Papillary epithelial neoplasm of pancreas in a child. Report of a case with electron microscopy

Solid Pseudopapillary Neoplasm - Case Series and Review of Literature

Solid-pseudopapillary neoplasm (SPN) is a variety of solid and cystic tumors of the pancreas. It was first described by Frantz in 1959. It is an unusual form of pancreatic carcinoma, with unknown etiopathogenesis, which accounts for about 0.17 to 2.7% of all pancreatic tumors. Here, we are describing 5 cases of pancreatic solid pseudopapillary neoplasm, out of 180 pancreatic tumors, operated in our institution in the 5-year period (2015-2020). Also, we have reviewed all available case series (from 2006 to 2020) in the literature, of pancreatic pseudopapillary neoplasm, for demographic information, etiopathogenesis, diagnosis, and extent of operation to establish the optimal management of this condition. Retrospective analysis of pancreatic tumors was carried out from February 2015 to January 2020. A total of 180 patients underwent pancreatic resection in this period for pancreatic tumor, out of which, the solid pseudopapillary neoplasm was confirmed in 5 cases (2.76%). Among these 5 cases, 4 cases (80%) were female and one (20%) male, with age group range from 14 to 45 years (mean age - 28 years). Abdominal pain was the most frequent presenting symptom (60%). Mean tumor diameter was 6.9 cm (range, 2-18 cm). Two patients were diagnosed preoperatively by CECT and MRI findings, and three patients were diagnosed preoperatively by percutaneous/USG-guided and CT-guided FNA cytology. Two patients underwent pancreatoduodenectomy; one patient underwent enucleation; and two patients underwent spleen preserving distal pancreatectomy. Four patients are alive and on regular follow-up, while one patient died on the 5th post-operative day due to post-operative sepsis.

Pancreatic head sparing surgery for solid pseudopapillary tumor in patients with agenesis of the dorsal pancreas

BACKGROUND

This study aimed to clarify the feasibility and justification of pancreatic head sparing (PHS) enucleation for patients with agenesis of the dorsal pancreas (ADP) associated with a solid pseudopapillary tumor (SPT).

METHODS

Data of the SPT patients with and without ADP, including clinical presentations, surgical options, and surgical and survival outcomes, were recruited for comparison.

RESULTS

A total of 31 patients with SPTs were included, three of whom displayed ADP and underwent PHS enucleation. Surgical complications were comparable between the groups. Overall, the 5- and 10-year disease-free survival rates were 100% and 90%, respectively. The 20- and 25-year overall survival rates were 100% and 66.7%, respectively. Only one patient (3.2%) developed tumor recurrence 7.3 years after pancreatectomy for an SPT with lymph node involvement, and the patient survived 24.5 years after the initial operation. No tumor recurrence occurred in any patient with ADP after PHS enucleation.

CONCLUSION

PHS enucleation seems to be feasible and justifiable for SPT patients with ADP in terms of surgical and survival outcomes, and this approach could be recommended to avoid pancreatic insufficiency.

Clinical profile and outcome of solid pseudopapillary neoplasm of the pancreas: A retrospective study on 28 patients

BACKGROUND

Solid pseudopapillary neoplasms (SPN) of the pancreas are rare tumors accounting for 0.9-2.7% of all exocrine pancreatic tumors. Very few studies comprising of more than 10 patients have been published. The aim of the present study is to report on our experience with SPNs over a period of 14 years from a tertiary center of Eastern India.

METHODOLOGY

Data of all patients whose histopathology reports of surgically resected specimen confirmed SPN were retrospectively reviewed in the present study.

RESULTS

Twenty-eight patients had a pathologically confirmed diagnosis of SPN. Twenty-five (89.3%) patients were females with a median age of 26 (15-45) years. Abdominal pain (89.2%) was the most common presenting symptom. Abdominal mass was palpable in 12 (42.8%) patients. The mean size of the tumor was 9.03 cm (range, 4-25 cm). The most common location of the tumor was in the body and tail of pancreas (35.7%). The most commonly performed operation was distal pancreaticosplenectomy (n = 17, 60.7%), followed by Whipple's procedure (n = 8, 28.5%). Thirty postoperative complications developed in 23 (82.1%) patients. The operative mortality was 3.5% (n = 1). The median hospital stay was 10 (5-25) days. Over a median follow-up period of 36 months (range), no patient developed recurrence.

CONCLUSION

Although the size of tumor was quite large at the time of initial presentation, complete surgical resection was possible in all the patients. In experienced hand, surgery can be performed with acceptable perioperative mortality and excellent long-term outcomes.

Solid Pseudopapillary Neoplasm of the Pancreas Presenting With Gastric Outlet Obstruction

Solid pseudopapillary neoplasm (SPN) of the pancreas are rare tumors accounting for a minor portion of all exocrine pancreatic tumors. It usually occurs in young women. It has a very low malignant potential with a relatively indolent clinical course. A small subset of patients exhibits pathological features of malignancy. Herein, we present a rare case of pancreatic SPN that presented with gastric outlet obstruction. Despite the characteristic computed tomography (CT) findings, due to its rarity, it was missed in more common conditions such as gastrointestinal stromal tumors. In our case, we found that the tumor was causing extrinsic duodenal compression leading to gastric outlet obstruction, creating a diagnostic dilemma.

[Metastatic solid pseudopapillary tumor in the perinephric fat without a primary identified focus]

Solid pseudopapillary tumor of the pancreas is an extremely rare neoplasm of the exocrine portion of this organ, which affects mostly young women and is characterized by a low malignancy potential and a relatively benign clinical course. According to the literature, even in disease progression as metastases, the overall 5-year survival rate is more than 95%. The paper describes a clinical case of a female patient with a solid pseudopapillary pancreatic tumor regarded as a metastatic neoplasm in the retroperitoneal space after surgical treatment previously performed in 2001.

Rare Pseudopapillary Neoplasm of the Pancreas: A 10-Year Experience

Introduction

The solid pseudopapillary epithelial neoplasm (SPN) is a rare form of pancreatic neoplasm with an incidence of 2-3% of all pancreatic tumours. The recent increase in incidence is attributed to the increasing use of imaging techniques for nonspecific abdominal complaints. We report our institutional experience in the management of this tumour over the last decade.

Method

We retrospectively analyzed from a prospectively maintained database of patients from January 2011 to December 2020 who were operated upon for SPN. All the patients were followed till date.

