Solid pseudopapillary neoplasm of the pancreas—proposed algorithms for diagnosis and surgical treatment

Solid pseudopapillary tumor of pancreas: A report of two cases and literature review

Solid pseudopapillary neoplasm of the pancreas is rarely encountered in clinical practice. It is a tumor with a good prognosis and overall curative rates. It primarily affects young females in their twenties. It has characteristic imaging appearances, but a definite diagnosis requires histopathological examination. The treatment goal of solid pseudopapillary neoplasm is almost always curative and aims for complete resection of the mass. Here, we present 2 cases of this rare neoplasm. The first case was managed by laparoscopic distal pancreatectomy, while the second underwent a Whipple procedure for pancreatic head involvement.

Twenty-one years of experience with resected solid pseudopapillary neoplasm: a retrospective single-institutional cohort study

BACKGROUND

Although the incidence of solid pseudopapillary neoplasm (SPN) is <2% of the incidence of pancreatic tumor, the prevalence seems to be increasing. SPNs are mostly benign. However, they also show malignant features. This study aimed to identify the clinical outcomes of patients who underwent surgery for SPN at a single center.

METHODS

Data on 217 patients with SPN who underwent surgery in Samsung Medical Center between 2000 and 2020 were retrospectively analyzed.

RESULTS

Herein, the mean age of the 217 patients was 40.0 ± 12.6 years, with a female predominance (80.6%). Most patients had no comorbidity. The mean tumor size was 4.4 ± 3.1 cm. The tumor was located at the pancreatic head in 36 patients (16.6%), the body of the pancreas in 69 patients (31.8%), and the pancreatic tail in 96 patients (44.2%). Of note, 35 patients (16.1%) underwent pancreaticoduodenectomies, 148 patients (68.2%) had distal pancreatectomies, and the other patients had subtotal /total pancreatectomy (9.7%) or enucleation/mass excision (6.0%). No patient had lymph node (LN) metastasis. Moreover, 6 patients (2.8%) had a recurrence in the liver or regional LNs. The 5-year recurrence-free survival rate was 96.8%. The only factor affecting recurrence was tumor size (P = .007).

CONCLUSION

Because SPN predominates in relatively young women, patients often hesitate to undergo surgery. Nevertheless, as size is the prognostic factor, early resection is recommended for a better prognosis in the case of surgically feasible, young age, and healthy patients.

Solid pseudopapillary neoplasm of the pancreas: A case report with a brief literature review

INTRODUCTION

Solid pseudopapillary neoplasm (SPN) of the pancreas, representing only 1 % of pancreatic cancers, was identified by Virginia Frantz in 1959. Predominantly affecting young females, it often remains asymptomatic, posing diagnostic challenges due to slow growth. This paper emphasizes SPN's rarity and associated diagnostic complexities.

CASE PRESENTATION

In a specific case, a 17-year-old female with post-traumatic right flank pain underwent an enhanced CT scan, revealing a well-defined, hypodense mass in the pancreatic head. With normal laboratory results, a diagnostic laparotomy exposed a sizable solid cystic mass. A Whipple procedure unveiled a predominantly cystic mass enveloped by a well-developed capsule.

DISCUSSION

SPN appears as a distinct mixed solid and cystic lesion on imaging, necessitating confirmation through core biopsy. Surgical resection, the primary treatment, ensures a positive overall prognosis, despite rare recurrence and metastases. Microscopic examination reveals pseudopapillae, and immunohistochemistry aids diagnosis with positive staining for estrogen receptor, progesterone receptor, CD10, and CD99.

CONCLUSION

SPN, a rare pancreatic neoplasm predominantly affecting young females, may present with abdominal pain or palpable mass despite its usual asymptomatic nature. Diagnosis involves imaging and biopsy confirmation, with surgical resection as the curative treatment. While prognosis is generally favorable, comprehensive understanding and improved management require further research for this uncommon pancreatic neoplasm.

Malignant Solid Pseudopapillary Neoplasm of the Pancreas: An Orthogonal Analysis

BACKGROUND

Pancreatic solid pseudopapillary neoplasms (SPN) are generally indolent; however, some patients present with "malignant" SPN. An orthogonal analysis of multiple datasets was performed to investigate the utility of complete surgical resection (CSR) for malignant SPN.

METHODS

A systematic review was performed for cases of malignant SPN, defined as T4, N1, and/or M1. Malignant SPN was analyzed within the National Cancer Database (NCDB) and compared with T1-3N0M0 SPN. Predictors of malignant SPN were assessed, and treatments were analyzed by using survival analysis.

RESULTS

The systematic review yielded 164 cases of malignant SPN. Of 31 children, only one died due to malignant SPN. Among adults, CSR was associated with improved disease-specific survival (DSS) (P = 0.0002). Chemotherapy did not improve malignant SPN DSS, whether resected (P = 0.8485) or not (P = 0.2219). Of 692 adults with SPN within the NCDB, 93 (13.4%) had malignant SPN. Pancreatic head location (odds ratio [OR] 2.174; 95% confidence interval [CI] 1.136-4.166; P = 0.0186) and tumor size (OR 1.154; 95% CI 1.079-1.235; P < 0.0001) associated with the malignant phenotype. Malignant SPN predicted decreased overall survival (OS) compared with T1-3N0M0 disease (P < 0.0001). Resected malignant SPN demonstrated improved OS (P < 0.0001), including resected stage IV malignant SPN (P = 0.0003). Chemotherapy did not improve OS for malignant SPN, whether resected (P = 0.8633) or not (P = 0.5734). Within a multivariable model, resection was associated with decreased hazard of death (hazard ratio 0.090; 95% CI 0.030-0.261; P < 0.0001).

CONCLUSIONS

Approximately 13% of patients with SPN present with a malignant phenotype. Pediatric cases may be less aggressive. Resection may improve survival for malignant SPN, which does not appear chemosensitive.

