Solid pseudopapillary tumors of the pancreas: review of 718 patients reported in English literature

Frantz's tumor: is mutilating surgery always justified in young patients?

BACKGROUND

Solid pseudopapillary tumor (Frantz's tumor) of the pancreas is a rare lesion. It is of low-grade malignancy but can cause extensive local invasion. The aim of this study was to assess the outcome of Frantz's tumors after incomplete resection.

METHODS

We contacted all authors who published case reports describing incomplete resection of Frantz's tumor between 1985 and 2008 to request follow-up information.

RESULTS

Follow-up information was obtained for 11 out 18 patients who underwent incomplete resection. Estimated median survival rate was 5.7 years (69.5 months).

CONCLUSION

Since Frantz's tumor typically develops mainly in children and young women, a 5.7 year survival rate is unacceptable. Thus complete resection of locally invasive solid-pseudopapillary tumor of the pancreas is always justified, even at the price of difficult, mutilating surgery.

Solid-pseudopapillary neoplasm: a pancreatic enigma

Solid-pseudopapillary neoplasm of the pancreas is a relatively uncommon tumor. It typically affects young women, has nonspecific clinical and radiologic manifestations, and can be readily diagnosed by ultrasound-guided fine-needle aspiration and histopathologic evaluation. Histologic features characteristically show loosely cohesive, relatively uniform polygonal cells surrounding delicate capillary-sized blood vessels. Other features include cytoplasmic vacuolization, finely stippled chromatin, nuclear grooving, eosinophilic hyaline globules, and degenerative changes. Almost all solid-pseudopapillary neoplasms harbor mutations in the beta-catenin gene. They stain with beta-catenin, CD10, and focally with neuroendocrine markers. Although previously considered benign, this tumor is currently considered a low-grade malignant epithelial neoplasm with low metastatic rate and high overall survival. Most patients are cured by complete surgical excision. Despite the characterization of the morphologic and molecular features of this enigmatic neoplasm, more work is needed to uncover its cell of origin and true histogenesis.

An unusual presentation of pancreatic pseudocyst mimicking cystic neoplasm of the pancreas: a case report

In spite of their rarity, cystic neoplasms of the pancreas are characterized by existing or potential malignancy that cannot be ignored during decisive process with regard to the choice of treatment. Diagnostic difficulties in the differentiation of pancreatic pseudocyst and cystic pancreatic neoplasm can lead to misdiagnosis and inappropriate treatment, since clinical symptoms, preoperative imaging tests and even endoscopic retrograde cholangiopancreatography are often not sufficient to establish the correct diagnosis. We present a case of pancreatic cyst with no typical features of pseudocyst in the medical interview, treated by Child's subtotal pancreatectomy by reason of the high risk of neoplasia suggested by radiological and endoscopic examinations.

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.

Differentiation of benign and malignant solid pseudopapillary neoplasms of the pancreas

OBJECTIVE

The aim of this study was to investigate differential imaging features between benign and malignant solid pseudopapillary neoplasms (SPN) of the pancreas on computed tomographic and magnetic resonance imagings.

METHODS

Between January 2001 and January 2007, we identified 30 patients with confirmed SPN by surgery. The computed tomographic and magnetic resonance images were reviewed by 3 radiologists in consensus. Each tumor was analyzed for the following categories: location of tumor, tumor margin, proportion of solid component, morphology of capsule, growth pattern, calcification, and presence of upstream pancreatic ductal dilatation.

RESULTS

Benign SPN usually had oval/round or smoothly lobulated margins, and malignant SPN more commonly had focal lobulated margins (P = 0.027). Presence of complete encapsulation was more frequently seen in benign SPN, whereas focal discontinuity of capsule was more commonly seen in malignant SPN (P = 0.005). There was no statistical difference between benign and malignant tumors in other imaging findings.

CONCLUSIONS

A focal lobulated margin and a focal discontinuity of the capsule may suggest malignant SPN, whereas a round or smoothly lobulated margin and a complete encapsulation were more commonly seen in benign SPN.