Results

Of 479 patients operated on for various types of pancreatic tumours during this period, 15 (3.1%) had SPN. The mean age of presentation was 28 years with a female preponderance (12/15, 80%). The most common location was the body and tail of the pancreas (66%), and the mean size was 6.4 cm (2–15 cm). The tumour extent was defined as ‘borderline resectable' in 20% of cases. Distal pancreatectomy was done in 11 patients with spleen preservation in 3. R0, R1, and R2 resection were done in 12, 2, and 1 patient(s), respectively. The operative mortality was 6.7%. All the patients are doing well on follow-up.

Conclusion

SPN is a low-grade malignant tumour with a strong female predilection. Clinical manifestations have no specificity, imaging examination only contributes tumour location, and the final diagnosis rests on pathology. Surgery is the main modality of treatment and carries a good prognosis.

Central pancreatectomy for solid pseudopapillary neoplasm: A pancreatic-preserving procedure

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Pseudopapillary Neoplasm of the pancreas is a rare disorder with benign behavior.

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Preoperative diagnosis can change a treatment plan from a major to a simple operation.

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The treatment should aim for R0 resection; incomplete resection results in recurrence.

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Although recurrence is rare; it is considered a cause of poor outcomes.

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The overall 5-year survival is reported to be 97%.

Introduction and importance

Solid pseudopapillary neoplasm (SPN) is a rare pancreatic disorder that usually affects young women with no or nonspecific clinical manifestation. It accounts for approximately 1% of pancreatic neoplasms. The incidence of SPN is increasing, owing to improved imaging techniques and better recognition of this entity. Although most patients with SPNs have a favorable prognosis after radical resection, local recurrence or metastasis still occurs after surgery.

Case presentation

We present a 15-year-old female with a small solid pseudopapillary neoplasm in the Pancreas' proximal body. The patient presented with nonspecific symptoms and was diagnosed incidentally.

Clinical Discussion

The patient underwent a central pancreatectomy and was discharged on the fifth postoperative day without complications. Central pancreatectomy may prevent devastating complications of pancreaticoduodenectomy surgery.

Conclusion

As SPN is a rare entity of pancreatic tumors, the surgical options for management are still debated. The respect for surgery should account for the tumor site and size. Also, life expectancy and surgical complications for each choice should be considered. In localized disease, segmental resection may prevent devastating complications of radical resection.

A Rare Case of Large Solid Pseudopapillary Tumor in a Child

BACKGROUND Solid pseudopapillary tumor (SPT) is a rare disease with low-grade malignancy potential of the pancreas. SPT accounts from 0.13% to 2.7% of all exocrine pancreatic tumors. We report an unusual case with a large solid pseudopapillary tumor that was diagnosed and treated in our pediatric hospital. CASE REPORT A 15-year-old girl was incidentally found to have an abdominal mass on ultrasound examination. Computed tomography (CT) scans showed a well-defined tumor that was raised in part of the tail and body of the pancreas. The tumor size at greatest diameter was 18.2 cm. A mass excision was performed to remove the whole tumor, and the histopathological findings confirmed SPT without evidence of malignancy. CONCLUSIONS SPT is a rare disease that mostly affects young female patients. The clinical symptoms of this disease are unspecific. The prognosis of SPT is good, even in case of distant metastasis. Close follow-up is required to detect metastasis so the appropriate treatment method can be chosen.

Systematic Review and Meta-analysis of Minimally Invasive Pancreatectomies for Solid Pseudopapillary Neoplasms of the Pancreas

OBJECTIVES

We report the first systematic review and meta-analysis on minimally invasive pancreatectomy (MIP) for solid pseudopapillary neoplasms (SPPN) of the pancreas.

METHODS

A systematic review of all studies reporting patient characteristics and outcomes of MIP for SPPN was conducted.

RESULTS

We reviewed 27 studies comprising 149 patients with SPPN managed via MIP. Five were comparative retrospective cohort studies, comprising 46 and 60 patients in the minimally-invasive and open groups, respectively. Tumor size was smaller in the minimally-invasive group (mean difference, -2.20; 95% confidence interval (CI), -3.09 to -1.32; P < 0.001). The MI group had lower intraoperative blood loss (mean difference, -180.19; 95% CI, -344.28 to -16.09; P = 0.03) and transfusion requirement (relative risk, 0.24; 95% CI, 0.06-0.94; P = 0.04), and a shorter time to diet (mean difference, -2.99; 95% CI, -3.96 to -2.03; P < 0.001) and length of stay (mean difference, -3.61; 95% CI, -6.98 to -0.24; P = 0.04). There was no significant difference in operating time, margin positivity, postoperative morbidity, and postoperative pancreatic fistula rates.

CONCLUSIONS

Minimally invasive pancreatectomy for SPPN is associated with decreased intraoperative blood loss and transfusion requirements and a shorter postoperative time to diet and hospital stay.

Outcome of minimally-invasive versus open pancreatectomies for solid pseudopapillary neoplasms of the pancreas: A 2:1 matched case-control study

Backgrounds/Aims

Solid pseudopapillary neoplasm (SPPN) is typically seen in young healthy females who would likely benefit from minimally-invasive pancreatectomy (MIP). A few comparative studies have suggested that MIP is associated with favorable outcomes when compared to the open approach for SPPN. This study aims to mitigate potential selection bias by performing a matched case-control study comparing MIP vs open pancreatectomy (OP) for SPPN.

Methods

We performed a single-institution retrospective electronic chart review of all patients who underwent surgery for pathologically confirmed SPPN between 2000 and 2017. A 2:1 matched comparison using age, gender, tumor size and the type of pancreatectomy was performed between OP and MIP.

Results

A total of 40 patients with a median age of 40.3 years (range 16.5-64.4) and female sex predominance (n=34, 85.0%) underwent surgery during the study period. Nine patients underwent MIP. Matched comparison between 18 OP and 9 MIP demonstrated that MIP was associated with a longer median operating time (305 vs 180 min, p=0.046) and shorter median postoperative stay (6 vs 9 days, p=0.015). There were no significant differences in intraoperative blood loss, blood transfusion requirements, postoperative morbidity (including postoperative pancreatic fistula) and mortality, resection margins, lymph node yield and long-term survival.

Conclusions

MIP is a safe and viable option in the management of SPPN with the benefit of a shorter postoperative length of stay at the expense of a longer operation time. There was no significant difference in oncologic outcomes between both groups of patients.