Potential Role for Observation in Small Solid Pseudopapillary Neoplasm (SPN)

BACKGROUND

Solid pseudopapillary neoplasms (SPN) are rare tumors of the pancreas, typically affecting young women. Resection is the mainstay of treatment but is associated with significant morbidity and potential mortality. We explore the idea that small, localized SPN could be safely observed.

METHODS

This retrospective review of the Pancreas National Cancer Database from 2004 to 2018 identified SPN via histology code 8452.

RESULTS

A total of 994 SPNs were identified. Mean age was 36.8 ± 0.5 years, 84.9% (n = 844) were female, and most had a Charlson-Deyo Comorbidity Coefficient (CDCC) of 0-1 (96.6%, n = 960). Patients were most often staged clinically as cT2 (69.5%, n = 457) followed by cT3 (17.6%, n = 116), cT1 (11.2%, n = 74), and cT4 (1.7%, n = 11). Clinical lymph node and distant metastasis rates were 3.0 and 4.0%, respectively. Surgical resection was performed in 96.6% of patients (n = 960), most commonly partial pancreatectomy (44.3%) followed by pancreatoduodenectomy (31.3%) and total pancreatectomy (8.1%). In patients clinically staged as node (N0) and distant metastasis (M0) negative, occult pathologic lymph node involvement was found in 0% (n = 28) of patients with stage cT1 and 0.5% (n = 185) of patients with cT2 disease. The risk of occult nodal metastasis significantly increased to 8.9% (n = 61) for patients with cT3 disease. The risk further increased to 50% (n = 2) in patients with cT4 disease.

CONCLUSIONS

Herein, the specificity of excluding nodal involvement clinically is 99.5% in tumors ≤ 4 cm and 100% in tumors ≤ 2 cm. Therefore, there may be a role for close observation in patients with cT1N0 lesions to mitigate morbidity from major pancreatic resection.

Perioperative safety and prognosis following parenchyma-preserving surgery for solid pseudopapillary neoplasm of the pancreas

BACKGROUND/OBJECTIVES

To evaluate perioperative safety and outcome of parenchyma-preserving pancreatectomy and risk factors of metastasis and recurrence for patients with solid pseudopapillary neoplasm (SPN).

METHODS

Demographic data, operative and pathological parameter, follow-up data of patients with SPN undergoing their first operation were collected in our single center from May 2016 to October 2021 and compared between regular pancreatectomy group and parenchyma-preserving surgery group. Risk factors for metastasis and recurrence were investigated.

RESULTS

A total of 194 patients were included, 154 of whom were female and the average age of all patients was 33 years old. Most patients were asymptomatic, with the most common complaint being abdominal pain or discomfort. Of them, 62 patients underwent parenchyma-preserving pancreatectomy including middle segment pancreatectomy and enucleation, and 132 patients underwent regular pancreatectomy including pancreaticoduodenectomy, distal pancreatectomy and total pancreatectomy. Patients in the parenchyma-preserving surgery group had a shorter duration of operation, less intraoperative bleeding, and decreased risk of combined organ removal and blood transfusion, with no statistical significance yet. The two groups exhibited a similar incidence of postoperative complications including grade B and C pancreatic fistula, delayed gastric emptying, postoperative pancreatic hemorrhage, and other complications, as well as radiological intervention, relaparotomy and the length of postoperative hospital stay. There were no perioperative deaths. All the patients, except 18 of those who discontinued follow-up, were alive with a median follow-up time of 31 months. Three patients in the regular pancreatectomy group were observed to have liver metastasis, and no metastasis was observed in the parenchyma-preserving surgery group. Significant risk factors for tumor metastasis and recurrence were tumor size, angioinvasion, and nerve infiltration.

CONCLUSIONS

Parenchyma-preserving surgery did not significantly increase the frequency of perioperative complications or recurrence and might be preferable if comprehensive conditions allow.

Resection of a recurrent solid pseudopapillary neoplasm of the pancreas after duodenal sparing pancreaticoduodenectomy: A case report

Introduction

Solid Pseudopapillary Neoplasm (SPN) is a rare pancreatic neoplasm with low malignant potential and a relative indolent course. Complete resection of the SPN is curative for most cases and has a high survival rate. Recurrences, though rare, can still occur despite adequate resection. Pancreaticoduodenectomy is commonly performed to treat pancreatic head SPNs. In recent years, duodenum-preserving pancreatic head resection (DPPHR) has been reported as a less radical and acceptable alternative.

Case presentation

We are reporting a case of 26-year old female who presented with a 7 month history of epigastric pain and increasing abdominal girth. She was diagnosed by MRI to have a huge but resectable pancreatic head mass and subsequently underwent duodenum-preserving pancreatic head resection (DPPHR) with pancreaticojejunostomy. Histopathologic examination revealed a solid pseudopapillary tumor (SPN) with lymphovascular invasion and negative margins of resection. The patient underwent hepaticojejunostomy 5 months after resection for biliary stricture. Surveillance imaging revealed tumor recurrence warranting re-exploration for recurrence 3 years after the initial surgery. Intraoperative findings revealed the mass at the distal pancreatic remnant, requiring distal pancreatectomy and splenectomy.

Discussion

Solid pseudopapillary neoplasms are rare pancreatic neoplasms. Surgical resection of SPNs affords long term cure with good 5-year survival rates for localized tumors Despite the low malignant potential of SPNs, relapse after resection can still occur.

Conclusion

Complete local resection of the tumor is the treatment of choice in SPNs. DPPHR should be considered as an alternative in young patients with a localized SPN in the pancreatic head.

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Solid pseudopapillary neoplasm (SPN) is a rare pancreatic neoplasm.

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Complete local resection of the tumor is the treatment of choice.

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Duodenum preserving pancreatic head resection should be considered as an alternative to pancreatoduodenectomy for SPN.

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Despite the low malignant potential, recurrences occur and complete resection of tumor recurrence is the ideal management.

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Large tumor size and lymphovascular invasion are notable risk factors for SPN recurrence.