[A case of atypical Solid-pseudopapillary tumor of the pancreas]

Solid-psudopapillary tumor is an uncommon pancreatic neoplasm of low malignant potential that most frequently affect young woman. Solid-psudopapillary tumor are histologically, clinically, and prognostically quite distinct from the more common ductal adenocarcinoma. Recently, we experienced a 36-year-old male who was suspected to have extrapancreatic tumor based on atypical radiologic imaging study, young age, and male sex, and finally diagnosed as solid-psudopapillary tumor on immunohistochemical stain examination. We report this case with review of the relevant literatures.

Is laparoscopic management suitable for solid pseudo-papillary tumors of the pancreas?

PURPOSE

Solid pseudo-papillary tumors (SPT) are rare pancreatic neoplasms of low-malignant potential occurring mainly in young women. The purpose of this report is to describe our experience with laparoscopic management of these tumors with 4-year follow-up.

METHODS

Three children with SPT were admitted to two hospitals in Paris, France, between February 2000 and December 2006. Diagnosis or treatment was carried out using laparoscopic techniques (biopsy and resection in one case and biopsy only in two). Long-term follow-up data were collected.

RESULTS

All three patients presented recurrences within 3 years after resection, i.e., disseminated peritoneal recurrence in two patients and local recurrence in one. The two patients with peritoneal recurrences were treated by surgical resection and chemotherapy. The patient with local recurrence could not be treated due to contraindicating local factors. All three patients were alive at the time of this writing.

CONCLUSION

This is the first report describing long-term follow-up after laparoscopic management of SPT. All three patients developed recurrences. These poor results contrast sharply with the low risk of local or disseminated recurrence after open laparotomy without chemotherapy that has been considered as the treatment of choice up to now. Recurrences after laparoscopic management may have been due to diffusion of tumor cells caused by gas insufflation especially during biopsy. Laparoscopic biopsy should not be performed in patients presenting SPT.

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

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.

Expression pattern of claudins 5 and 7 distinguishes solid-pseudopapillary from pancreatoblastoma, acinar cell and endocrine tumors of the pancreas

Solid-pseudopapillary tumor (SPT) of the pancreas is characterized by a discohesive appearance of the neoplastic cells. This has been linked to the displacement of E-cadherin and beta-catenin from their normal membrane location, which prevents adherens junctions to form. The nuclear localization of beta-catenin is also a feature of SPT that helps in differential diagnosis. This latter includes pancreatic endocrine tumor (PET) as SPT may show neuroendocrine differentiation, and pancreatic acinar cell carcinoma (ACC) and pancreatoblastoma (PB) that may often show nuclear beta-catenin staining. However, the role of additional cell-cell adhesion systems remains to be elucidated in SPT, particularly that of claudins that are essential components of tight junctions showing modulated expression in diverse tumor types. We studied 20 SPT, 20 nonfunctioning PET, 7 ACC, 2 PB, and their matched normal pancreas for the immunohistochemical expression of claudin family members 1, 2, 3, 4, 5, and 7, beta-catenin and E-cadherin. All SPT showed intense membrane claudin 5 and cytoplasmic claudin 2 staining, lack of claudins 3 and 4, and positive cytoplasmic claudins 1 and 7 in few cases. Conversely, PET, ACC, and PB showed strong membrane expression of claudin 7 and lack of claudin 5, whereas claudins 1, 2, 3, and 4 showed variable expression among samples. All SPT showed nuclear beta-catenin and lack of E-cadherin membrane staining, whereas PET, ACC, and PB only showed nuclear beta-catenin in 1, 2, and 2 cases, respectively. SPT shows a peculiar claudin expression profile and the highly specific pattern of claudins 5 and 7 differentiates SPT from PET, ACC, and PB.