Solid-pseudopapillary Neoplasms of the Pancreas is still an Enigma: a Clinicopathological Review

The solid-pseudopapillary neoplasm of the pancreas is a rare but enigmatic entity occurring mainly in young women. Since the first description by V. Frantz in 1959 the terminology of this tumor has continuously changed but it has remained simply descriptive, because the exact histogenesis is still obscure. Although in majority of cases the survival is excellent, nevertheless, the expected prognosis is not exactly predictable. In this review the authors aim to summarize its clinico-pathological features, the expected biological behavior, the molecular alterations, the immune phenotype and discuss the putative histogenesis. From diagnostic point of view, the salient histological characteristic findings are analyzed that would help to differentiate it from other, look-alike pancreatic tumors, and suggestions are made about the desirable content of the histological report.

[The histological and immunohistochemical diagnosis of solid pseudopapillary neoplasm of the pancreas and its differential diagnosis]

Solid pseudopapillary neoplasm of the pancreas is a rare tumor of uncertain histogenesis, described separately by Gruber and Frantz, that accounts for between approximately 1% and 3% of pancreatic neoplasms. It is characterized by a cystic and solid pattern of growth patterns with formation of pseudopapillae. It occurs primarily in young women, although cases in children and older patients and men have been reported. The tumor is of low-grade malignant potential, as the majority of the cases are cured by simple but complete surgical resection. Knowledge of the unique morphologic characteristics of this neoplasm is essential for the correct diagnosis. We review herein the pathologic and immunohistochemical features of this neoplasm and its differential diagnosis with other pancreatic tumors.

Solid pseudopapillary neoplasm of the pancreas: Clinical-pathological features and management, a single-center experience

Solid pseudopapillary neoplasm of the pancreas is a rare tumor of low malignancy that occurs most often in females. The study describes the clinicopathologic characteristics of the tumor and common differential diagnoses. Data were collected from a prospectively maintained database. Of 1661 patients operated for pancreatic tumors between January 2001 and September 2018, 15 patients were recorded. Patients included 12 females and 3 males, median age 40 (range 10 -87) years. Computed tomography or magnetic resonance imaging was diagnostic in eight patients and a preoperative biopsy in eight out of 10 patients. Median tumor size was 5 cm (range 2 -16 cm), 12 tumors were in the head, six in the body, and three in the tail of the gland. All patients except one had radical resection including one with hepatic and lymph node metastases, no patient underwent oncologic treatment. All patients are alive from 17.5 to 209.4 months postoperatively and without recurrence. Radical operation is usually curative and should also be offered to patients with metastases or recurrence as oncologic treatment has limited effect.

Survival and Prognostic Factors in Patients With Solid Pseudopapillary Neoplasms of the Pancreas

OBJECTIVES

Prognostic factors for solid pseudopapillary neoplasms (SPN) of the pancreas have been incompletely defined in the literature. We aimed to use the National Cancer Database to describe survival and characterize prognostic factors in patients with pancreatic pseudopapillary neoplasms.

METHODS

We identified 304 patients with pancreatic SPN diagnosed between 2004 and 2012 using the National Cancer Database. All patients were included in the survival analysis. Kaplan-Meier method, χ, and log-rank tests were used for statistical analysis. Cox proportional hazard regression model was used for multivariate analysis.

RESULTS

The median age at diagnosis was 36.5 years. Eighty-five percent of patients were female, 69% were white, and 25% were black. Metastases were observed in 5% of patients. Median tumor size was 5.1 cm. Ninety-two percent of patients underwent primary tumor resection. At 60 months, 98% of patients who underwent resection were alive, and 40% who did not undergo resection were alive. On multivariate analysis, female sex, resection of primary tumor, and absence of metastasis were correlated with improved survival.

CONCLUSIONS

Patients with SPN who undergo resection have an excellent survival at 5 years. Surgery should be considered in all patients with this diagnosis.

Solid Papillary Neoplasm of the Pancreas: A Case Report

Solid pseudopapillary neoplasm of the pancreas, solid and cystic, is a rare disease compared to ductal adenocarcinoma. The tumor most often affects women of African race aged in their twenties or thirties. We report the case of a 48-year-old man affected by solid pseudopapillary neoplasm of the pancreas treated by distal splenopancreasec-tomy. The patient was discharged on the 10th postoperative day in good general condition, feeling normal and with blood chemistry values within normal limits. The main characteristic differentiating papillary tumors of the pancreas from ductal adenocarcinoma is that in the latter case surgical eradication is a definitive solution and no other treatment is required, as confirmed by our case and those reported in the literature.

Solid pancreatic pseudopapillary tumor managed laparoscopically: A case report and review of the literature

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Solid pancreatic pseudopapillary tumors are a rare neoplasms with not well known pathogenesis.

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Imaging is not able to provide a precise diagnostic orientation. The essential role is played by surgery and histological examination.

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Immunohistochemistry shows a possible correlation between the Beta-catenin mutations or alteration of the E-cadherin and tumor development.

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Laparoscopic technique has proven to be the gold standard for the countless advantages found compared to the open technique.

Background

Solid pancreatic pseudopapillary tumors are a rare neoplasms, about 1–3% of all pancreatic neoplasms. This cancer mainly affects women between the third and fourth decade of life.

They are not well known; the molecular origins represent a low degree of malignancy, in which the complete resection is curative. We report our experience with a case report of SPT in a young man.

Presentation of case

Thirty-six years old male patient with a mass about 10 cm in the pancreatic tail and splenic ilum. After following CT and MR, the patient was subjected to surgery. Histophatological result was solid tumor pseudopapillary of pancreas with no pathological lymph nodes.

Discussion and conclusion

Solid pseudopapillary neoplasm shows histological characteristic solid and pseudopapillary proliferation. Immunohistochemistry detects, among the causes of tumor development, a correlation between the Beta-catenin mutations, alteration of the E-cadherin. In the most cases, therapy is surgical treatment with laparoscopic.

Clinicopathologic features of solid pseudopapillary pancreatic neoplasms in an Eastern Caribbean population

Pancreatic solid pseudopapillary neoplasms (SPNs) are uncommon lesions across the globe. Their incidence is unknown in the Caribbean. This retrospective study sought to document the clinicopathologic features of pancreatic SPNs in an Eastern Caribbean population. We examined data from the hospital records of all patients with SPN in Trinidad and Tobago, finding 11 cases over five years, equating to an incidence of 0.17 cases per 100,000 population per year. The lesions occurred in girls and young women at a mean age of 25 years, with a propensity for those of Afro-Caribbean descent. Poor prognostic factors (histologic invasion of the capsule, lymphovascular invasion, spindle cells, anaplastic cells and/or excessive mitotic figures) were present in 82% at the time of diagnosis. These tumours are uncommon in our population, and since most have poor prognostic features at diagnosis, we advocate an aggressive surgical approach.

