Solid and Pseudopapillary Tumor of the Pancreas—Review and New Insights Into Pathogenesis

Solid pseudopapillary neoplasm (SPN) of the pancreas: current understanding on its malignant potential and management

Solid pseudopapillary neoplasms (SPN) of the pancreas are presently recognized as low-grade malignant tumors that are frequently observed in young females. This tumor has a low incidence and is associated with an excellent prognosis following surgical resection. Typical SPNs primarily affect the pancreas and tend to have moderate or asymptomatic manifestations. Based on retrospective research, it is anticipated that patients with SPN can achieve disease-free survival, even in cases when metastasis is detected during inspection. However, the incidence of malignant SPN has been consistently underestimated, as evidenced by recent research findings. Malignancy of SPN primarily encompasses invasion and infiltration, metastasis, and recurrence after R0 resection. Imaging technologies such as Ultrasound, Computed Tomography, Magnetic Resonance Imaging, and Position Emission Tomography are capable of preliminarily identifying malignant SPN, which is primarily based on its invasive clinical features. Research on risk factors of malignant SPN revealed that larger tumor size, Ki-67 index, and several other parameters had significant correlations with invasive tumor behavior. Pathologic features of malignant SPNs overlay other pancreatic tumors, nevertheless they can provide valuable assistance in the process of diagnosis. Several confirmed specific pathologic biomarkers are related to its cellular origin, characteristic gene mutation, and cell proliferation. Considering the invasiveness of malignant SPN, it is imperative to enhance the comprehensiveness of its therapy. Tumor resection remains a suggested course of action in line with typical SPN, and additional lymph node dissection is seen as reasonable. Compared to benign SPNs, malignant SPNs have worse prognosis, underscoring the necessity of early identification and treatment in comprehensive medical centers to get improved clinical outcomes.

Spontaneous regression in solid pseudopapillary neoplasm of pancreas

A solid pseudopapillary neoplasm (SPN) of the pancreas is a rare neoplasm that mainly occurs in young women. We herein report the case of spontaneous regression in SPN of the pancreas. A 48-years-old female was found to have a mass in the head of the pancreas on examination for her back pain and referred to our hospital in 20XX. Laboratory data showed no abnormalities in serum levels of pancreatic enzymes and tumor markers. A contrast CT scan of upper abdomen showed a slightly enhanced lesion (23 × 19 mm in diameter) without cystic component or fibrous capsule in the head of the pancreas. An MRI scan showed the mass as low-intensity in T1-WI and high-intensity in T2-WI. She admitted to our hospital for further examination of a pancreatic mass by EUS-FNA in 20XX + 4. EUS showed a slightly hypoechoic mass (30 × 19 mm in diameter) compared with the neighboring normal pancreas. Tumor margin was relatively clear and the internal echo image was homogenous. Histological findings revealed a solid and pseudopapillary proliferation of eosinophilic polygonal cells with oval nuclei. The tumor cells were positive for vimentin and CD10 in the cytoplasm and β-catenin in the nuclei, which led to the diagnosis of SPN. We recommended this patient to undergo surgical resection, however, the patient chose follow-up examinations. Follow-up study after 1 year using MRI scan showed spontaneous regression, which was coincided with her menopause. These findings suggest that the natural regression of SPN may occur and female sex hormone changes may regulate the growth of SPN.

Pancreatic Cystic Tumors: A Single-Center Observational Study

Background and Objectives: The aim of the study was to analyze the prevalence and characteristics of pancreatic cystic tumors (PCTs). Material and Methods: A retrospective analysis of the medical records of 124 patients, 102 (69%) women and 46 (31%) men, who had undergone surgery for pancreatic cystic tumors in 2014-2018. Among 148 pancreatic cysts, 24 (16%) were non-neoplasmatic and 124 (84%) were neoplasmatic. The neoplasmatic cysts (n = 124) were included in our analysis. There were five main types of PCTs: IPMN (intraductal papillary mucinous neoplasm) (n = 45), MCN (mucinous cystic neoplasm) (n = 30), SCN (serous cystic neoplasm) (n = 28), SPN (solid pseudopapillary neoplasm) (n = 8), and CPEN (cystic pancreatic endocrine neoplasm) (n = 8), as well as mixed-type tumors (n = 5). Results: A statistically significant dependency between PCT type and age was proven (p= 0.0001): IPMNs were observed in the older group of patients with an average age of 66.12 (40-79) years while SPNs were noted in the youngest group of patients with an average age of 36.22 (22-55) years. A statistically significant association between PCT type and gender (p = 0.0001) was found: IPMNs occurred among 24 (53.33%) men and 21 (46.6%) women. In the MCN and SPN groups, all patients were female (100%). Among the SCN group, the majority were women (27 (96.43%)), and there was only 1 (3.57%) man. A statistically significant dependency between PCT type and size was proven (p = 0.0007). The mean size of IPMNs was the smallest 2.95 (0.6-10 cm) and the mean size of MCNs was the largest 6.78 (1.5-19 cm). A statistically significant dependency between PCT type and tumor location was proven (p = 0.000238). The most frequent location of IPMN was the pancreatic head: 27 (60%). MCN was most frequently located in the pancreatic tail (18 (60%)). Most (10/28) SCNs were found in the pancreatic tail (10 (35.71%)). CPENs were most frequently located in the pancreatic tail (three (37.5%)) and pancreatic body and tail (three (37.5%)). SPNs were located commonly in the pancreatic head (five (62.5%)). The type of surgery depended on the tumor location. The most frequent surgery for IPMNs was pancreatoduodenectomy (44.4%), while for MCNs and SCNs, it was distal pancreatectomy (81%). The postoperative morbidity and mortality were 34.68% and 1.61%, respectively. Postoperative pancreatic fistula (POPF) was the most frequent (29%) complication. Conclusions: IPMN was the most frequent resected PCT in our material. A statistically significant association between the type of cyst and location within the pancreas, size, local lymph node involvement, and patient's age and sex was proved. POPF was the most frequent postoperative complication. In patients with PCTs, due to substantial postoperative morbidity, adequate patient selection, considering both the surgical risk as well as the long-term risk of malignant transformation, is very important during qualification for surgery.

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.

Prognostic Enigma of Pancreatic Solid Pseudopapillary Neoplasm: A Single-Center Experience of 63 Patients

Background: Studies investigating prognostic factors of solid pseudopapillary neoplasm (SPN) have been published with conflicting findings.

Methods: Retrospective analysis of 63 consecutive cases of SPN in our institution from January 2010 to December 2019 was carried out. The clinicopathological features, treatment practices along with survival associations were collected and analyzed.