Solid pseudopapillary neoplasm of the head of the pancreas: A case report

Introduction

and importance: Solid pseudopapillary tumor of the pancreas (SPN) or Frantz's tumor is a rare tumor of low malignant potential common in young women. The aim of this paper is to present and discuss a case of a solid pseudopapillary tumor of the pancreas occurring in a 19-year-old female.

Case presentation

A 19-year-old girl presented to our department with epigastric pain for two months, she had no clinical findings on physical examination. Abdominal Computed tomography scan (CT scan) showed the presence of a well-defined tumor arising from the pancreatic head measuring 9,1 × 8.1 × 8.5 cm, heterogeneous and with solid and necrosis components. The patient was subjected to surgery and histopathological examination confirmed the diagnosis of a pseudopapillary tumor of the pancreas.

Clinical discussion

This is an interesting case report of a rare tumor, in so far as without any adjuvant chemotherapy Prognosis of the tumor is better than other pancreatic tumors. surgical resection seems to be the best strategy in the management of SPT.

Conclusion

Close follow up is necessary for early detection of the recurrence and metastasis.

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Solid pseudopapillary tumor of the pancreas is a rare tumor of low malignant potential.

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The prognosis is favorable even in the presence of distant metastasis.

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Surgical resection is the treatment of choice.

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Close follow up is necessary to early detection of the recurrence and metastasis.

Non-gaussian models of 3-Tesla diffusion-weighted MRI for the differentiation of pancreatic ductal adenocarcinomas from neuroendocrine tumors and solid pseudopapillary neoplasms

PURPOSE

To assess the MRI performance in differentiating pancreatic ductal adenocarcinomas (PDACs), from solid pseudopapillary neoplasms (SPNs) and pancreatic neuroendocrine tumors (PNETs) using non-gaussian diffusion-weighted imaging models.

METHODS

This was a retrospective study of patients diagnosed with PDACs (01/2015-06/2019) or with PNETs or SPNs diagnosed (01/2011-12/2019) at our hospital. The lesions were randomized 1:1 to the primary and validation cohorts. The regions of interest (ROIs) were manually drawn on each slice at DWI (b = 1500 s/mm²) from 3 T MRI. D (diffusion coefficient), D* (pseudodiffusion coefficient), f (perfusion fraction), distributed diffusion coefficient (DDC), α (diffusion heterogeneity index), mean diffusivity (MD) and mean kurtosis (MK) were obtained. The parameters with largest performance for differentiation were used to establish a diagnostic model.

RESULTS

There were 148, 56, and 60 patients with PDAC, PNET, and SPN, respectively. For differentiating PDACs from SPNs, f and MK values were used to establish a diagnostic model with areas under the receiver operating characteristic curves (AUCs) of 0.92 and 0.89 in the primary and validation groups, respectively. For distinguishing PDACs from PNETs, α and MK values were used to establish a diagnostic model with AUCs of 0.87 and 0.86 in the primary and validation groups, respectively. The accuracy rate of the subjective evaluation with the assistance of non-gaussian DWI models for differentiating PDAC from SPNs and PNETs were higher than that of subjective diagnosis alone (P < 0.05).

CONCLUSIONS

The non-gaussian DWI models could assist radiologists in accurately differentiating PDACs from PNETs and SPNs.

Solid Pseudopapillary Neoplasms of the Pancreas: a Single-Center Experience and Review of the Literature

PURPOSE

Pancreatic solid pseudopapillary neoplasms (SPNs) are rare borderline tumours mainly affecting young female patients. The number of patients diagnosed with SPNs has increased significantly in the last decades owing to the increased use of cross-sectional imaging investigating different abdominal symptoms, whilst a significant proportion are incidentally discovered during the process of evaluating other pathologies. We herein present our institutional experience of patients with SPN who underwent curative resection focusing on clinical, pathological features, and the long-term outcomes.

METHODS

All patients undergoing pancreatectomy in our institution for SPN from January 2010 until December 2018 were included. Clinical, perioperative, histological, and long-term outcomes were collected and analysed.

RESULTS

During the inclusion period, a total of 19 patients had a pathological diagnosis of SPNs after surgical resection. Sixteen of them were female (84%), while the median patient age was 30 (range 16-66) years. Nine patients (47%) underwent distal pancreatectomy and splenectomy, 2 (11%) underwent spleen preserving distal pancreatectomy, 6 (32%) underwent pancreatoduodenectomy, one (5%) underwent total pancreatectomy, and one (5%) central pancreatectomy. Seventeen patients underwent R0 resection. During a median follow-up of 23 months, no tumour recurrence or death was recorded.

CONCLUSION

In our experience, SPNs are rare tumours with low malignant potentials. Surgical resection remains the gold standard treatment and is associated with good prognosis.

Solid pseudopapillary epithelial neoplasm (SPEN) of the pancreas involving the distal body and proximal tail: A case report

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Presentation, diagnosis and management of SPEN of the pancreas, a rare pancreatic tumor.

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SPEN is more common in women and can be more locally invasive and aggressive in men.

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Treatment involves surgical resection of the tumor and follow-up for recurrence.

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It has an excellent prognosis following resection; hence early identification and treatment are essential.

Introduction and importance

Solid Pseudopapillary Epithelial Neoplasm (SPEN) of the pancreas is a rare cystic exocrine tumor of the pancreas most commonly occurring in women between 30 and 40 years of age. This case report aims to demonstrate the clinicopathological findings encountered and the management of a patient diagnosed with SPEN.

Case presentation

An 18-year-old woman with gradually progressive and intermittent abdominal pain in the epigastric region presented to our outpatient department. Physical examination elicited tenderness to palpation in the epigastric area, and imaging findings suggested SPEN of the pancreas involving distal body and proximal tail region of the pancreas. The tumor was resected, and the diagnosis was confirmed on histopathology examination.

Clinical discussion

SPEN is a slow-growing tumor with a low-grade malignant potential, found incidentally in asymptomatic patients and symptomatic patients present with abdominal pain. The average tumor size is about 4 to 6 cm in diameter. Imaging is essential for diagnosis, and distal pancreatectomy with splenectomy was the most commonly reported procedure.