Solid Pseudopapillary Tumor of the Pancreas: An Unusual Cause of Abdominal Pain

Solid-pseudopapillary neoplasm (SPN) of the pancreas is a rare tumor that accounts for less than one percent of pancreatic tumors. The diagnosis could be challenging as SPN tend to manifest with nonspecific abdominal symptoms, variable radiological features, and inconsistent morphology. The cellular origin of SPN is unclear and might involve ductal, acinar and endocrine stem cells. 

We report a rare case of a 27-year-old female who presented with intermittent abdominal pain for two years, associated with a decrease in appetite. Her medical history was significant for abdominoplasty five years ago. Vital signs were stable. Physical examination revealed mild epigastric tenderness. Laboratory tests were unremarkable. Contrast computed tomography (CT) scan of the abdomen showed a 2 x 2 cm indeterminate pancreatic tail lesion. An endoscopic ultrasound (EUS) disclosed a 2.1 x 1.8 cm hypoechoic mass in the tail of the pancreas.Trans-gastric fine needle aspiration was obtained to show clusters of uniform neoplastic cells with abundant cytoplasm and oval bean-shaped nuclei. Immunohistochemical stains were positive for beta-catenin, Vimentin, CD10, CD56, cytokeratin-7 (Ck7), Cyclin D1, and negative for chromogranin, epithelial-cadherin (E cadherin) which was consistent with a pseudopapillary tumor. The patient underwent a robotic assisted en-bloc distal pancreatectomy and splenectomy. There were no intra-abdominal metastases.

SPN is a rare tumor characterized by a specific immunohistological pattern which makes it highly distinct from other pancreatic neoplasms particularly neuroendocrine tumors, acinar carcinomas, and carcinoids. It is important to differentiate SPN from other pancreatic neoplasms because it is characterized as low potential for malignancy and a favorable prognosis after resection, with a five-year survival rate approaching 85%-95%.

Solid pseudopapillary tumor of the pancreas: clinical-pathological features and management of 13 cases

Background and aim

Solid pseudopapillary tumor (SPT) of the pancreas is a rare pathological condition, representing less than 3% of all exocrine pancreatic tumors. SPT usually occurs in young females, without notable symptoms, with a low malignant potential and excellent prognosis.

Method

We conducted a retrospective study during the period January 2005 – January 2015. SPT patients admitted in our institution were reviewed by describing demographic data, clinico-pathologic and radiological features, therapeutic management and prognosis records.

Results

Thirteen patients with SPT were identified (10 females), with a median age of 30 years. The main clinical presentation was abdominal pain (92.3%). The tumor was mostly located in the body or tail of the pancreas (77%), and the mean size was 8.2 cm. Regarding the surgical approach there were 5 distal pancreatectomies with splenectomy, 3 body and tail pancreatectomies, 2 body and tail pancreatectomies with splenectomy, 2 pancreato-duodenectomy, 1 partial enucleation and of all only 2 partial resections. Postoperative hematoxylin- eosin staining and immunohistochemistry confirmed the diagnosis in all cases. None of the patients had lymph nodes metastases. Only one local invasion. There was one case of death due to postoperative complications. Four cases followed adjuvant systemic chemotherapy. The mean follow-up was 18 months, without evidence of recurrence during this period.

Conclusion

SPT should always be considered in the differential diagnosis in young women with a pancreatic tumor. Complete surgical excision is the treatment of choice, and is usually curative. The decision to administer systemic therapy must be individualized. Malignant behavior and late recurrences mandates long-term follow-up for patients with SPT.

Pancreatoblastoma an Unusual Occurrence of a Tumour in Paediatric Age Group: A Case Report

Pancreatoblastoma, is rare exocrine malignant tumour of childhood. We are reporting a case of three-year-old child presented to our hospital suffering from vague abdominal pain for further examination and treatment. Clinical examination revealed only a palpable abdominal mass. CT Scan revealed a huge complex space occupying lesion 9.1x8.8x9.2cm with large central cystic degeneration and lobulated enhancing peripheral solid components with foci of calcification, seem to arise from body and tail regions of pancreas. Surgery was done and mass was removed. By histopathology and immunohistochemistry it was diagnosed as pancreatoblastoma. The prognosis is very good in paediatric age, lacking evidence of metastatic disease at first presentation. Therefore early diagnosis is needed for specific treatment. The case is being reported because of its rarity.

Clinical outcomes for 14 consecutive patients with solid pseudopapillary neoplasms who underwent laparoscopic distal pancreatectomy

INTRODUCTION

The postoperative results of laparoscopic distal pancreatectomy for solid pseudopapillary neoplasm of the pancreas (SPN), including the effects of spleen-preserving resection, are still to be elucidated.

METHODS

Of the 139 patients who underwent laparoscopic pancreatectomy for non-cancerous tumors, 14 consecutive patients (average age, 29.6 years; 1 man, 13 women) with solitary SPN who underwent laparoscopic distal pancreatectomy between March 2004 and June 2015 were enrolled. The tumors had a mean diameter of 4.8 cm. Laparoscopic spleen-preserving distal pancreatectomy was performed in eight patients (spleen-preserving group), including two cases involving pancreatic tail preservation, and laparoscopic spleno-distal pancreatectomy was performed in six patients (standard resection group).

RESULTS

The median operating time was 317 min, and the median blood loss was 50 mL. Postoperatively, grade B pancreatic fistulas appeared in two patients (14.3%) but resolved with conservative treatment. No patients had postoperative complications, other than pancreatic fistulas, or required reoperation. The median postoperative hospital stay was 11 days, and the postoperative mortality was zero.None of the patients had positive surgical margins or lymph nodes with metastasis. The median follow-up period did not significantly differ between the two groups (20 vs 39 months, P = 0.1368). All of the patients are alive and free from recurrent tumors without major late-phase complications.

CONCLUSION

Laparoscopic distal pancreatectomy might be a suitable treatment for patients with SPN. A spleen-preserving operation is preferable for younger patients with SPN, and this study demonstrated the non-inferiority of the procedure compared to spleno-distal pancreatectomy.