Results: Fifteen patients (23.8%) were male, and 48 (76.2%) were female, with a median age of 34.0 ± 14.5 years. The larger tumor size was correlated with the more mixed components (p = 0.000) and the higher Ki-67 index (p = 0.042). No recurrence was found in the nine patients whose tumors fulfilled the WHO criteria for malignancy due to the presence of at least perineural invasion (6.4%), angiovascular invasion (2.3%), and/or adjacent organ invasion (6.4%). Microscopic infiltrative growth was detected in 9 (14.3%) tumors, which was correlated significantly with the WHO criteria (p = 0.002), capsule invasion (p = 0.005), and pancreatic parenchyma invasion (p = 0.001), but not with disease-free survival (p = 0.13). CD99 was found to be positively expressed in 88.9% (40/45) of tumors and more likely to have depressed Ki-67 index (p = 0.016). After a median follow-up of 58 months, only two patients (3.2%) had a recurrence after their first operation outside of our hospital. No patient died due to tumor progression.

Conclusions: Although survival is favorable with aggressive surgery, it is actually difficult to assess the prognostic factors of resected SPNs. Future investigations into the role of clinicopathological evaluation will unveil the prognostic enigma of pancreatic SPN after resection.

Molecular Alterations in Solid Pseudopapillary Neoplasm of the Pancreas: The Achilles Heel in Conquering Pancreatic Tumorigenesis

Solid pseudopapillary neoplasms of the pancreas are overwhelmingly benign tumors predominately observed in women in the third decade of life. However, their malignant potential, based on local recurrences and metastases, has brought into question the available evidence on their biological behavior. Solid pseudopapillary neoplasms have distanced themselves from other pancreatic tumors with varying morphological appearance, immune profile, and histogenesis. In review of the literature, PubMed was queried using search strings, including "solid pseudopapillary neoplasm" and "molecular," and "immunohistochemistry." Alternative searches were also conducted given the variability in tumor name, including "solid pseudopapillary tumor" and "Frantz tumor." This article provides an in-depth review into the molecular pathways that contribute to the pathogenesis of solid pseudopapillary neoplasms. It also discusses the implications of existing molecular pathways toward tumor aggressiveness and recurrence potential.

Lymphoid Enhancer Binding Factor 1 (LEF1) and Paired Box Gene 8 (PAX8): A Limited Immunohistochemistry Panel to Distinguish Solid Pseudopapillary Neoplasms and Pancreatic Neuroendocrine Tumors

Solid pseudopapillary neoplasms (SPNs) and pancreatic neuroendocrine tumors (PanNETs) are distinctive entities. However, due to overlapping morphologies, distinguishing them remains a diagnostic challenge. Our study investigates the utility of immunohistochemistry for nuclear lymphoid enhancer binding factor 1 (LEF1) and paired box gene 8 (PAX8) in differentiating these 2 entities. LEF1 and PAX8 immunohistochemistry were performed on fine-needle aspiration cell blocks and surgical resection specimens diagnosed as SPN or PanNET at our institution from January 2007 to August 2016. Eight SPN and 25 PanNET cell blocks and 17 SPN and 34 PanNET surgical resection specimens were examined. On cell blocks, positive staining for LEF1 had high frequency, sensitivity, and specificity for SPN (88%, 88%, and 88%) as did positive staining for PAX8 for PanNET (76%, 76%, and 75%). The findings on surgical resection specimens were consistent with those from cell blocks (LEF1+ in SPN: 100%, 100%, and 97%; PAX8+ in PanNET: 59%, 59%, and 100%). A combined LEF1+/PAX8- phenotype showed high sensitivity and specificity for SPN (cell block: 63% and 100%; surgical specimen: 100% and 98%) as did a LEF1-/PAX8+ phenotype for PanNET (cell block: 64% and 100%; surgical specimen: 59% and 100%). SPN and PanNET exhibit opposite immunophenotypic profiles with LEF1+/PAX8- in SPN and LEF1-/PAX8+ in PanNET. The combination of these 2 stains provides an effective means of distinguishing these 2 entities.

Solid pseudopapillary neoplasms of the pancreas: Case series with a review of the literature

BACKGROUND/AIMS

The solid pseudopapillary neoplasms are quite rare tumors of the pancreas, comprising roughly 1-2% of all pancreatic neoplasms. It has a low malignant potential and usually affects young females. Despite increasing number of articles in the last decade, there is still debate on the pathogenesis, malignant potential and optimal surgical strategy for the solid pseudopapillary neoplasms.

MATERIALS AND METHODS

Medical recordings of 326 patients who were operated due to pancreatic mass were retrospectively analyzed. Patient demographics, presenting symptoms, surgical and pathologic characteristics of the tumor, postsurgical course, long-term survival, and other relevant data were extracted from patients' charts.

RESULTS

Majority of the patients were female in consistency with the classic data in the literature. All the patients underwent curative intent resections. Tumors were commonly localized in the tail of the pancreas making distal pancreatectomy the most commonly performed surgical procedure. Mean tumor diameter was 5.8 centimeters with tumor sizes ranging from 1 to 19 cm.

CONCLUSION

The solid pseudopapillary neoplasms of the pancreas is a rare tumor with low malignant potential, which is more common in females of reproductive age, with abdominal pain being their most common presentation. The short-term outcomes in patients following surgical R0 resection are excellent. However, proximal placement of the tumor and female gender may have slightly worse prognosis. We hope that our findings from a series of patients represent a contribution to the existing literature on SPN, and authors declare their willingness to provide further details for future meta-analyses.

Pancreatic solid pseudopapillary neoplasm in male patients: systematic review with three new cases

Pancreatic solid pseudopapillary neoplasm (pSPN) is a rare exocrine neoplasm, which generally occurs in young women. This study analyses the clinical characteristics of pSPN in male patients through a systematic review of the literature, adding three new cases from our institution. We reviewed our experience in Pspns, and we performed a systematic review of pSPN of all articles published in English in PubMed and SCOPUS from 1980. Using the final included articles, we evaluated clinic-pathological features, surgical treatment and prognosis of male patients affected by pSPN. From the literature review and our cases, we collected 246 male patients with a proven pSPN. Mean age was 34.3 (range 4–78) years, with 26.2% patients younger than 18 years. Patients were asymptomatic in 35.9% of cases, despite a mean tumour size of 6.3 cm. In 63.7% of cases, the pSPN was located in the body–tail region. Distant metastases were reported at diagnosis in only 10 (4.1%) patients. A correct pre-operative diagnosis (including cytopathology) was provided in 53.6% of patients, with only 40 fine-needle aspiration/biopsy performed. Standard pancreatic resections represented 90.4% of surgical procedures. Beta-catenin and progesterone receptors were positive at immunostaining in 100% and 77.8% of cases, respectively. Fourteen (7.2%) patients relapsed after a mean disease-free survival of 43.1 months. After a mean follow-up of 47 (range 4–180) months, 89.5% of patients were alive and disease-free. Although rare, when dealing with a solid-cystic pancreatic mass, even in asymptomatic male patients, a pSPN should be considered as a possible diagnosis.