Case report: Adult phenotype of Mulvihill-Smith syndrome

Mulvihill-Smith syndrome (MSS) is characterized by premature aging, multiple pigmented nevi, decreased facial subcutaneous fat, microcephaly, short stature, mental retardation and recurrent infections, however the adult phenotype of MSS has yet to be delineated. We report a 28-year-old woman with Mulvihill-Smith syndrome, who had a solid pseudopapillary cystic tumor of her pancreas at age 17 years. Her distinctive sleep pattern includes severe insomnia with disappearance of sleep spindles and K-complexes, persisting muscle tone, and loss of slow wave sleep. The clinical and neurophysiological studies are compatible with agrypnia excitata, a sleep disorder attributable to a dysfunction of the thalamo-limbic system. Brain magnetic resonance imaging and single photon emission computed tomography revealed structural and functional deficits in the dorsomedial region of the thalamus and indicated that an alteration in the thalamo-limbic system may underlie the sleep disturbances in MSS. Furthermore, the rapid and severe decline in acquired cognitive function showed the distinct cognitive impairments resembling dementia, including intellectual deficits, memory disorder and executive dysfunction. We posit that an early onset tumor, sleep disorder and cognitive decline are adult manifestations of Mulvihill-Smith syndrome.

Solid pseudopapillary tumor in a pancreatic rest of the jejunum

Solid pseudopapillary tumors of the pancreas (SPTP) are very rare, and an SPTP arising in a pancreatic rest has been reported only 4 times previously and never in association with the jejunum. We report this unusual case of a 16 year old girl who presented with 4 days of intermittent, crampy abdominal pain and was found to have an SPTP arising in a pancreatic rest of the jejunum.

[The solid pseudopapillary tumor of pancreas: two cases and literature review]

Solid pseudopapillary tumor (SPT) of the pancreas is a rare exocrine pancreatic tumor behaving in a low-grade fashion, with limited local invasion risk and a rare metastatic evolution. We report SPT in two young females, revealed by abdominal pain and an epigastric mass. The diagnosis of a cystic tumor was based on abdominal ultrasound and CT data in the first case and on MRI in the second. A distal pancreatectomy and splenectomy were successfully performed in the first case and a central pancreatectomy in the second. Histological study confirmed the diagnosis of SPT of the pancreas.

Living donor liver transplantation for unresectable liver metastases from solid pseudo-papillary tumor of the pancreas: a case report

Solid pseudo-papillary tumors (SPT) are rare primary tumors of the pancreas that primarily affect young women. They are of borderline malignancy, and, unlike other pancreatic malignancies, the prognosis after resection is quite good. However, metastatic disease does occur; the liver is the most common site of tumor dissemination. Herein we have reported a case of a 20-year-old woman who presented with multiple, bilateral liver metastases at 3 years after distal pancreatectomy for SPT of the body and tail of the pancreas. The patient underwent living donor liver transplantation (LDLT) and is alive and disease-free at 24 months after surgery. In this report, we discuss the treatment of liver metastases from SPT, with an emphasis on the possible role of orthotopic liver transplantation (OLT).

Imaging features of solid pseudopapillary tumor of the pancreas on multi-detector row computed tomography

AIM: To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant potential.

METHODS: A total of 24 consecutive cases with surgically and pathologically confirmed SPTs of the pancreas underwent preoperative abdominal MDCT studies in our hospital. All axial CT images, CT angiographic images, and coronally and sagittally reformed images were obtained. The images were retrospectively reviewed at interactive picture archiving and communication system workstations.

RESULTS: Of the 24 cases of SPTs, 11 cases (45.8%) occurred in the pancreatic head and seven (29.1%) in the tail. Eighteen were pathologically diagnosed as benign and six as malignant. MDCT diagnosis of SPTs was well correlated with the surgical and pathological results (Kappa = 0.6, P < 0.05). The size of SPTs ranged from 3 to 15 cm (mean, 5.8 cm). When the size of the tumor was greater than 6 cm (including 6 cm), the possibilities of vascular (8 vs 1) and capsular invasion (9 vs 0) increased significantly (P < 0.05). Two pathologically benign cases with vascular invasion and disrupted capsule on MDCT presented with local recurrence and hepatic metastases during follow-up about 1 year after the resection of the primary tumors.

CONCLUSION: Vascular and capsular invasion with superimposed spread into the adjacent pancreatic parenchyma and nearby structures in SPTs of the pancreas can be accurately revealed by MDCT preoperatively. These imaging findings are predictive of the malignant potential associated with the aggressive behavior of the tumor, even in the pathologically benign cases.