A Persistent Solid Pseudopapillary Tumor of the Pancreas: Case Report and Brief Literature Review

Background: Solid pseudopapillary tumors (SPTs) of the pancreas are uncommon neoplasms, first reported in 1934, well described by Frantz in 1959, and later further characterized by Hamoudi in 1970. Ninety percent of these tumors occur in young females in their second to third decade of life. An interesting case of a persistent solid pseudopapillary neoplasm is described in this report. Case presentation: A 24-year-old woman from a Middle Eastern country presented with an 8.2 × 7.6 cm heterogeneous-enhancing lesion growing within the uncinate process of the pancreas. She had first experienced symptoms at the age of 12 years. Imaging studies showed that the mass closely abutted the superior mesenteric vein as well as the superior mesenteric artery (SMA). The patient underwent an open cholecystectomy and a classic pancreaticoduodenectomy. During the resection, the SMA was transected due to tumor adherence. The vessel was subsequently reapproximated in an end-to-end manner. On the first postoperative day, thrombosis of the SMA occurred and a bile leak developed. The patient returned to the operating room for SMA embolectomy and for repair of a hepaticojejunostomy leak, with redo of the biliary-enteric anastomosis. Histopathological examination showed solid pseudopapillary-arranged cells and cystic areas, showing strong cellular immunoreactivity for CD56, CD10, vimentin, and β-catenin, and weak diffuse staining for synaptophysin. The tumor stained negative for chromogranin A, trypsin, AE1/AE3, and E-cadherin. Molecular genetic analysis was negative for the MYB gene deletion. At nearly 1 year of follow-up, the patient is well with no evidence of tumor recurrence. Conclusion: SPTs of the pancreas should be included in the differential diagnosis of pancreatic tumors, especially in young women.

Laparoscopic Distal Pancreatectomy with or without Preservation of the Spleen for Solid Pseudopapillary Neoplasm

Solid pseudopapillary neoplasm (SPN) is a rare tumor of the pancreas. Laparoscopic distal pancreatectomy (DP) is a feasible and safe procedure, and successful spleen preservation rates are higher using a laparoscopic approach. We hypothesized that certain patients with SPN would be good candidates for laparoscopic surgery; however, few surgeons have reported laparoscopic DP for SPN. We discuss the preoperative assessment and surgical simulation for two SPN cases. A simulation was designed because we consider that a thorough preoperative understanding of the procedure based on three-dimensional image analysis is important for successful laparoscopic DP. We also discuss the details of the actual laparoscopic DP with or without splenic preservation that we performed for our two SPN cases. It is critical to use appropriate instruments at appropriate points in the procedure; surgical instruments are numerous and varied, and surgeons should maximize the use of each instrument. Finally, we discuss the key techniques and surgical pitfalls in laparoscopic DP with or without splenic preservation. We conclude that experience alone is inadequate for successful laparoscopic surgery.

Retrospective analysis of short term outcomes after spleen-preserving distal pancreatectomy for sodid pseudopapillary tumours. Int J Surg. 2015;21 Suppl 1:S26-S29. [PMID: 26118599 DOI: 10.1016/j.ijsu.2015.06.047]

Solid pseudopapillary pancreatic tumour (SPN) is a rare pancreatic tumour representing 0.1%-3% of all exocrine pancreatic tumours. Most SPN show benign and low-grade malignant behaviour; malignant degeneration is observed in 10-15% of the patients. More than 40% of SPN involve the tail of the pancreas leading to a minimal invasive distal pancreatectomy approach. In this report we present the case of a young 22 Caucasian woman suffering from SPN who successfully underwent laparoscopic spleen-preserving distal pancreatectomy. Postoperative course was uneventful. A CT scan control at six months was negative for recurrences. We have also made an analysis of all the laparoscopic treatment of SPN reported in English literature.

Solid pseudopapillary neoplasm collides with a well-differentiated pancreatic endocrine neoplasm in an adult man: case report and review of histogenesis

OBJECTIVES

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare, clinicopathologically distinct neoplasm with a tendency to affect young women. The histogenesis of SPN is not well defined. Pancreatic endocrine neoplasms (PENs) are also uncommon tumors of the pancreas.

METHODS

Our comprehensive review of the literature did not yield any reported cases of collision tumors of the above two neoplasms. We report a case of such a collision tumor in a 45-year-old man.

RESULTS

This tumor was an incidental finding on computed tomography, followed by fine-needle aspiration confirmation of a tumor that was initially diagnosed as an SPN only. A histologic examination of a 2.1-cm mass following distal pancreatectomy revealed a 0.7-cm PEN partly engulfed by an SPN. The tumors showed different morphologic and immunohistochemical features, confirming the presence of a collision tumor.

CONCLUSIONS

A comparative analysis of immunoprofiles of these tumors yielded interesting findings, enabling us to postulate that SPNs may originate from a multipotential primordial cell that may follow different differentiation pathways, such as endocrine, epithelial, and acinar. The ultrastructures and immunophenotypic characteristics appear to support this hypothesis.

Laparoscopic central pancreatectomy for solid pseudopapillary tumors of the pancreas: our experience with ten cases

Background

Solid pseudopapillary tumors (SPTs) of the pancreas are a rare neoplasm. There are few reports of laparoscopic central pancreatectomies (LCPs) for SPT of the pancreas. The objective of this study was to evaluate the feasibility, safety and long-term outcome of LCP based on a series of SPT patients.

Methods

This retrospective study included ten patients who underwent LCP between 2009 and 2013. Clinical characteristics and intra- and postoperative data were retrospectively analyzed. A follow-up of at least 3 months was available for all patients.

Results

All procedures were successfully performed laparoscopically, and no patient required intraoperative blood transfusion. The median operative time was 271 min (range 250 to 310 min) and the median loss of blood was 104 ml (range 80 to 150 ml). The mean tumor size was 51 mm (range 38 to 62 mm). All patients underwent complete resection with negative surgical margin. An average of 5.8 lymph nodes were resected without metastases. The median first flatus time was 2 days, and the median starting time for diet was 3 days. The median postoperative hospital stay was 13 days (range 10 to 23 days). Morbidity was 20%. The median follow-up was 22.9 months (range 3 to 48 months), at which point all patients were alive with no recurrence. None of the patients developed exocrine or endocrine insufficiency. No hospital mortalities occurred in our patient group.

Conclusions

LCP is a safe and effective technique for resecting SPT of the neck and proximal body of the pancreas while preserving pancreatic endocrine and exocrine function, and the spleen.