Fine needle aspiration cytology with the aid of immunocytochemistry on cell-block confirms the diagnosis of solid pseudopapillary neoplasm of the pancreas

INTRODUCTION

To determine the diagnostic efficacy of fine needle aspiration cytology (FNAC) in cases of pancreatic solid pseudopapillary neoplasm (PSPN) with emphasis on the cytomorphological features and to evaluate the contribution of immunocytochemistry on FNAC cell-block (CB) in cases of PSPN.

METHODS

It is a retrospective study in which ultrasound-guided FNAC of pancreatic lesions diagnosed as PSPN between years 2009 and July 2019 were reviewed along with cytohistological correlation. Immunocytochemistry on CB was performed, wherever required.

RESULTS

A total of 16 patients with a cytological diagnosis of PSPN of the pancreas were identified. The most common cytological findings were characteristic branching pseudopapillary fragments with central thin, delicate capillaries associated with the amorphous myxoid substance, surrounded by tumour cells with mild pleomorphism. Immunocytochemistry was performed on CB of six cases. The tumour cells revealed nucleocytoplasmic positivity for β-catenin, cytoplasmic positivity for vimentin, membranocytoplasmic positivity for CD10 and nuclear positivity for progesterone receptor in all the cases, while they were negative for chromogranin, CD56, pan-cytokeratin and epithelial membrane antigen. The resected histopathological specimen was available in 10cases, and all were confirmed as PSPN.

CONCLUSION

Although PSPN has a characteristic cytomorphology, cell-block immunocytochemistry on FNA material confirms the diagnosis in problematic cases and excludes other pancreatic tumours, thus helping in appropriate management.

Different Methods of Resection of Solid Pseudopapillary Neoplasm of the Pancreas: A Case Series of Three Patients

Solid pseudopapillary neoplasm of the pancreas is one of the rarest forms of pancreatic neoplasm. It was also known as Franz's tumor or Hamoudi tumor until the World Health Organization (WHO) labeled it as a solid pseudopapillary tumor in 1996. It typically affects young non-Caucasian females in their second or third decade of life. Treatment involves complete excision of the tumor which results in a complete cure in most of the cases. Three cases of solid pseudopapillary neoplasm (diagnosis confirmed by cytology) in young females, each presenting with different symptoms were studied. Each of the three cases was found to have the neoplasm at different sites of the pancreas and was subjected to different resection procedures. The cases were followed up for at least a year and evaluated for recurrences/metastases. Solid pseudopapillary neoplasm remains one of the most misdiagnosed tumors. The diagnosis depends on radiology and cytology. With a very high five-year survival rate, surgical resection remains the treatment of choice. The type of surgical procedure depends on the site, size and local invasion of the tumor.

Solid pseudopapillary neoplasm of the pancreas: a report of 10 cases and literature review

BACKGROUND

Solid pseudopapillary tumour of the pancreas (SPTP) is a rare pancreatic tumour characterized by a non-specific clinical presentations and vague radiologic features. The aim of this study is to identify these tumours from other pancreatic neoplasms because complete resection is curative in most cases and provides long-term survival.

METHODS

A retrospective analysis of patients operated for SPTP between January 2000 and December 2018 was conducted. The collected data included age, gender, clinical findings, laboratory tests, radiological findings, anatomopathological examination, immunohistochemistry results, surgical treatment, mortality, morbidity and recurrence.

RESULTS

Ten cases of SPTP have been diagnosed between January 2000 and December 2018 representing 5.1% of all pancreatic tumours operated during this period (male/female: 2/8; median age 41.2 years; range 19-78 years). The most common symptom was abdominal pain and physical examination was normal in four of 10 cases. The most common tumour localization was the tail of the pancreas. The main tumour size was 7.2 cm (range 2-15 cm). One patient had abdominal disseminated disease. Surgical interventions were distal pancreatectomy in five cases, enucleation in one case, cephalic duodeno-pancreatectomy in two cases, central pancreatectomy in one case and pancreatic biopsy in one case. Only one patient received adjuvant chemotherapy. During follow-up, one patient died after 12 months and another developed unique hepatic metastasis that was resected.

CONCLUSION

Although it is delayed in diagnosis, the overall prognosis of these tumours remains good even with local recurrence and metastasis. Complete surgical resection is the treatment of choice even in cases of recurrence.

Diagnosis and Surgical Treatment and Pathological Findings of Solid Pseudopapillary Tumor of the Pancreas: A Single-Institution Experience

Purpose

To investigate the diagnosis, surgical treatment, and pathology of solid pseudopapillary tumors of the pancreas in our institution.

Patients and Methods

We retrospectively analyzed the demographic details, clinical features, imaging findings, and pathological findings of 87 patients with a confirmed diagnosis of solid pseudopapillary tumors of the pancreas (SPTP) and underwent surgery in Tongji Hospital of Tongji Medical College, over a period of 8 years from 2011 to 2018.

Results

Our study involved a total of 87 patients (16 males and 71 females) with a mean age of 31.3±13.1 years (range: 10–61 years). The main compliant was abdominal pain or discomfort (n=49) and the median tumor size was 58.6±31.7 mm (range: 16–156mm). Tumors were located in the head (27 patients, 31%), the neck (13 patients, 15%), and the body and tail (47 patients, 54%). There were no significant differences between the patients in terms of sex, age, or tumor location. Partial pancreatectomy was performed in 79 patients, enucleation in six patients, and total pancreatectomy in two patients. R0 resection was achieved in 86 patients. The postoperative morbidity was 36.8%, and the main complication was pancreatic fistula. Pathological examination and immunohistochemical markers were used to provide a final diagnosis. The main follow-up period was 46 months (range: 13–97 months). At the end of the follow-up period, 86 patients were alive and had not experienced recurrence; one patient was lost to follow-up.

Conclusion

The accurate diagnosis of SPTP is vital. Our data showed that surgical resection is safe and associated with low morbidity and mortality rates. Pathological findings can play an important role in diagnosis and long-term survival.