Conclusion

It is crucial to consider a diagnosis of SPEN in women with abdominal pain in the epigastric region as early surgical resection of the tumor results in resolution and excellent prognosis.

Solid-pseudopapillary neoplasm of the pancreas in a patient with familial adenomatous polyposis: a case report

Background

Familial adenomatous polyposis (FAP) is characterized by the presence of hundreds to thousands of colonic polyps, and extracolonic manifestations are likely to occur. Pancreatic tumors are rare extracolonic manifestations in patients with FAP, among which solid-pseudopapillary neoplasm (SPN) are extremely rare. We report here a patient with an SPN of the pancreas found during the follow-up of FAP.

Case presentation

A 20-year-old woman was diagnosed with FAP 3 years previously by colonoscopy which revealed less than 100 colonic polyps within the entire colon. She complained of left upper abdominal pain and a 10-cm solid and cystic pancreatic tumor was found by computed tomography scan. Solid and cystic components within the tumor were seen on abdominal magnetic resonance imaging. Simultaneous laparoscopic resection of the distal pancreas and subtotal colectomy was performed. Histopathological findings confirmed the pancreatic tumor as an SPN without malignancy. Abnormal staining of beta-catenin was observed by immunohistochemical study. Multiple polyps in the colorectum were not malignant. Molecular biological analysis from peripheral blood samples revealed a decrease in the copy number of the promoter 1A and 1B region of the APC gene, which resulted in decreased expression of the APC gene.

Conclusions

A rare association of SPN with FAP is reported. The genetic background with relation to beta-catenin abnormalities is interesting to consider tumor development. So far, there are few reports of SPN in a patient with FAP. Both lesions were treated simultaneously by laparoscopic resection.

Differentiating benign from malignant pancreatic cysts on computed tomography

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CT can distinguish between benign and premalignant or malignant pancreatic cysts.

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Solid component and septation were the only CT features that could differentiate benign from malignant cysts.

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Cyst wall enhancements on CT were more commonly observed in premalignant or malignant cysts than in benign cysts.

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CT is a necessary diagnostic modality to preoperatively detect and characterize pancreatic lesions.

Purpose

It is important to identify features on computed tomography (CT) that can distinguish between benign and premalignant or malignant pancreatic cysts to avoid unnecessary surgeries. This study investigated the preoperative diagnostic evaluation of cystic pancreatic lesions to determine how advanced imaging and clinical factors should guide management.

Methods

In total, 53 patients with 27 benign and 26 premalignant or malignant cysts were enrolled. CT features of the cysts were compared using univariate and multivariate analyses.

Results

On univariate analysis, a solid component (p < 0.01), septation (p < 0.01), location (p < 0.01), border (p < 0.01), wall enhancement (p = 0.01), lesion margins (p < 0.01), pancreatic atrophy (p = 0.04), and a cystic wall (p < 0.01) were all significantly different between benign and premalignant or malignant cysts. On multivariate analysis, only a solid component (p < 0.01) and septation (p < 0.01) were significant.

Conclusion

A thin cystic wall, uniform homogeneity, a clear border, the presence of septation, pancreatic atrophy, and the absence of both wall enhancements and solid components were more frequently seen in benign cysts. A thick wall, lack of homogeneity, the presence of wall enhancements and solid components, absence of septation, only a small degree of pancreatic atrophy, and unclear borders were more frequent among premalignant or malignant cysts. The only CT features to differentiate benign from premalignant or malignant cysts were a solid component and septation.

Radiomics Analysis Based on Diffusion Kurtosis Imaging and T2 Weighted Imaging for Differentiation of Pancreatic Neuroendocrine Tumors From Solid Pseudopapillary Tumors

Objective

To develop and validate a radiomics model of diffusion kurtosis imaging (DKI) and T2 weighted imaging for discriminating pancreatic neuroendocrine tumors (PNETs) from solid pseudopapillary tumors (SPTs).

Materials and Methods

Sixty-six patients with histopathological confirmed PNETs (n = 31) and SPTs (n = 35) were enrolled in this study. ROIs of tumors were manually drawn on each slice at T2WI and DWI (b = 1,500 s/mm²) from 3T MRI. Intraclass correlation coefficients were used to evaluate the interobserver agreement. Mean diffusivity (MD) and mean kurtosis (MK) were derived from DKI. The least absolute shrinkage and selection operator regression were used for feature selection.

Results

MD and MK had a moderate diagnostic performancewith the area under curve (AUC) of 0.71 and 0.65, respectively. A radiomics model, which incorporated sex and age of patients and radiomics signature of the tumor, showed excellent discrimination performance with AUC of 0.97 and 0.86 in the primary and validation cohort. Moreover, the new model had better diagnostic performance than that of MD (P = 0.023) and MK (P = 0.004), and showed excellent differentiation with a sensitivity of 95.00% and specificity of 91.67% in primary cohort, and the sensitivity of 90.91% and specificity of 81.82% in the validation cohort. The accuracy of radiomics analysis, radiologist 1, and radiologist 2 for diagnosing SPTs and PNETs were 92.42, 77.27, and 78.79%, respectively. The accuracy of radiomics analysis was significantly higher than that of subjective diagnosis (P < 0.05).

Conclusions

Radiomics model could improve the diagnostic accuracy of SPTs and PNETs and contribute to determining an appropriate treatment strategy for pancreatic tumors.