Long-term follow-up after pancreatoduodenectomy with portal vein resection for a huge solid pseudopapillary neoplasm in an adolescent girl

A 16-year-old Japanese girl with a huge 13-cm-diameter tumor in the pancreas head presented with life-threatening symptoms and findings including severe anemia, obstructive jaundice, duodenal stenosis, and serious portal vein compression. She underwent a pancreatoduodenectomy with combined resection of the portal vein. Reconstruction of the portal vein was successfully performed using an external iliac vein graft and postoperative anticoagulant therapy. Pathological examination revealed a solid pseudopapillary neoplasm of the pancreas. The patient's postoperative course was uneventful, but her menstruation ceased for 14 months. She is now alive with no evidence of recurrence 100 months postoperatively and she suffers no impairments in daily activities of life. As a treatment of solid pseudopapillary neoplasms of the pancreas, pancreatoduodenectomy combined with portal vein resection is rarely performed in adolescent patients, but is reportedly successful, with patients tolerating the operation and surviving without recurrence. An aggressive surgical attitude is recommended when dealing with this tumor type with curative resection, even in adolescent patients.

Laparoscopic pylorus preserving pancreaticoduodenectomy in paediatric age for solid pseudopapillary neoplasm of head of the pancreas - case report

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare tumour commonly seen in young women without significant clinical features. SPN is usually a lowgrade malignant neoplasm which warrants resection. Recurrence and metastasis is seen rarely after complete resection. Pancreaticoduodenectomy is indicated for SPN situated in head of the pancreas which is generally performed by open approach. Laparoscopic pancreaticoduodenectomy (LPD) is difficult to perform for this condition because of smaller size of pancreatic and hepatic ducts more so in paediatric population. We report a case of 12 years old girl having SPN arising from head of the pancreas. She underwent laparoscopic pylorus preserving pancreaticoduodenectomy. Post-operative period was uneventful. Histological examination of resected specimen confirmed diagnosis of SPN. At 6 months follow up, she was doing well without any recurrence. To best of our knowledge, no case of LPD in paediatric patients is reported in literature available to us.

Solid pseudopapillary neoplasms of the pancreas: a report of two cases

Solid pseudopapillary neoplasms of the pancreas are uncommon, accounting for only 1-2% of all pancreatic neoplasms. These tumors are being detected at an increased rate, probably due to the increased awareness and the liberal use of imaging. We report two cases of patients with solid pseudopapillary pancreatic tumors and review the existing literature.

Solid pseudopapillary tumour (Frantz's tumour) of the pancreas in childhood

An 11-year-old girl presented with acute pancreatitis and mass in the head of the pancreas. MRI revealed a heterogeneous right-upper quadrant retroperitoneal mass measuring 6.8×6.1×5.5 cm arising from the pancreatic head. Endoscopic ultrasound with fine-needle aspirate revealed a solid pseudopapillary tumour (SPT) of the pancreas. The patient underwent a pylorus-preserving Whipple procedure. Pathology confirmed SPT. First described by Frantz, SPT represents less than 3% of all exocrine tumours. It is especially rare in children and shows different clinical features compared with adults. In our patient, tumour cells were arranged at the periphery of fibrovascular cores, but they did not show definite gland formation, keratinisation or cytoplasmic pigment accumulation. A periodic acid-Schiff stain without diastase did not show appreciable glycogen within the tumour cells, classic for Frantz's tumour. The literature, diagnosis, management and pathogenesis on this rare entity in children are reviewed and discussed.

Solid-pseudopapillary neoplasm of the pancreas: cytomorphologic findings and literature review

BACKGROUND

Solid-pseudopapillary neoplasm (SPN) is a rare pancreatic malignancy with an excellent prognosis. It is most commonly diagnosed in young women. This article comprehensively reviews the clinical, pathological and radiological features of this neoplasm, as well as its clinical management.

METHODS

A literature review of SPN was performed of all articles published in the English language in PubMed prior to November 1, 2013. Cytomorphological features, histopathology, immunohistochemistry, patient general demographics, molecular studies, radiologic imaging and clinical management were reviewed.

RESULTS

SPN displays distinct cytomorphological features on fine-needle aspiration - thin, delicate, branching vessels in a 'Chinese character' pattern lined by one to several layers of loosely cohesive neoplastic cells. Nuclear features include indented or grooved nuclei with an evenly distributed chromatin pattern and small inconspicuous nucleoli. SPN is characteristically immunoreactive for CD10, β-catenin (in an abnormal nuclear pattern), CD99 in a perinuclear dot-like pattern, α1-antitrypsin, and progesterone receptor. Almost all SPNs harbor an activating point mutation in exon 3 of the β-catenin gene (CTNNB1). Clinicopathological features generally do not correlate with prognosis, and most patients experience excellent long-term survival.

CONCLUSIONS

SPN can mimic other neoplasms of the pancreas, which can lead to diagnostic challenges in a limited cytologic specimen. Distinct cytomorphological features can help distinguish SPNs from other pancreatic neoplasms. Complete surgical resection as well as resection of metastatic disease is preferred given a low rate of tumor recurrence and long periods of disease-free intervals.

Role of laparoscopic distal pancreatectomy for solid pseudopapillary tumor

BACKGROUND

Since the first case report regarding laparoscopic distal pancreatectomy (DP) for solid pseudopapillary tumor (SPT), few additional articles have been published. The objective of this study was to evaluate the feasibility, safety, and long-term outcome of the laparoscopic DP based on a series of adult SPT patients.

METHODS

In a single-center study, we screened all adult patients undergoing a laparoscopic DP for SPT. Preoperative, operative, and postoperative data were retrospectively analysed and compared to the results of open DP for SPT published in the medical literature.

RESULTS

From April 2000 to June 2010, 5 adult female patients (median age 34 y) underwent a laparoscopic DP for an SPT. No conversion to open surgery was required. The median size of the tumor was 45 mm. The postoperative mortality rate was 0%, and serious complications (Dindo IV) occurred in 2 patients. The postoperative quality of life was not significantly altered by the laparoscopic procedure. At a median follow-up of 60 mo, all patients were alive and without evidence of local recurrence, distant metastasis, diabetes, or exocrine insufficiency.

CONCLUSION

Laparoscopy may offer an alternative to open surgery in the treatment of SPT of the distal pancreas in adult female patients. The laparoscopic procedure impacts neither the oncologic outcome nor the quality of life. However, due to the risk of postoperative complications, this procedure should be reserved for specialized centers.