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.

Prognostic value of progesterone receptor in solid pseudopapillary neoplasm of the pancreas: evaluation of a pooled case series

Background

The role of progesterone receptor (PR) has been reported in a series of pancreatic cysts. However, the relationship between PR and prognosis of solid pseudopapillary neoplasm of the pancreas (SPNP) has not been elucidated so far. The aim of our study was to evaluate the prognostic value of PR in SPNP.

Methods

A total of 76 patients with SPNP treated in our institution from January 2012 to December 2017 were included. Demographic parameters, laboratory data, pathologic information and clinical outcomes were analyzed by the use of survival analysis. In addition, a pooled case series was performed to evaluate the results.

Results

The institutional data included 76 patients (17 male and 59 female) ranging from 8 to 90 years (median, 30 years) in age. Kaplan-Meier survival analysis confirmed negative PR result was significantly associated with poorer disease-free survival (DFS) and disease-specific survival (DSS) (both P < 0.001). In the pooled analysis, a total of 62 studies comprising 214 patients with SPNP were included. After multivariable cox analysis, negative PR result remained an independent prognostic factor for SPNP (DFS HR: 14.50, 95% CI: 1.98–106.05, P = 0.008; DSS HR: 9.15, 95% CI: 1.89–44.17, P = 0.006).

Conclusion

Our results indicated the role of PR in predicting adverse outcome of patients with SPNP and negative PR result may serve as a potential prognostic factor.

Electronic supplementary material

The online version of this article (10.1186/s12876-018-0914-8) contains supplementary material, which is available to authorized users.

Retrospective evaluation of patients diagnosed solid pseudopapillary neoplasms of the pancreas

PURPOSE

Solid pseudopapillary neoplasm (SPN) is a rare, low-grade neoplasm with excellent prognosis. In this study, we evaluated clinicopathological characteristics of patients diagnosed with SPN retrospectively.

METHODS

This is a retrospective study intended to characterize patients with the diagnosis of SPN between 2005 and 2015. Clinicopathological features, recurrence rate, and overall survival of 28 patients were recorded. Malignant SPN criteria were defined as the presence of distant metastasis (developed at diagnosis or during follow up) or lymph node involvement.

RESULTS

The mean age at diagnosis was 42 (range: 17-41). Among patients, 82% (n = 23) were female and 17.9% (n = 5) were male. The mean size of tumor was 5.81 cm (range: 2-15). The mean follow up period was 55.6 months, 1-year survival was 96.5% and 5-year survival rate was 88%. A total of 25 patients were alive at the end of follow-up period and 3 of the patients became exitus due to disease. Two patients had a metastatic presentation in livers at the diagnosis and metastasis developed in 3 patients during follow-up (liver of 1 patient, peritoneum in 1 patient and liver and peritoneum in 1 patient). The reason of admission was headache in 68% patients. The type of operation was frequently subtotal pancreatectomy (n = 11, 39.3%) and distal pancreatectomy (n = 10, 35.7%). Tumors were located frequently in body and tail regions (n = 18, 64.3%) and the number of patients with malignant criteria was 6 (21.4%). Although the mean age of malignant patients was significantly higher than benign patients (P = 0.046), there was no significant difference between 2 groups in terms of gender, tumor size, capsule invasion, perineural invasion, vascular invasion, and margin status.

CONCLUSION

SPN is a rarely seen tumor with low malignity potential. Surgical resection provides long-term survival rate even in local invasion or metastasis conditions.

TFE3 is a diagnostic marker for solid pseudopapillary neoplasms of the pancreas

Aberrant Wnt signaling is a hallmark of solid pseudopapillary neoplasms (SPNs) of the pancreas. Transcription factor E3 (TFE3) plays a critical role in activation and regulation of the Wnt pathway and is predicted to be a candidate gene implicated in SPN by gene regulatory network analysis. The aim of this study was to evaluate TFE3 as a marker for SPN. Paraffin-embedded tissues of SPN (n = 75) and other primary pancreatic tumors were analyzed, including pancreatic neuroendocrine tumors (n = 17), pancreatic ductal adenocarcinomas (n = 14), pancreatic neuroendocrine carcinomas (n = 4), and acinar cell carcinomas (n = 3). The clinicopathological features were summarized as well. Differentiation of specific pancreatic duct or acinus was not found in any SPN tissue. Morphologic and immunohistochemical results indicated that SPN displays certain characteristics of neuroendocrine cells. Overall, 71 (94.67%) cases of SPN showed nuclear accumulation for TFE3, most of which displayed moderate to intense expression. The TFE3 positive rates in pancreatic neuroendocrine tumor, pancreatic ductal adenocarcinoma, and pancreatic neuroendocrine carcinoma were 23.53%, 14.29%, and 25%, respectively. All 3 cases of acinar cell carcinoma were negative for TFE3. We conclude that SPN may originate from primordial pancreatic cells and is accompanied by some characteristics of neuroendocrine tumors. TFE3, besides β-catenin, can be an additional diagnostic marker of SPN in differential diagnosis.

Diagnosis and treatment of solid-pseudopapillary tumors of the pancreas: A single institution experience with 97 cases

BACKGROUND/OBJECTIVES

We evaluated the diagnoses and surgical management of solid pseudopapillary tumors of the pancreas (SPTP) in a single center setting.

METHODS

Demographic details, clinical presentations, imaging features, surgical strategies, and pathological findings of 97 consecutive patients who underwent surgery for pathologically confirmed SPTP between 2008 and 2016 were analyzed retrospectively.

RESULTS

A total of 97 patients with SPTP accounted for 2.15% of total pancreatic surgeries (N = 4508). The mean age at diagnosis was 31.6 ± 13.92 years (range: 7-83 years), and males:females were 85:12. Chief complaints were abdominal pain or discomfort (n = 50). The mean transverse tumor diameter was 53.2 ± 2.76 mm (range: 14-170 mm). Tumors were localized to the pancreatic head (38.1%; 37/97), neck (12.4%; 12/97), body and tail (49.5%; 48/97). There were no significant differences in age of onset, presenting symptoms, and sites between males and females. A significant difference was found in the maximum diameter of SPTP across different age groups. Partial pancreatectomy was performed for patient with tumor ≥ 5 cm, and enucleation was performed when tumor was smaller than 5 cm. Pancreatic fistula was the main complication. Immunohistochemical markers for endocrine, exocrine and epithelial factors were used for a final diagnosis. During a median follow-up of 54 months (range: 7-121 months), 84 patients were alive without evidence of recurrence, and 13 patients were lost to follow-up.