Xanthogranulomatous inflammation of the peripancreatic region mimicking pancreatic cystic neoplasm

Xanthogranulomatous inflammation (XGI) is histopathologically characterized by a marked proliferative fibrosis, parenchymal destruction, and infiltration of foamy histiocytes intermixed with other inflammatory cells. Herein, we report a case of a 73-year-old man without symptoms who was initially diagnosed with a pancreatic cystic tumor but later with XGI in the peripancreatic region. Although XGI has been reported to occur in various organs or tissues, such as the gallbladder, kidney, bone, stomach, colon, appendix, lymph nodes, and soft tissues, XGI involving the pancreas or its surrounding tissues is extremely rare. When a pancreatic cystic lesion does not have typical clinicoradiological features of common pancreatic cystic neoplasms, this pathologic condition should be considered in the differential diagnosis.

Update on the molecular pathogenesis of pancreatic tumors other than common ductal adenocarcinoma

PURPOSE

Although ductal adenocarcinoma is the most common and well known pancreatic tumor type, other distinct epithelial neoplasms affecting the pancreas that show different symptoms, biological behaviors and outcomes are becoming more frequently recognized and documented. Pancreatic epithelial tumors may be separated into ductal and nonductal neoplasms. The former group includes pancreatic ductal adenocarcinoma, intraductal papillary-mucinous tumor, mucinous cystic tumor and serous cystic tumor. The latter group includes pancreatic endocrine tumor, pancreatic acinar cell carcinoma, pancreatoblastoma and solid-pseudopapillary tumor. The aim of this review is to summarize recently acquired knowledge regarding the molecular characterization of these uncommon pancreatic epithelial neoplasms.

RECENT FINDINGS

Molecular studies of uncommon pancreatic epithelial tumors suggest that the different morphological entities are associated with distinct molecular profiles, highlighting the involvement of different molecular pathways leading to the development of each subtype of pancreatic neoplasm.

CONCLUSION

The correct classification of rare pancreatic epithelial tumors and the identification of their characteristic molecular aspects is the fundamental starting point in identifying novel diagnostic molecular tools and new targets for innovative therapeutic strategies.

Clinical experiences of solid pseudopapillary tumors of the pancreas in China

AIMS

To discuss the clinical experiences of solid pseudopapillary tumors (SPTs) of the pancreas by summarizing clinical information of patients with this disease in China.

METHODS

Chinese literature concerning SPTs of the pancreas published between January 1996 and October 2006 were retrospectively reviewed and analyzed.

RESULTS

A total of 390 cases had been reported, among which 47 were men, with a female to male ratio of 7.30:1. Mean age of the patients was 25.3 years old, more than 50 per cent were between 10 and 24 years. The mean diameter of the tumor was 8.4 cm (range, 2 cm-25 cm). There was no significant difference in patient age and tumor size between male and female. Major clinical presentations included abdominal pain or discomfort, and palpable abdominal masses, however, nearly one third of all patients were asymptomatic. The rate of pre-operative misdiagnosis was rather high. Those who tested positive to metastases or invasions, 14.4% of the patients were diagnosed as malignant SPTs. Sex, age, symptoms, tumor size and tumor markers were not significant clinical factors to predict SPTs with malignant potential. Surgical procedures mainly included pancreatoduodenectomy, distal pancreatectomy and local resection. Three patients developed local recurrence, and one patient developed hepatic metastasis, all within four years after tumor resection. Five patients with malignant SPTs died due to tumor progression within 25 months after surgery.

CONCLUSIONS

Surgical resection is the most effective means for curing this rare tumor. Despite metastasis, a good satisfactory effect could be achieved by surgical debulking. At least 4-yearly follow-up is mandatory for all patients undergoing surgical resection.

[Solid pseudopapillary pancreas tumors--often neglected]

Solid pseudopapillary tumors of the pancreas (SPTP) are rare tumors of the pancreas with low malignancy potential and a very good prognostic outcome after surgery. They typically occur in young women or adolescents and consist of solid, cystic and cystic-hemorrhagic components.Imaging findings in these tumors are characteristic and include a fibrotic capsule with a clear delineation and exhibit solid and cystic-hemorrhagic signal and density characteristics. Calcifications may be present in the periphery of the tumor. The tumor capsule shows contrast enhancement, the solid components in the periphery enhance in the early phase and gradually and inhomogeneously in late phases. MRI is superior to CT and other imaging modalities for characterization of SPTP. Awareness and knowledge of this tumor entity with an excellent prognosis is crucial to guide the patient towards effective, predominantly organ-sparing surgical treatment.