Solid pseudopapillary tumour of the pancreas: Incidence, prognosis and outcome of surgery (single center experience)

BACKGROUND

Solid pseudopapillary tumour (SPT) of the pancreas is a rare neoplasm of low malignant potential. The pathogenesis and guidelines for its treatment remain unclear. This study was designed to evaluate the diagnosis, surgical treatment and prognosis of SPT.

STUDY DESIGN

A retrospective study during the period between January 1995 to October 2012.

PATIENTS AND METHOD

Cases with SPTs treated at our institution were reviewed. Demographic data, clinical manifestations, radiological, surgical, and pathological records were reviewed for patients with SPT.

RESULTS

Twenty four patients with SPT were identified (22 women and 2 men with a mean age 24.83 ± 8.66 (12-52 years). The tumour was located in the head in (50%) and in the body (8.3%) and in the tail (41.7%). The mean size was 9.2 ± 5.3 (3-25 cm). The main clinical presentation was abdominal pain in (83.3%). All 24 patients had curative resection including pancreaticoduodenectomy (50%), central pancreatectomy (8.3%) and distal pancreatectomy (41.7%). Sex, age, symptoms, tumour size, CT image and tumour markers were not significant clinical factors to predict SPT with malignant behavior. The recurrence rate was (8.3%) after 5 years postoperatively. No hospital mortality, all patients except 2 patients (8.3%) were alive at follow up period. The estimated 1, 3, and 5 year survival rate was 95%, 95%, and 88%.

CONCLUSION

SPT are rare neoplasms with malignant potential. Aggressive surgical resection is needed even in presence of local invasion, and also for recurrence as patients had a good long term survival.

Cercariform cells: another cytologic feature distinguishing solid pseudopapillary neoplasms from pancreatic endocrine neoplasms and acinar cell carcinomas in endoscopic ultrasound-guided fine-needle aspirates

BACKGROUND

Solid pseudopapillary neoplasm (SPPN) is a rare tumor of unknown origin that occurs predominantly in the body or tail of the pancreas in young women. The authors recently identified cercariform (Greek: tailed) cells, similar to those described in urothelial carcinomas, as a consistent cytologic feature in ultrasound-guided fine-needle aspiration (EUS-FNA) samples from SPPNs. The objective of the current multi-institutional study was to define the value of these cells in the differential diagnosis of SPPN with other neoplasms characterized cytologically by the presence of monotonous, uniform cells in pancreatic aspirates: pancreatic neuroendocrine tumors (Pan-NETs) and acinar cell carcinomas (ACCs).

METHODS

The files of 4 academic hospitals were searched for SPPNs, Pan-NETs, and ACCs that were diagnosed by EUS-FNA. The slides were reviewed, and several cytologic features were recorded semiquantitatively to identify discriminating features between SPPNs, Pan-NETs, and ACCs.

RESULTS

From the analysis of 18 SPPNs, 4 ACCs, and 20 Pan-NETs, the following cytologic features were identified as common to all 3 neoplasms: single cells and rosettes/acinar cell groups, round-to-plasmacytoid cells, pale-to-granular cytoplasm, fine vacuoles, and binucleated cells. Papillary structures, cercariform cells, large cytoplasmic vacuoles, reniform nuclei, hyaline globules/magenta-colored material, and degenerative features (cholesterol crystals, calcifications, foam cells, or giant cells) were significantly more common in SPPNs. Prominent nuclear grooves were encountered in only 4 of 18 SPPNs.

CONCLUSIONS

The current results indicated that the presence of cercariform cells is another useful clue for the cytologic diagnosis of SPPN in challenging cases.

Solid pseudopapillary tumor of the pancreas: a single-institution 20-year series of pediatric patients

PURPOSE

Solid pseudopapillary tumor (SPT) of the pancreas is a rare neoplasm. The objective of this study was to review our institution's experience and provide an update on current management in the pediatric population.

METHODS

Our pathology database identified all patients with SPT for a 20-year period (1991-2011). Demographics, clinical characteristics, operative details, pathology, and outcomes data were retrospectively reviewed.

RESULTS

Eleven patients with SPT were identified. Most were female and Hispanic. Median age at resection was 14 years (9-17 years). Most patients presented with abdominal pain. Diagnostic imaging was most commonly an ultrasound or computed tomography. All tumors were resected en bloc. Median greatest tumor diameter was 5 cm (3.5-12 cm). Median length of stay was 8 days (5-19 days). Complications included pancreatic leak, chyle leak, delayed gastric emptying, fat malabsorption, and incisional keloid. Recurrence developed after 2.5 years in 1 patient with positive surgical margins. There were no metastases or deaths. Median follow-up was 1.4 years (0.6-5.9 years).

CONCLUSION

This pediatric series of SPT from a single institution corroborates previous reports in the literature. In our experience, SPT behaves like a low-grade malignancy and has an excellent prognosis. Surgical resection is dictated by tumor location and remains the treatment of choice.

Pseudopapillary tumor in pediatric age: clinical and surgical management

BACKGROUND

Solid pseudopapillary tumors of the pancreas are rare exocrine pancreatic tumors. Through a review of pediatric cases in a single Institution, we present the clinical and surgical management of this neoplasm.

METHODS

We retrospectively reviewed the clinical charts of patients treated at our unit between 1995 and 2009 for SPT. Clinical and surgical management were analyzed and reported.

RESULTS

During the study period 11 patients underwent surgery for pseudopapillary tumor. Five patients were treated with duodenum-preserving pancreatic head resection and six patients with splenopancreasectomy with a Roux-en-Y pancreatic jejunostomy. Patients did not show recurrence and are currently disease free. Blood tests, Ultrasound, Computed tomography and Magnetic Resonance Imaging were not useful to preoperatively identify the nature of the pancreatic masses.

CONCLUSION

Solid pseudopapillary tumor is a rare condition that should be taken into account for the differential diagnosis of pancreatic masses in pediatric age. Due to its favourable prognosis, surgical removal should be planned and done following the intraoperative findings.

Solid pseudopapillary neoplasms of the pancreas

SPN is a rare neoplasm that affects mainly young women. Despite this feature, SPN have been seen in both genders, multiple races, and at a wide range of ages. The genetic mechanism behind the development of SPN is distinct from the more lethal ductal carcinoma of the pancreas. This difference is reflected in the favorable outcome for patients with SPN. Surgery is typically curative in patents with localized disease and possibly in patients with limited metastasis or local extension. No consensus exists on an effective systemic therapy. There are no reliable predictors for disease-specific mortality or recurrence in the minority of patients who develop aggressive disease.