CONCLUSION

SPTP surgical resection is a safe procedure with low morbidity and mortality, which is also effective even in the presence of invasiveness and metastases. Accurate initial diagnoses and follow up are essential.

Does Computed Tomography Have the Ability to Differentiate Aggressive From Nonaggressive Solid Pseudopapillary Neoplasm?

OBJECTIVE

The aim of the study was to assess the ability of contrast-enhanced computed tomography (CECT) to differentiate aggressive from nonaggressive solid pseudopapillary neoplasms (SPNs).

MATERIALS AND METHODS

Forty treatment-naive patients with pathologically proven pancreatic SPNs were included. Imaging characteristics were determined by consensus of 3 radiologists blinded to histopathologic aggressiveness. All patients underwent 4-phase CECT using a pancreatic protocol. The regions of interest of the tumor and the normal pancreas were documented on all phases. Lymph nodes were considered metastatic if greater than 1.0 cm in short-axis diameter.Fisher exact and Wilcoxon rank-sum tests were used to compare between aggressive and nonaggressive tumors.

RESULTS

No significant difference was noted between imaging covariates, such as internal hemorrhage, calcification, wall thickness perceptibility, vascular invasion, margins, cystic component, and pancreatic and biliary ductal dilation. Tumors with greater than 62.5 Hounsfield units and progressive enhancement during the delayed phase had aggressive characteristics (P = 0.03).

CONCLUSIONS

On delayed phase CECT, pathologically aggressive SPNs may show greater enhancement than nonaggressive SPNs.

Situs inversus totalis with solid pseudopapillary pancreatic tumor: A case report and review of literature

RATIONALE

Situs inversus totalis (SIT) is a rare anatomical variation of the internal organs, and solid pseudopapillary tumor of the pancreas (SPTP) is a rare tissue type of pancreatic tumors, classified as benign or low-grade malignancy. However, to our knowledge, a patient with SIT and SPTP is extremely rare and has never been reported.

PATIENT CONCERNS

We retrospectively analyzed a case of SIT with SPTP in a 45-year-old woman. The main complaints were abdominal pain and sensation of heaviness for 2 weeks. There was tenderness and a mass that could be palpated in the right upper abdomen.

DIAGNOSES

Heart ultrasonography (USG), chest x-ray, computed tomography (CT), and contrast-enhanced computerized tomography (CECT) revealed a mirror-image dextrocardia and inversion of all abdominal viscera and a space-occupying lesion in the pancreas tail. Abdominal computed tomography angiography (CTA) showed no obvious abnormality of artery. The diagnosis of SPTP was finally made by postoperative pathological examination.

INTERVENTIONS

The patient underwent resection of the pancreatic body and tail and splenectomy via laparotomy to completely remove the tumor.

OUTCOMES

The patient was discharged with specific discomfort on postoperative day 7. At the 1.5-year follow-up, she recovered without issue.

LESSONS

Surgical resection remains the only effective treatment of SPTP. SIT with SPTP can be accurately diagnosed by heart USG, chest x-ray, CT, and CECT of the upper abdomen. Abdominal aorta CTA before surgery can decrease the injury risk of blood vessels.

Solid Pseudopapillary Neoplasms of the Pancreas: A Surgical and Genetic Enigma

Solid pseudopapillary neoplasms of the pancreas are rare tumors accounting for 1-2% of pancreatic exocrine neoplasms. This entity was first described by Dr. Frantz in 1959 and was defined by the World Health Organization in 1996 as "solid pseudopapillary tumor." It is most often a benign neoplasm, but 10-15% of the cases are malignant. Over the past decades, the incidence of this tumor is increasing. However, many surgeons are still unfamiliar with this neoplasm and its unique characteristics, which can lead to pitfalls in the diagnosis and treatment. The correct diagnosis of SPNP is of utmost importance since it has a low malignant potential and with the appropriate treatment, patients have a long life expectancy. There are many genetic alterations, involving various signaling pathways that have been associated with SPNP and are very important in diagnosing the tumor. The cornerstone of SPNP treatment includes surgical excision of the tumor, preserving as much pancreatic tissue as possible. We review the information in the literature regarding more organ-preserving techniques and possible clinical features that might indicate a malignant potential, thus demanding a more radical intraoperative excision.

LEF1, TFE3, and AR are putative diagnostic markers of solid pseudopapillary neoplasms

The diagnosis of solid pseudopapillary neoplasms (SPNs) is challenging because some SPNs share many similar morphological and immunohistochemical features with other pancreatic neoplasms. In this study, we investigated potential diagnostic markers of SPN.

Based on the SPN-specific upregulated genes from a previous DNA microarray and proteome study, we selected six immunohistochemical markers [beta-catenin, androgen receptor (AR), lymphoid enhancer-binding factor 1 (LEF1), transcription factor for immunoglobulin heavy-chain enhancer 3 (TFE3), fused in sarcoma (FUS), and WNT inhibitory factor 1 (WIF-1)]. We also evaluated the Ki-67 proliferative index to investigate its associations with prognosis. To validate these markers, we studied 91 SPNs as well as 51 pancreatic ductal carcinomas (PDC) and 48 neuroendocrine tumors (NET) as controls.

We found frequent and diffuse nuclear expressions of β-catenin (98.9%), AR (81.3%), LEF1 (93.4%), TFE3 (74.7%), FUS (84.6%), and cytoplasmic expression of WIF-1 (96.7%) in SPNs. In contrast, PDCs and NETs showed no expression. (P < 0.001). When beta-catenin, LEF1, and TFE3 staining were combined, the sensitivity and specificity were 100% and 91.9%, respectively. Four (4.4%) SPNs showed distant metastasis and these tumors were associated with a relatively high Ki-67 proliferative index (≥ 5%; P = 0.013).

We identified LEF1, TFE3, and AR as putative diagnostic markers of SPN, auxiliary to β-catenin. Incorporated into an immunohistochemical panel, these markers could be beneficial to distinguish SPN from PDC and NET. In addition, we suggest that the Ki-67 proliferative index can be a predictive marker of metastasis in SPNs.

Solid Pseudopapillary Neoplasm of the Pancreas: Clinicopathologic Feature, Risk Factors of Malignancy, and Survival Analysis of 53 Cases from a Single Center

Introduction

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare tumor of low malignant potential. The aim of this study was designed to evaluate the clinicopathologic feature, predictive factors of malignancy, and survival from experience of a single center.

Methods

53 consecutive patients who underwent surgery for a pathologically definitive SPN were retrospectively reviewed.

