity for CD56 and/or Syn. The stronger expression of AR in males might be a clue to explore the underlying mechanism of the gender difference.

Solid Pseudopapillary Neoplasm of the Pancreas: Analysis of Seven Cases

Background

The purpose of this study was to describe as well as compare our surgical treatment experiences of solid pseudopapillary neoplasms (SPN) of the pancreas and to provide a review of the literature.

Methods

A retrospective analysis of data from Vilnius University Hospital Santariskiu Klinikos (VUH SK) and of the literature, which was researched using Karger Publishers, Springer Science, BioMed Central, and disserCat databases, was conducted.

Results

From 2001 to 2012, seven cases were identified with pathologically confirmed SPN diagnosis. A precise preoperative diagnosis was made by computertomography and magnetic resonance imaging. The median diameter of the tumors was 6.36 cm (range 1.5-12 cm). Surgical treatment was undertaken for all patients. Results of the immunohistochemical analysis confirmed a nuclear accumulation of β-catenin. The Ki-67 level was 1-2% in all of the cases. According to our collected data, all types of histological analysis revealed decent prognostic behavior with low mitotic activity (1-2 mitoses per 50 high power fields). Besides, angioinvasion, perineural invasion, and outside capsule invasion were not detected.

Conclusions

There was no correlation between more aggressive types of SPN and tumor size, localization, age, and gender.

Clear cell variant of solid pseudopapillary neoplasm of pancreas diagnosed by fine needle aspiration: A case report and review of the literature

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare tumor of uncertain malignant potential, predominantly affecting young adult females. We report a case of clear cell variant of SPN, which was diagnosed by fine needle aspiration biopsy. The aspirate was highly cellular and exhibited delicate branching papillary structures with central capillaries covered with several layers of plasmacytoid tumor cells. Acinar and rosette-like formations, as well as single neoplastic cells were also observed. An unusual cytologic feature was the presence of large, clear cytoplasmic vacuoles. The diagnosis of SPN was confirmed by characteristic immunocytochemical staining pattern including nuclear staining for β-catenin, cytoplasmic staining for vimentin and lack of reactivity for cytokeratin.