Clinical features and surgical treatment for solid pseudo-papillary tumor of the pancreas

AIM: To summarize the clinical features of and surgical treatment for solid pseudo-papillary tumor of the pancreas (SPTP).

METHODS: Eleven cases of SPTP diagnosed between January 2001 and April 2008 in our hospital were retrospectively analyzed. The main indicators included clinical features, B ultrasound and CT scan characteristics, pathological results and follow-up, etc.

RESULTS: Two cases of tumors were located in the pancreatic head, one tumor was in the neck of pancreas and 8 tumors were in the body and tail of pancreas. There were no specific clinical manifestations except 2 cases with acute abdominal pain. Solid and solid-cystic masses of low echo were found in pancreas under ultrasonic examinations. CT scan showed masses of low density in pancreas, while irregular enhancement appeared in the circumference of all tumors in enhanced CT scan sequences. Tumor markers in patients' serum were all negative except one case. Pancreaticoduodenectomy was performed on 3 cases. Simple resection of tumor was performed on 3 cases. Five patients underwent distal pancreatectomy and spleen resection. Ten patients were followed up with the average time of 23.7 months. No evidence of relapses and metastasis in these cases was found.

CONCLUSION: Solid pseudo-papillary tumor of pancreas is one of rare pancreatic neoplasm with low malignant potential, affecting primarily young women. Patients with SPTP have a favorable outcome after surgical treatment.

Large, clear cytoplasmic vacuolation: an under-recognized cytologic clue to distinguish solid pseudopapillary neoplasms of the pancreas from pancreatic endocrine neoplasms on fine-needle aspiration

BACKGROUND

Solid pseudopapillary neoplasm (SPN) and pancreatic endocrine neoplasm (PEN) are uncommon neoplasms that demonstrate characteristic cytologic features. It is also known that both these tumors may share similar morphologic changes. These features not uncommonly pose significant diagnostic challenge for unsuspecting cytopathologists. In the current study, the authors report that recognition of clear cytoplasmic vacuoles in endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) samples from SPN serves as a useful clue that can distinguish this tumor from PEN.

METHODS

The cytologic features from 5 SPN and 20 PEN cases were evaluated. Both Diff-Quik and Papanicolaou stains from these cases were examined. A Fisher exact test of probability was performed to determine differences in the individual cytologic features noted in these 2 tumor types.

RESULTS

The results demonstrated that pseudopapillary groups (P = .004); metachromatic matrix material (P = .004); nuclear membrane irregularity (P = .004); and large, clear cytoplasmic vacuoles (P = .001) are noted significantly more frequently in SPN. The authors also demonstrated that large, clear cytoplasmic vacuoles can serve as a powerful cytologic clue for the suspicion of SPN over PEN when there is a paucity of papillary groups within the smears. Large, clear cytoplasmic vacuoles, however, were noted only in Diff-Quik-stained smears, but not in Papanicolaou-;stained smears.

CONCLUSIONS

The results of the current study highlight that large, clear cytoplasmic vacuoles can serve as a critical clue with which to distinguish SPN from PEN in diagnostically challenging cases.

A spindle cell predominant pancreatic solid-pseudopapillary tumor

A hitherto unrecognized variant of solid-pseudopapillary tumor (SPT) of the pancreas is reported. The tumor presented in the pancreatic tail of a 44-year-old female patient. It was a well-defined, solid nodule measuring 25 mm in diameter, with homogenous tan gray cut surface. Histologically, the neoplasm was mostly composed of sheets of spindle cells. No cellular atypia and mitosis was identified. The periphery of the tumor showed typical feature of SPT. Immunohistochemically, the tumor cells were positive for vimentin, CD10, CD56, beta-catenin, and alpha1-antichymotrypsin, but negative for cytokeratin, chromogranin, synaptophysin and S-100 protein. Ultrastructurally, the tumor showed a few acinar spaces with microvilli between tumor cells. This case is peculiar in that the tumor did not show gross cystic change and predominantly consists of spindle shaped tumor cells, so may cause difficult diagnostic problem.