Results

A total of 53 cases included 7 male cases and 46 female cases with the median age of 35.4 years (14-67). Abdominal pain and mass were the most common clinical presentations. The radiological presentations were consistent with solid and cystic pattern in 18 cases, solid pattern in 25 cases, and cystic pattern in 10 cases. The predominant location of tumor was pancreatic body and tail. The mean size of the tumors was 6.4 cm. Aggressive en bloc resection combined with organ-preserving should be indicated whenever feasible. Follow-up information was available for 48 patients with a median follow-up time of 48 months. The 5-year disease-specific survival was 95.7%. Incomplete capsule was not only the predictive factor of malignancy but also the significant predictor of disease-specific survival.

Conclusion

Incomplete capsule may suggest a malignant SPN and a prognostic indicator of disease-specific survival. We recommend that surgeons consider a more radical resection with an incomplete capsule of tumor.

Differential diagnosis between pancreatic neuroendocrine and solid pseudopapillary neoplasms on endoscopic ultrasound-guided fine-needle aspiration. An immunohistochemical study

Objectives:

To evaluate the role of applying a limited panel of immunohistochemical stains on the cellblock preparation from samples obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in the aim of differentiating solid pseudopapillary neoplasms (SPNs) from neuroendocrine tumors (NETs).

Methods:

We retrospectively retrieved all the EUS-FNAs of the pancreas that have a diagnosis of NET or SPN that were performed at 2 tertiary care hospitals in Riyadh, Kingdom of Saudi Arabia from May 2004 to December 2014. Diff-Quik, Papanicolaou, and Immunohistochemistry stains on cellblock preparations were performed.

Results:

Twenty cases were available (16 pancreatic neuroendocrine tumors (pNETs) and 4 SPNs). The pNETs were immunoreactive for synaptophysin, chromogranin A and CD56 while E-cadherin was diffusely to focally cytoplasmic positive. β-catenin was negative or showed focal cytoplasmic immunoreactivity. In comparison, SPNs were positive for vimentin, CD10, CD-56, focally positive for progesterone receptors and synaptophysin, and revealed nuclear immunostaining for β-catenin. They were negative for chromogranin A and E-cadherin.

Conclusion:

Based on EUS-FNA samples, nuclear immunoreactivity for β-catenin with loss of membranous immunostaining for E-Cadherin can potentially facilitate differentiating SPNs from pNETs.

Solid pseudopapillary neoplasm of the pancreas: Management and long-term outcome

BACKGROUND

Solid pseudopapillary neoplasm (SPN) of pancreas is a rare pancreatic neoplasm with a low metastatic potential. Our aim was to study the clinical-pathological characteristics, and long-term outcome of this tumor.

MATERIALS

Rretrospective single center study of patients operated for SPN of pancreas. Clinical and pathological data were collected.

RESULTS

From 1995 to 2016, 1320 patients underwent pancreatic resection. SPN was confirmed in 32 cases (2.46%), including 29 (90.6%) female and three (9.4%) male, with a mean age of 28.4 ± 12.2 years. SPN was the most common pathology among female patients under age of 40 (72.4%). Abdominal pain was the most frequent presenting symptom (48%), whereas none of the patients presented with jaundice. Mean tumor diameter was 5.9 cm (range, 0.9-14 cm). All patients underwent margin-negative surgical resection. Two patients demonstrated gross malignant features, including liver metastases at presentation (n = 1), and adjacent organ and vascular invasion (n = 1). Microscopic malignant features were present in thirteen patients (40.6%). Recurrence occurred in the retroperitoneal lymph nodes (n = 1, 7 years post resection) and in the liver (n = 2, 1 and 5 years post resection). Mean follow-up was 49.2 months (range, 1-228 months). Five and 10-year disease-free survival was 96.5% and 89.6% respectively.

CONCLUSIONS

SPNs are low-grade tumors with a good prognosis. Margin-negative surgical resection is curative in most patients. However, almost 15% of patients demonstrate malignant features including invasion of adjacent organs or metastatic disease. Patients with malignant disease are still expected to have long survival, and aggressive surgical approach is advocated.

Prevalence, Diagnosis and Management of Pancreatic Cystic Neoplasms: Current Status and Future Directions

Cystic neoplasms of the pancreas are found with increasing prevalence, especially in elderly asymptomatic individuals. Although the overall risk of malignancy is very low, the presence of these pancreatic cysts is associated with a large degree of anxiety and further medical investigation due to concerns about malignancy. This review discusses the different cystic neoplasms of the pancreas and reports diagnostic strategies based on clinical features and imaging data. Surgical and nonsurgical management of the most common cystic neoplasms, based on the recently revised Sendai guidelines, is also discussed, with special reference to intraductal papillary mucinous neoplasm (IPMN; particularly the branch duct variant), which is the lesion most frequently identified incidentally. IPMN pathology, its risk for development into pancreatic ductal adenocarcinoma, the pros and cons of current guidelines for management, and the potential role of endoscopic ultrasound in determining cancer risk are discussed. Finally, surgical treatment, strategies for surveillance of pancreatic cysts, and possible future directions are discussed.

Solid Pseudopapillary Neoplasm of Pancreas; A Case Series and Review Literature

BACKGROUND

Information regarding solid pseudopapillary neoplasm (SPN) of the pancreas is limited in Iran. We aimed to review the clinicocytopathological features and follow-up of patients with SPN of pancreas who were diagnosed in a single center in Iran.

METHODS

Seven patients with SPN of the pancreas were diagnosed during January 2010 to March 2015 at the Digestive Disease Research Institute of Tehran University of Medical Sciences. The patients were reviewed prospectively.

RESULTS

Six out of the 7 patients were female and the mean age of all the patients was 29.4 years ranging from 15 to 61 years. The most common clinical presentation was nonspecific abdominal pain (N=6). The tumors were located mostly in head and neck of the pancreas. SPN was diagnosed in all patients by fine needle aspiration through endosonography (EUS-FNA). All patients underwent surgery. Histological findings of surgical tissues were consistent with EUS-FNA. The postoperative follow-up period of about 14 months was uneventful.

CONCLUSION

SPN of the pancreas is a rare pancreatic tumor which affects primarily young women. EUS-guided FNA could play an important role in preoperative diagnosis of SPN of the pancreas.