One size does not fit all for pancreatic cancers: A review on rare histologies and therapeutic approaches

Exocrine pancreatic neoplasms represent up to 95% of pancreatic cancers (PCs) and are widely recognized among the most lethal solid cancers, with a very poor 5-year survival rate of 5%-10%. The remaining < 5% of PCs are neuroendocrine tumors that are usually characterized by a better prognosis, with a median overall survival of 3.6 years. The most common type of PC is pancreatic ductal adenocarcinoma (PDAC), which accounts for roughly 85% of all exocrine PCs. However up to 10% of exocrine PCs have rare histotypes, which are still poorly understood. These subtypes can be distinguished from PDAC in terms of pathology, imaging, clinical presentation and prognosis. Additionally, due to their rarity, any knowledge regarding these specific histotypes is mostly based on case reports and a small series of retrospective analyses. Therefore, treatment strategies are generally deduced from those used for PDAC, even if these patients are often excluded or not clearly represented in clinical trials for PDAC. For these reasons, it is essential to collect as much information as possible on the management of PC, as assimilating it with PDAC may lead to the potential mistreatment of these patients. Here, we report the most significant literature regarding the epidemiology, typical presentation, possible treatment strategies, and prognosis of the most relevant histotypes among rare PCs.

MRI Texture Analysis for Differentiating Nonfunctional Pancreatic Neuroendocrine Neoplasms From Solid Pseudopapillary Neoplasms of the Pancreas

RATIONALE AND OBJECTIVES

To evaluate the value of texture analysis on preoperative magnetic resonance imaging (MRI) for identifying nonfunctional pancreatic neuroendocrine neoplasms (NF-PNENs) and solid pseudopapillary neoplasms (SPNs).

MATERIALS AND METHODS

This retrospective study included 119 patients who underwent MRI, including T2-weighted imaging with fat-suppression, diffusion-weighted imaging (DWI), apparent diffusion coefficient, precontrast T1-weighted imaging with fat-suppression (T₁WI+fs), and dynamic contrast-enhanced (DCE)-T₁WI+fs. Raw data analysis, principal component analysis, linear discriminant analysis, and nonlinear discriminant analysis (NDA) were used to classify NF-PNENs and SPNs. The results are reported as misclassification rates. The images were simultaneously evaluated by an experienced senior radiologist without knowledge of the pathological results. The misclassification rate of the radiologist was compared to the MaZda (texture analysis software) results. Neural network classifier testing was used for validation. In addition, 30 textures for each MRI sequence were investigated.

RESULTS

The misclassification rate of NDA was lower than that of other analyses. In NDA, DWI obtained the lowest value of 7.92%, but there was no significant difference among the sequences. The misclassification rate of the radiologist (34.65%) was significantly higher than that of NDA for all sequences. The validation results were good in the arterial phase and delayed phase. In the training set, entropy and sum entropy were optimal texture features on DWI and precontrast T₁WI+fs, while the mean and percentile seemed to be the more discriminative features on DCE-T₁WI+fs.

CONCLUSION

Texture analysis can sensitively distinguish between NF-PNENs and SPNs on MRI, and percentile and mean of DCE-T₁WI+fs images were informative for differentiation of neoplasms.

Similarities and differences in guidelines for the management of pancreatic cysts

Accurate diagnosis of Pancreatic cysts (PC) is key in the management. The knowledge of indications for surgery, the role of endoscopic ultrasound-guided fine needle aspiration, cyst fluid analysis, imaging, and surveillance of PC are all important in the diagnosis and management of PC. Currently, there are many guidelines for the management of PC. The optimal use of these guidelines with a patient-centered approach helps diagnose early cancer and prevent the spread of cancer.

Clinical update on the management of pseudopapillary tumor of pancreas

Solid pseudopapillary neoplasm (SPN) is a rare tumor with malignant potential which is generally located in the tail of pancreas. The prevalence of SPN has increased with widespread use of cross sectional imaging. SPN is often misdiagnosed due to nonspecific clinical presentation and accurate diagnosis is essential for optimal management. Endoscopic ultrasound-FNA with immunohistochemistry can help in preoperative diagnosis. Surgery is the treatment of choice and a successful R0 resection is curative. Overall, SPN has a good prognosis. This review article focuses on pathogenesis, diagnosis and management of SPN.

Management of a Pregnancy with a Solid Pseudopapillary Neoplasm of the Pancreas

A 26-year-old primigravid patient, at 35 weeks and 2 days of gestation, was referred to Hacettepe University Hospital for pancreatic mass, giant cervical myoma, maternal systemic lupus erythematosus, thrombocytopenia, and onset of preterm labor. At 36 weeks and 1 day of gestation (6 days after admission to the hospital), regular uterine contractions started and cervical dilatation with effacement was observed. Because of breech presentation and giant cervical myoma, a cesarean section was performed on the primigravid patient under general anesthesia. Four months after the birth, subtotal pancreatectomy, partial gastrectomy, duodenectomy, cholecystectomy, and omentectomy (Whipple procedure) were performed. The pathologic diagnosis was of a solid pseudopapillary neoplasm of the pancreas; the patient was discharged from hospital after ten days.

A, Lima S, Cardoso E, Brito E, Macedo-Lima M, Lyra Jr. D, Lyra P, Lima MM. Solid pseudopapillary tumor of the pancreas: Clinical features, diagnosis and treatment

Summary Introduction: Solid pseudopapillary tumor of the pancreas (SPTP) is a rare neoplasm of low malignant potential with uncertain behavior, diagnosed mainly in young women. Method: Our report comprises a series of cases of SPTP reviewed retrospectively, highlighting clinical, tomographic and immunohistochemical features, treatment performed and outcomes. Results: Thirteen patients were found to have pancreatic [solid] masses on computed tomography scan measuring a mean diameter of 8.8 cm. All patients underwent complete surgical excision. Immunohistochemistry confirmed diagnosis in all cases. Conclusion: SPTP occurs more frequently in young women. Diagnostic suspicion lies on the finding of a bulky, solid and cystic pancreatic mass. Imaging findings might provide diagnostic information before resection. Conservative approaches can be used in selected cases and survival rates are usually excellent following complete resection.

10-Year-Old Female with Acute Abdominal Pain with Pancreatic Mass

A previously healthy 10-year-old female presented to a local emergency department following three days of nausea and vomiting diagnosed with a solid pseudopapillary tumor. Solid pseudopapillary neoplasms are a rare form of pancreatic cystic neoplasm that typically presents in young females in their 20–30s and are very rare in children. These neoplasms often present as an asymptomatic tumor found on incidental imaging. When symptomatic they most commonly present with abdominal pain and can also cause a palpable abdominal mass, weight loss, gastrointestinal obstruction, and nausea and vomiting. Timely diagnosis of this rare neoplasm is very important because complete resection of the tumor is the definitive treatment and leads to an excellent long-term survival.