Surgical management of solid-pseudopapillary neoplasms of the pancreas (Franz or Hamoudi tumors): a large single-institutional series

BACKGROUND

Solid-pseudopapillary neoplasms (SPNs) are rare pancreatic tumors with malignant potential. Clinicopathologic characteristics and outcomes of patients with SPN were reviewed.

STUDY DESIGN

Longterm outcomes were evaluated in patients with an SPN who were followed from 1970 to 2008.

RESULTS

Thirty-seven patients were identified with an SPN. Thirty-three (89%) were women, and median age at diagnosis was 32 years. Most patients were symptomatic; the most common symptom was abdominal pain (81%). Thirty-six patients underwent resection; one patient with distant metastases was not operated on. There were no 30-day mortalities. Median tumor size was 4.5 cm. Thirty-four patients underwent an R0 resection, 1 had an R1 resection, and 1 had an R2 resection. Two patients had lymph node metastases, and one patient had perineural invasion. After resection, 34 (94%) patients remain alive. One patient died of unknown causes 9.4 years after resection, and another died of unrelated causes 25.6 years after operation. The patient with widespread disease who didn't have resection died 11 months after diagnosis. Thirty-five of the 36 patients having resection remained disease free, including those who died of unrelated causes (median followup, 4.8 years). One patient developed a recurrence 7.7 years after complete resection. She was treated with gemcitabine and remains alive 13.6 months after recurrence.

CONCLUSIONS

SPNs are rare neoplasms with malignant potential found primarily in young women. Formal surgical resection may be performed safely and is associated with longterm survival.

Solid pseudopapillary neoplasms of the pancreas: a multi-institutional study of 21 patients. J Surg Res. 2009;157:e137-e142. [PMID: 19818965 DOI: 10.1016/j.jss.2009.03.091]

BACKGROUND

Solid pseudopapillary neoplasms of the pancreas (SPN) account for less than 1% of all pancreatic tumors. The goal of this study was to better understand the nature of these rare tumors through analysis of patients' clinical presentations and outcomes following surgical resection.

METHODS

A multi-institutional retrospective review was conducted of all patients who underwent surgical resection from 1994 to 2008.

RESULTS

Twenty-one patients were identified with SPN. Twenty patients were female. Median age at presentation was 34 y. The most common presenting symptom was abdominal pain (67%). All patients underwent resection: distal pancreatectomy (9), pancreaticoduodenectomy (5), central pancreatectomy (6), and laparoscopic excision/enucleation (1). A R(0) resection was obtained in all patients. Median tumor size was 5.5 cm. AJCC stages were stage I (18), stage II (1), stage III (2), and stage IV (0). Postsurgical complications occurred in 52% of patients, with pancreatic fistulae being the most common (29%). The median follow-up time was 55 mo. All patients remain alive without evidence of recurrence.

CONCLUSION

Solid pseudopapillary neoplasms of the pancreas are atypical pancreatic tumors. SPN usually occur in young women who present with abdominal pain. Oncologic outcomes in patients who undergo surgical resection are excellent.

Management of solid-pseudopapillary neoplasms of the pancreas: a comparison with standard pancreatic neoplasms

Background

Solid-pseudopapillary neoplasms (SPNs) of the pancreas are increasingly diagnosed, but the exact surgical management in terms of extent of the resection is not well defined.

Materials and Methods

Patients operated on in our hospital between January 1993 and March 2005 formed the study groups.

Results

From 659 consecutive resections for pancreatic neoplasms, 12 female patients (1.8%) with a median age of 21 years who underwent resection for (SPN) are compared with the remaining 647 pancreatic resection patients. Jaundice (SPN 0 versus PR 73%, p < 0.001) and weight loss (SPN 0 versus PR 49%, p = 0.001) occurred significantly less often. Neoplasms were distributed equally among the pancreatic head (SPN 5 out of 12 patients versus PR 88%, p < 0.001) and corpus/tail (SPN 6 out of 12 patients versus PR 8%, p < 0.001). The operative time was significantly shorter (SPN 233 min versus PR 280 min, p = 0.012), and there were significantly fewer complications (SPN 1 of 12 patients versus PR 48%, p = 0.007). The mortality was not different (SPN 0 versus PR 1.6%, p = 1.000), and the hospital stay was significantly shorter (SPN 9 days versus PR 15 days, p = 0.012). The median size of the neoplasms was significantly larger (SPN 6.9 cm versus PR 2.5 cm). The median number of lymph nodes harvested was significantly fewer (SPN 1 versus PR 6, p = 0.001), and lymph node metastases occurred significantly less often (SPN 0 versus PR 64%, p < 0.001). The 5-year survival of SPN patients was 100% and is significantly better compared with survival of patients with pancreatic adenocarcinoma (12%, p < 0.001) and ampulla of Vater adenocarcinoma (22%, p = 0.005).

Conclusions

Patients with solid-pseudopapillary neoplasms of the pancreas present differently and the course of the disease is more benign. These patients can be adequately managed by pylorus-preserving pancreatoduodenectomy or spleen-preserving distal pancreatectomy with excellent early and long-term results.

Non-resected solid papillary epithelial tumor of the pancreas: 18F-FDG PET/CT evaluation at 5 years after diagnosis

Solid and papillary epithelial neoplasm of the pancreas (SPEN) is an encapsulated, slowly enlarging abdominal mass that generally shows no evidence of capsular invasion, regional lymph node involvement, or distal metastases. We present a 68 years old Hispanic male diagnosed with SPEN 5 years earlier that refused surgical excision. Presently he underwent a whole-body 18F-FDG PET/CT. Although tumor size, location and CT features did not seem to depict significant changes, FDG-PET was useful showing persistent tumoral activity. A brief review of the differential diagnosis as well as the usefulness of FDG-PET in SPEN (a slow growing pancreatic neoplasm) is presented.

Nonductal neoplasms of the pancreas

Although the majority of pancreatic neoplasms are infiltrating ductal adenocarcinomas or other neoplasms with ductal differentiation, neoplasms with acinar, endocrine, mixed, or uncertain differentiation constitute a diverse and distinctive group. The most common and best-characterized nonductal neoplasms are pancreatic endocrine neoplasm, acinar cell carcinoma, pancreatoblastoma, and solid pseudopapillary neoplasm. This review details the clinical and pathologic features of these nonductal neoplasms, highlighting diagnostic criteria including the use of specific immunohistochemical stains to define the cellular differentiation of the neoplasms.