Solid Pseudopapillary Tumor of the Pancreas in a 50-Year-Old Man: A Case Report and Review of the Literature

Background: A solid pseudopapillary tumor (SPT) of the pancreas is a rare neoplasm with low malignancy, constituting about 2% of pancreatic tumors, which mainly occurs in young women. Case Presentation: We herein report a case of a small SPT arising from the head of the pancreas in an asymptomatic 50-year-old man. This patient was admitted to our department at Henan Provincial People's Hospital for the evaluation of a pancreatic mass and a pancreatic resection was performed. Histology revealed the lesion to be an SPT of the pancreas, with the characteristic pseudopapilla formation, central degeneration, and capsule formation. The tumor was positive for vimentin, CD10, α1-antichymotrypsin, α1-antitrypsin, β-catenin, neuron-specific enolase, synaptophysin, and progesterone receptor. Conclusion: We diagnosed an SPT in the patient based on these histological findings and immunophenotype.

Extrapancreatic solid pseudopapillary tumors: A clinicopathological analysis of two cases

Solid pseudopapillary tumors (SPTs) are unusual neoplasms that mostly occur in the pancreas, and predominantly affect young women. As a low-grade malignant neoplasm of the exocrine pancreas, they occasionally metastasize, usually to the liver or peritoneum. It has been reported that <1% of SPTs are primary extrapancreatic SPTs. In the present study, we present two rare, but conspicuous extrapancreatic SPTs. Both occurred in young women, and showed good prognoses following surgery. One was a recurrent SPT of the pancreas that metastasized to the ovary, and the other was a distinct primary neoplasm that arose in the retroperitoneal area. The pathological features of the two tumors, including solid and pseudopapillary growth patterns with pale or eosinophilic cytoplasm, were characteristic of SPTs of the pancreas. However, in the case of the metastatic ovarian tumor, focal necrosis and an increased nuclear-to-cytoplasmic ratio were observed. The presence of positive nuclear-cytoplasmic β-catenin, the loss of membranous E-cadherin expression, and a perinuclear punctate CD99 staining pattern on immunohistochemistical analysis, were essential features for diagnosis. The aim of the present study was to compare the morphological and immunohistochemical features of these tumors with those typical of pancreatic SPTs, and to raise awareness that SPTs are able to metastasize to unusual sites, and may also arise as primary tumors outside the pancreas, which may lead to diagnostic dilemmas.

Prognostic role of sex steroid receptors in pancreatic adenocarcinoma

From the available literature, it is unclear what proportion of pancreatic adenocarcinomas express estrogen receptors (ERα, ERβ), progesterone receptors (PR), and androgen receptors (AR), and if any of these markers have prognostic significance. We aimed to assess (1) the expression and (2) the correlation of the aforementioned markers with clinicopathological parameters and prognosis in patients with pancreatic adenocarcinoma. During a five-year period, 60 patients with pancreatic ductal adenocarcinoma underwent surgical resection at a single institution. Immunohistochemical stains of the studied markers were quantified by Image analysis system. ERα expression was positively associated with PR expression. Moreover, ERβ was inversely associated with the presence of metastases, whereas no significant associations implicated AR. As far as the prognostic significance of the studied receptors is concerned, higher ERα expression correlated with poorer survival at the univariate analysis, but the finding dissipated at the multivariate approach. No significant associations with overall survival were noted regarding the other receptors. The role of sex hormone receptors in the survival from pancreatic adenocarcinoma seems rather limited. Further prospective studies assessing those receptors should ideally be designed in order to confirm our results and possibly outline additional correlations between other steroid receptors and features of pancreatic adenocarcinoma.

Solid Pseudopapillary Tumor in a Pregnant Woman: Imaging Findings and Literature Review

A solid pseudopapillary neoplasm is a rare pancreatic tumor accounting for 1-2% of exocrine pancreatic neoplasms. It is usually asymptomatic and discovered incidentally. It is mainly seen in young women between the second and third decades of life. Although it usually has a large size at the time of diagnosis, it is considered to have low malignant potential. Solid pseudopapillary tumors (SPTs) have characteristic magnetic resonance imaging (MRI) features that enable it to be differentiated from other more common pancreatic tumors. Here, we report the case of a 34-year-old pregnant woman who was admitted to The Royal Hospital, Oman, with a large mass in her pancreas, which was incidentally discovered during abdominal ultrasonography. The mass was investigated further with MRI. The MRI revealed a well-defined mass related to the tail and body of the pancreas with solid and cystic components. It had a heterogeneous texture with fluid levels of different signal intensities due to the presence of blood of different ages. The cystic-solid appearance of an encapsulated lesion with characteristic signal intensity on MRI suggested the possibility of a SPT. Postoperative histopathology results confirmed the diagnosis of a SPT. In this case report, we highlight the MRI features of a SPT and discuss how to differentiate it from other cystic pancreatic tumors to increase the awareness of clinicians to this rare pancreatic tumor.

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.

Solid Pseudopapillary Neoplasm of the Pancreas: Analysis of Seven Cases

Background

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

Methods

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

Results

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

Conclusions

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

Solid Pseudopapillary Neoplasms of the Pancreas: a 19-Year Multicenter Experience in China

AIM

The aim of this study was to determine the clinicopathological features, surgical management, and prognosis of solid pseudopapillary neoplasms (SPNs) of the pancreas.

METHODS

This study conducted a retrospective analysis of 97 patients who underwent surgery for a pathologically confirmed SPN in five hospitals between January 1996 and December 2014.

RESULTS

The 97 cases included 93 female and 4 male patients, and the average age was 31.2 years. The tumor was located in the body or tail (70.1%), the head (20.6%), and the neck (9.3%). All patients underwent surgical exploration, including distal pancreatectomy (63.9%), pancreaticoduodenectomy (20.6%) (partial portal vein or superior mesenteric vein resection and artificial vascular graft reconstruction performed in 4.1% of the patients), central pancreatectomy (10.3%), enucleation (5.2%), and liver resection (1.0%). 16.5% of the patients had malignant tumors. The positive rate of Ki-67 was 66.7% in patients diagnosed with a malignant neoplasm and was comparable to 8.4% of the patients diagnosed to have a benign neoplasm (p < 0.001). After a median follow-up of 70.1 months, three patients had recurrence and one patient died of liver metastasis.

CONCLUSIONS

SPN is a rare neoplasm with low malignant potential. Surgical resection is warranted even in the presence of local invasion or metastases as patients demonstrate excellent long-term survival. Positive immunoreactivity for Ki-67 may predict the malignant potential and poor outcome of SPNs.

Retrospective analysis of short term outcomes after spleen-preserving distal pancreatectomy for sodid pseudopapillary tumours

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.