Pancreatic neuroendocrine tumor and solid-pseudopapillary neoplasm: Key immunohistochemical profiles for differential diagnosis

AIM

To reveal better diagnostic markers for differentiating neuroendocrine tumor (NET) from solid-pseudopapillary neoplasm (SPN), focusing primarily on immunohistochemical analysis.

METHODS

We reviewed 30 pancreatic surgical specimens of NET (24 cases) and SPN (6 cases). We carried out comprehensive immunohistochemical profiling using 9 markers: Synaptophysin, chromogranin A, pan-cytokeratin, E-cadherin, progesterone receptor, vimentin, α-1-antitrypsin, CD10, and β-catenin.

RESULTS

E-cadherin staining in NETs, and nuclear labeling of β-catenin in SPNs were the most sensitive and specific markers. Dot-like staining of chromogranin A might indicate the possibility of SPNs rather than NETs. The other six markers were not useful because their expression overlapped widely between NETs and SPNs. Moreover, two cases that had been initially diagnosed as NETs on the basis of their morphological features, demonstrated SPN-like immunohistochemical profiles. Careful diagnosis is crucial as we actually found two confusing cases showing disagreement between the tumor morphology and immunohistochemical profiles.

CONCLUSION

E-cadherin, chromogranin A, and β-catenin were the most useful markers which should be employed for differentiating between NET and SPN.

Recurrence of Solid Pseudopapillary Tumor: A Rare Pancreatic Tumor

Solid pseudopapillary tumor of the pancreas (SPTP) is a rare disease of young females that does not usually recur after resection. Here we report a case of an elderly female with history of SPTP ten years ago who presented with anorexia and a palpable left lower quadrant abdominal mass. Imaging revealed metastatic disease and US-guided biopsy of the liver confirmed the diagnosis of SPTP. Due to her advanced age and comorbidities, she elected to undergo hospice care. The objective of this case report is to increase awareness of this tumor and its possibility of recurrence, necessitating further guidelines for follow-up.

Less Aggressive Surgical Procedure for Treatment of Solid Pseudopapillary Tumor: Limited Experience from a Single Institute

Objectives

To evaluate the clinical characteristics and radiological features of solid pseudopapillary tumor (SPT) and assess surgical therapy strategy.

Methods

A retrospective review was performed in 62 patients pathologically confirmed of SPT treated between 2003 and 2014. The clinical features, radiological examinations and surgical strategies were analyzed.

Results

56 females and 6 males were included in this study, mean age was 26 years old (range: 8–66 years old) with mean size of the tumor was 7.2 cm (range: 3–15 cm), and most tumor were commonly located in the head of pancreas (n = 29). Among all the cases, 3 patients had liver metastasis and underwent resection of SPT and liver metastasis. Furthermore, we performed 29 cases of local tumor excision; other patients underwent pancreaticoduodenectomy, middle pancreatectomy, middle pancreatectomy with splenectomy, distal pancreatectomy with spleen preservation, distal pancreatectomy with splenectomy and duodenum-preserving pancreatic head resection. No patient suffered from lymph node metastases. After median follow-up of 46 months (range: 2–135 months), no mortality or local recurrence or distant metastasis was found.

Conclusions

Solid pseudopapillary tumor is a latent malignant tumor with excellent prognosis. If feasible, less aggressive resection without regular lymphadenectomy is recommended for treatment of patients with SPT.

Imaging of pancreatic neoplasms

Ductal adenocarcinoma accounts for 85% to 90% of all solid pancreatic neoplasms, is increasing in incidence, and is the fourth leading cause of cancer-related deaths. There are currently no screening tests available for the detection of ductal adenocarcinoma. The only chance for cure in pancreatic adenocarcinoma is surgery. Imaging has a crucial role in the identification of the primary tumor, vascular variants, identification of metastases, disease response assessment to treatment, and prediction of respectability. Pancreatic neuroendocrine neoplasms can have a distinctive appearance and pattern of spread, which should be recognized on imaging for appropriate management of these patients.

Solid pseudopapillary tumor of the pancreatic: evaluation of clinical, radiological and surgical profiles

OBJECTIVE

To describe the clinical, radiological and surgical features of solid pseudopapillary tumor of the pancreas.

METHODS

We conducted a retrospective, observational study evaluating the multi-institutional clinical, radiological and surgical patients with a diagnosis of solid pseudopapillary tumor of the pancreas undergoing surgical treatment.

RESULTS

We identified eight patients in three hospitals in the state of Amazonas, seven females, six under the age of 30. The neoplasia predominated in the head of the pancreas. Five patients underwent pancreaticoduodenectomy, one enucleation, one distal pancreatectomy, and one was considered unresectable.

CONCLUSION

Solid pseudopapillary tumor of the pancreas predominated in young female patients, predominantly located in the pancreatic head.

Solid pseudopapillary neoplasm of the pancreas associated with familial adenomatous polyposis

A man in his thirties visited our hospital for an evaluation of a 12×10-mm pancreatic solid tumor that was accidentally detected on computed tomography performed for follow-up of familial adenomatous polyposis (FAP). We diagnosed the patient with a solid pseudopapillary neoplasm (SPN) based on endoscopic ultrasound-guided fine-needle aspiration, and he underwent pancreaticoduodenectomy. Small SPN tumors appear as solid tumors, without typical features of SPN, making the definitive diagnosis more difficult. The genetic background of FAP patients can predispose them to SPN, and imaging of the pancreas should be performed at prescribed intervals in FAP patients.