Predicting recurrence of pancreatic solid pseudopapillary tumors after surgical resection: a multicenter analysis in Korea

BACKGROUND

Solid pseudopapillary tumors (SPTs) of the pancreas are still considered a surgical enigma. Many clinical research trials have failed to identify prognostic factors that predict the malignant behavior of SPTs.

MATERIALS AND METHODS

This work was a retrospective multicenter study that included a total of 17 medical institutions. Data from 351 patients who underwent surgical resection from January 1990 to December 2008 were retrospectively collected using standardized case report forms requesting clinicopathologic features.

RESULTS

Thirty-four patients (9.7%) were male, and 317 (90.3%) were female, with a mean age of 36.8 ± 12.4 years. Recently, minimally invasive (P < 0.001) and parenchyma or function-preserving limited surgeries (P = 0.016) have been more frequently applied for the treatment of pancreatic SPTs. Ninety-eight patients (27.9%) had microscopic malignant features. Only 9 patients (2.6%) experienced tumor recurrence after the initial pancreatic SPT resection. Multivariate analysis showed that a tumor size larger than 8 cm [Exp (β) = 7.385, P = 0.018], microscopic malignant features [Exp (β) = 10.009, P = 0.011], and stage IV [Exp (β) = 42.003, P = 0.002] were significant prognostic factors for tumor recurrence. When combined with stage IV, the microscopic malignant features and 2010 World Health Organization definition of solid pseudopapillary carcinoma more successfully differentiated future recurrence risk groups (P < 0.001).

CONCLUSIONS

More specific pathologic descriptions need to be employed in pathologic report forms to provide proper information to predict SPT recurrence after resection. Future studies emphasizing the standardized pathologic evaluation of pancreatic SPTs may unveil the enigmatic nature of pancreatic SPTs.

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.

Diagnosis and molecular aspects of solid-pseudopapillary neoplasms of the pancreas

Solid-pseudopapillary neoplasm of the pancreas (SPN) is an uncommon low-grade malignant neoplasm occurring mostly in young women. In addition to its distinctive pathological appearance of pseudopapillae with poorly cohesive neoplastic cells, rare variants exist raising the differential diagnosis especially with neuroendocrine neoplasms. The overall prognosis for patients with SPNs is excellent after surgical resection. Nevertheless, 10% of cases may have malignant behavior characterized by tumor recurrence and/or metastasis. Despite numerous studies, the histogenesis of this neoplasm remains unclear. Distinctive molecular alterations such as the presence of CTNNB1 mutations are observed in nearly all cases, while mutations classically observed in ductal adenocarcinoma, such as KRAS, TP53, and SMAD4, are not observed in SPNs, reinforcing its distinct nature compared to all other pancreatic neoplasms. Recent transcriptional studies have shown that activation of the Wnt/beta-catenin pathway in these tumors is associated with the upregulation of genes belonging to Notch, Hedgehog, and androgen receptor signaling pathways.

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 management and long-term follow-up of solid pseudopapillary tumor of pancreas: a large series from a single institution

OBJECTIVE

We summarized the diagnosis, surgical strategies, and long-term follow-up outcomes in our large series of solid pseudopapillary tumors (SPTs) of pancreas.

METHODS

In this retrospective analysis, we collected data pertaining to pancreatic SPTs diagnosed in 115 patients between July 2003 and February 2013.We analyzed the demographic characteristics, clinical presentations, operative strategies, perioperative details, and follow-up outcomes.

RESULTS

Abdominal pain was the most frequent symptom (40.0%). The most frequent location of SPT was pancreatic tail (36.5%). We performed 33 cases of pancreaticoduodenectomy, 15 cases of middle pancreatectomy, 19 cases of distal pancreatectomy with spleen preservation, 28 cases of distal pancreatectomy with splenectomy, and 18 cases of enucleation. Two patients suffered tumor recurrence and required a second resection of the recurrent tumor.

CONCLUSIONS

Complete resection of the tumor is associated with good survival, even in patients with vessel involvement or metastases. In patients with tumor recurrence, a second resection resulted in long-term survival.

Solid pseudopapillary neoplasm of the pancreas: clinicopathologic and survival analyses of 64 cases from a single institution

Although solid pseudopapillary neoplasms (SPNs) are considered tumors of low malignant potential, patients may present with aggressive disease (ie, liver metastasis/invasion into adjacent organs) and, rarely, die from disease. Although the clinicopathologic features associated with aggressive SPNs have been reported, important prognostic factors of survival remain unclear. We systematically reviewed 64 cases of SPN resected at our institution for tumor size, extent of invasion, margin status, presence of lymphovascular, muscular vessel, and perineural invasion, and lymph node and distant metastases. Clinicopathologic characteristics were correlated with the presence of metastasis/recurrence and disease-specific survival. Five (8%) patients presented with stage IV disease. During follow-up, 5 (13%) of 39 patients with stage I-II disease had recurrences. Patients with metastatic/recurrent SPNs had significantly larger tumor size (P<0.001) and more frequent tumor invasion into muscular vessels (P=0.02). In a median follow-up of 76 months, only 2 died of disease (1 who presented with extensive peritoneal tumor involvement who died 2.5 mo after surgery, and 1 unusual case who presented with multiple liver metastasis and peritoneal seeding who died 19 mo after surgery), and 5 were alive with disease. The 10-year disease-specific survival rate was 96%. Muscular vessel invasion (P=0.001), tumor (T) stage by European Neuroendocrine Tumors Society (ENETS) classification (P<0.001), ENETS stage grouping (P<0.001), and stage grouping by the American Joint Committee on Cancer (AJCC stage, P<0.001) were important predictors of disease-specific survival in patients with SPN. Our study highlights the importance of pathologic evaluation in risk assessment in patients with SPNs.

Solid pseudopapillary neoplasm of the pancreas: a case report with review of the diagnostic dilemmas and tumor behavior

Solid pseudopapillary neoplasm of the pancreas is a rare tumor of the pancreas often detected initially on imaging. Of uncertain histogenesis, it has a low-grade malignant potential with excellent post-surgical curative rates and rare metastasis. Despite advances in imaging, pseudocysts and other cystic neoplasms feature in the differential diagnosis. Pathological and/or cytological evaluation remains the gold standard in reaching a definitive diagnosis. On morphology alone, other primary pancreatic tumors and metastatic tumors pose a diagnostic challenge. Recent advances in immunohistochemical characterization have made the histopathologic diagnosis more specific and, in turn, shed light on the likely histogenesis of this rare tumor. We report a case of solid pseudopapillary neoplasm of the pancreas that was suspected on radiology and diagnosed intraoperatively on imprint cytology guiding definitive surgery. The diagnostic dilemmas are reviewed.