Clinical Features and Management of Pancreatic Solid Pseudopapillary Tumor

Solid pseudopapillary tumor (SPT) is a rare pancreatic tumor with low malignant potential. Between February 2006 and May 2013, six patients were affected by SPT. Two patients were male and four were female. Median age of the patients was 31.5 years (range, 13 to 47 years). One patient was preoperatively diagnosed by an endoscopic ultrasound-guided fine-needle aspiration biopsy. Pancreaticoduodenectomy was performed in two and distal pancreatectomy was done in four. One operation of those was laparoscopic distal pancreatectomy. In this series, recurrence or distant metastasis was not reported and successful outcome was achieved in all patients. In conclusion, whereas diagnosis of SPT is difficult, it can be diagnosed by endoscopic ultrasound-guided fine-needle aspiration biopsy preoperatively. It should be treated by surgery, and laparoscopic operation can be considered.

Unresectable isolated hepatic metastases from solid pseudopapillary neoplasm of the pancreas: a case report of chemosaturation with high-dose melphalan

BACKGROUND/OBJECTIVES

Solid pseudopapillary neoplasms of the pancreas (SPN) are rare tumors. For patients with unresectable liver metastases of SPN, no standard treatment has been defined so far. Here we report a case of a 40-year-old woman with SPN and metastases confirmed to the liver, and disease progression in the liver after primary tumor resection and chemotherapy with gemcitabine and cisplatin.

METHODS

Chemosaturation with percutaneous hepatic perfusions is a minimally invasive, repeatable regional therapy which delivers chemotherapy directly to the liver while limiting systemic toxicity. As an individual treatment approach, the patient was treated with chemosaturation with percutaneous hepatic perfusions of melphalan.

RESULTS

The procedure was performed twice within 8 weeks after which the liver metastases showed a marked reduction in size and vascularization (partial response). Grade 3 leukopenia after the second procedure was managed effectively with granulocyte colony-stimulating factor. No other toxicities were observed. Ten months after initiating treatment, the patient had a good performance status and remained stable.

CONCLUSIONS

For SPN with unresectable liver metastases and progression despite systemic treatment, repeat chemosaturation with high-dose melphalan may also offer an effective regional treatment option.

Clinical and pathological features of solid pseudopapillary neoplasms of the pancreas at a single institution

AIMS

The aim of this study was to determine the clinicopathological features and surgical management of solid pseudopapillary neoplasms (SPNs) of the pancreas at a single institution.

METHODS

We investigated 34 patients (5 males and 29 females) who underwent surgery for pathologically confirmed SPNs between 1994 and 2012.

RESULTS

Clinical symptoms were absent in 58.8% of the patients. The median tumor diameter was 42.7 mm. All tumors were successfully removed by R0 resection. Pathologically, 5.9% had duodenum invasion and 2.9% had pancreatic serosal invasion, but there was no lymph node metastasis. Radiological findings showed calcification in 39.4% of the patients, capsule formation in 51.5%, cystic components in 69.7%, solid components in 93.9% and internal bleeding in 36.4%. Immunohistochemically, neuron-specific enolase was positive in 100% of the patients, nuclear accumulation of β-catenin in 100% and CD10 in 78.8%. There were no recurrences reported at the median follow-up (67 months). Regarding gender differences, the cystic component in radiological imaging was the only significant finding among the features studied (p = 0.01).

CONCLUSIONS

R0 resection with appropriate procedures appears to be sufficient for patients with SPNs, even for locally invasive tumors. There were no significant differences between genders except for the cystic component on radiological imaging.

Surgical therapy of a large pancreatic solid-pseudopapillary neoplasm during pregnancy

Solid-pseudopapillary neoplasms (SPNs) of the exocrine pancreas are rare, accounting for only 2% of pancreatic tumours. These tumours predominantly affect women during the second and third decades of life. They frequently present with vague symptoms and can pose a diagnostic challenge. Surgical resection remains the treatment of choice that can cure up to 95% of patients when negative resection margins are obtained. SPNs diagnosed during pregnancy are exceptional and with profound implications on the mother and fetus. The authors present a case of an asymptomatic SPN in a 24-year-old woman diagnosed at 14 weeks of gestation on a routine prenatal ultrasound. Distal pancreatectomy, splenectomy and cholecystectomy were successfully performed at 18 weeks of gestation. A healthy full-term male child was born 5 months following surgery without complications.

Pleomorphic solid pseudopapillary neoplasm of the pancreas: degenerative change rather than high-grade malignant potential

Solid pseudopapillary neoplasms (SPNs) are rare tumors of the pancreas characterized by poorly cohesive uniform cells with solid and pseudopapillary growth patterns. Nuclear pleomorphism is not a well-recognized feature of SPNs and may complicate differentiation from other pancreatic neoplasms. We compared histologic, immunohistochemical, and clinical features of 18 pleomorphic SPNs with 121 conventional SPNs. The prevalence of pleomorphic SPN was 12.9% (18/139). Pleomorphic SPNs arose in older patients (median, 45 years versus 32 years; P < .001), but no differences were found in sex, tumor location, recurrence, and metastasis when compared with conventional SPNs. Except for pleomorphic nuclei, other cytologic and histologic features of pleomorphic SPNs, such as growth pattern, tumor size, infiltrative pattern, tumor extension, mitosis, and Ki-67 labeling index, were not different from those of conventional SPNs. Pleomorphic SPNs showed a significantly higher p53 protein expression (64.7% [11/17 cases]) than that of conventional SPNs (1.8% [2/112 cases], P < .001). However, immunoreactivity for β-catenin and E-cadherin was not different between pleomorphic and conventional SPNs. A TP53 gene mutation was observed in 2 of 3 p53-immunoreactive pleomorphic SPNs. In summary, nuclear pleomorphism occurs in a subset of SPNs. They are more often p53 immunoreactive than SPNs without pleomorphism, and some harbor TP53 gene mutations. However, pleomorphic SPNs do not appear to be more aggressive than conventional SPNs. Low mitotic rate and Ki-67 labeling index may suggest nuclear pleomorphisms as degenerative changes. Recognition of typical poorly cohesive tumor cells and immunohistochemical features could establish the correct diagnosis of SPNs.

Clinical presentation and comparison of surgical outcome for segmental resection vs. Whipple's procedure for solid pseudopapillary tumor: Report of six new cases & literature review of 321 cases

AIM

Report 6 new cases of solid-pseudopapillary-pancreatic-tumor, comprehensively review 321 cases reported in American literature, and compare outcomes for segmental resection vs.. Whipple's procedure.

METHODS

Cases of solid-pseudopapillary-tumor at William Beaumont Hospital, 1999-2011, identified by computerized analysis of pathology reports. Comprehensive review of all American cases identified by computerized literature review. Segmental resection includes open/laparoscopic central pancreatectomy and anatomic distal pancreatectomy, but excludes enucleation.

RESULTS

Six cases of solid-pseudopapillary-pancreatic-tumors (0.5% of all solid pancreatic lesions), occurred during 1999-2011 at the hospital. Mean age at diagnosis = 27.7 years. All 6 were female. All patients had abdominal pain. Mean symptom duration = 10.0 days. All patients had normal routine blood tests. Mean APACHE II score at diagnosis = 1.8. All six patients had single heterogeneous lesions, with cystic/solid components. All patients underwent surgery: segmental resection-4, Whipple's procedure-2. Tumors were uniformly diagnosed by surgically resected tissue. Mean tumor size = 5.7 cm. Mean postoperative length of stay = 4.0 days for segmental resection (N = 4) vs. 14.0 days for Whipple's procedure (N = 2). All 6 patients are alive and well to-date, without evident local recurrence or metastasis. In a literature review, 45 patients undergoing Whipple's procedure versus 34 patients undergoing segmental resection, had significantly longer mean postoperative hospitalization (16.4 vs. 4.3 days, p = 0.01), and had increased unadjusted mortality (20.2% vs. 2.2%, p = 0.018). However, this mortality difference became insignificant when adjusting for longer mean follow-up of Whipple's procedure patients (Kaplan-Meier-survival-curve, p = 0.75).

CONCLUSIONS

This work suggests segmental resection of these pancreatic tumors localized to the body/tail may have a better surgical outcome than Whipple's procedure for tumors localized to the pancreatic head. Further studies are necessary.

Comparison of F-18-FDG PET/CT findings between pancreatic solid pseudopapillary tumor and pancreatic ductal adenocarcinoma

OBJECTIVE

Pancreatic solid pseudopapillary tumor (SPT) is a rare benign tumor. Little data are available on positron emission tomographic/computed tomographic (PET/CT) characteristics of this tumor. Therefore, we analyzed the metabolic characteristics of SPT using F-18-FDG PET/CT and compared the results with those of pancreatic ductal adenocarcinoma.

METHODS

We retrospectively reviewed the records of 11 SPT patients and 46 patients with ductal adenocarcinoma. Ten SPT patients had primary tumors and 1 patient had metastatic SPT. Maximum standardized uptake value (max SUV), mean SUV, metabolic tumor volume (MTV), total lesion glycolysis (TLG), and tumor-to-background ratio (TBR) were evaluated. Mann-Whitney U test between pancreatic SPT and ductal adenocarcinoma was performed. In addition, age, gender and tumor size-adjusted analysis of covariance (ANCOVA) was done between pancreatic SPT and ductal adenocarcinoma.

RESULTS

Compared with pancreatic ductal adenocarcinomas, SPTs had significantly higher tumor size-adjusted MTV and TLG. MTV and TLG values were significantly correlated with T-stage of the SPTs. In 1 SPT patient, metastases in the liver and mesentery were revealed by intense uptake of FDG on F-18-FDG PET/CT, and after PET/CT had suggested the presence of pancreatic SPT.

CONCLUSION

We recommend that SPT be considered when a solid pancreatic mass with increased FDG metabolism is encountered on PET/CT. F-18-FDG PET/CT may be useful in detecting subtle metastases of SPT.

European experts consensus statement on cystic tumours of the pancreas

Cystic lesions of the pancreas are increasingly recognized. While some lesions show benign behaviour (serous cystic neoplasm), others have an unequivocal malignant potential (mucinous cystic neoplasm, branch- and main duct intraductal papillary mucinous neoplasm and solid pseudo-papillary neoplasm). European expert pancreatologists provide updated recommendations: diagnostic computerized tomography and/or magnetic resonance imaging are indicated in all patients with cystic lesion of the pancreas. Endoscopic ultrasound with cyst fluid analysis may be used but there is no evidence to suggest this as a routine diagnostic method. The role of pancreatoscopy remains to be established. Resection should be considered in all symptomatic lesions, in mucinous cystic neoplasm, main duct intraductal papillary mucinous neoplasm and solid pseudo-papillary neoplasm as well as in branch duct intraductal papillary mucinous neoplasm with mural nodules, dilated main pancreatic duct >6mm and possibly if rapidly increasing in size. An oncological partial resection should be performed in main duct intraductal papillary mucinous neoplasm and in lesions with a suspicion of malignancy, otherwise organ preserving procedures may be considered. Frozen section of the transection margin in intraductal papillary mucinous neoplasm is suggested. Follow up after resection is recommended for intraductal papillary mucinous neoplasm, solid pseudo-papillary neoplasm and invasive cancer.

Solid pseudopapillary neoplasm of the pancreas

Solid pseudopapillary neoplasms (SPNs) are rare entities accounting for between 0.13 and 2.7 per cent of pancreatic tumours. This neoplasm has a predilection for females under the age of 35. The authors report this case of a SPN incidentally discovered when a 59-year-old female underwent a chest x-ray to investigate a wheeze. A subsequent CT abdomen revealed a 10 cm well-circumscribed mass adjacent to the tail of the pancreas. This mass was successfully resected. Immunohistochemical markers established the diagnosis of a SPN. The wheeze associated with the presentation of this case was unrelated to the tumour which was an incidental finding. These neoplasms are largely asymptomatic and indolent reaching a large size before detection. Diagnosis is confirmed on histology and in this case surgical resection was curative and there was no metastasis at presentation.