Hematemesis, a very rare presentation of solid pseudo-papillary tumors of the pancreas: a case report

Introduction

Solid pseudo-papillary tumors of the pancreas are rare and typically present in young female patients. They are slowly growing masses that may attain large size, and are of low malignant potential. Surgical resection is usually curative.

Case presentation

A 71-year-old woman presented to the emergency department with an episode of hematemesis but was otherwise hemodynamically stable. Emergency gastroscopy revealed a bleeding mass projecting to the duodenum. Fluid, blood and electrolyte resuscitation followed. Computed tomography revealed a small mass in the head of the pancreas. A Whipple operation was performed. Pathology revealed a solid pseudo-papillary tumor. The postoperative course of the patient was uneventful and no recurrence was present a year after the operation.

Conclusion

In our case, the most noteworthy observations concern the small size of the tumor, the age of the patient and the presenting symptom. However, pancreaticoduodenectomy in a 71-year-old woman is a major effort and should only be undertaken by centers and surgeons experienced in complex hepatobiliary surgery. Furthermore, the unique nature of this case reminds every clinician that each patient has to be considered separately and with extreme caution.

Current diagnosis and management of unusual pancreatic tumors

BACKGROUND

The finding of a solid or cystic mass in the pancreas is becoming more common secondary to the increasing use of cross-sectional imaging and the improved sensitivity of such studies for the detection of pancreatic abnormalities. Because of the aggressive natural history of pancreatic cancer, this has caused concern that all pancreatic abnormalities may be cancer as well as confusion over proper diagnostic and treatment algorithms. This review provides an overview of the natural history, diagnostic considerations, and treatment recommendations for the less common tumors of the pancreas which can be misinterpreted as pancreatic cancer including: solid pseudopapillary tumors (SPT), acinar cell carcinoma (ACC), lymphoplasmacytic sclerosing pancreatitis (LPSP), primary pancreatic lymphoma (PPL), and metastatic renal cell carcinoma to the pancreas.

DATA SOURCES

A Medline search was conducted to identify studies investigating the clinicopathologic features, molecular genetics, pathogenesis, diagnosis, and treatment of SPT, ACC, LPSP, PPL, and pancreatic metastases.

CONCLUSIONS

It is often possible to obtain an accurate pretreatment diagnosis for these unusual pancreatic tumors and to successfully differentiate them from the more common pancreatic malignancies.

[Solid pseudopapillary neoplasm of the pancreas]

Solid pseudopapillary neoplasms (SPN) of the pancreas are rare tumours with low malignant potential, usually affecting young women. Due to its relatively low incidence, there are no international guidelines published on diagnosis or treatment. The aims of our study were to summarize our clinical experience of SPN in a Hungarian Surgical Centre and to discuss the relevant international literature. The clinical data of four patients treated between 2004 and 2007 in the Petz Aladár County Teaching Hospital (Gyôr, Hungary) were analyzed retrospectively. All patients were women with age of 17-49 years. In all cases SPN was diagnosed preoperatively on the basis of CT-findings and the diagnosis was confirmed by postoperative histology. After an organ-preserving radical resection of the tumour, all patients have remained disease free with an acceptable quality of life so far. Our data suggest that CT-scan is adequate to establish the preoperative diagnosis of SPN. Surgical resection should be carried out with the required radicality, but organ preservation is advised in order to provide a relatively good quality of life.

Aggressive behaviour of solid-pseudopapillary tumor of the pancreas in adults: A case report and review of the literature

Solid-pseudopapillary tumor (SPT) is a rare neoplasm of the pancreas that usually occurs in young females. It is generally considered a low-grade malignant tumor that can remain asymptomatic for several years. The occurrence of infiltrating varieties of SPT is around 10%-15%. Between 1986 and 2006, 282 cystic tumors of the pancreas were observed. Among them a SPT was diagnosed in 8 patients (2.8%) with only one infiltrating variety. This was diagnosed in a 49-year-old female 13 years after the sonographic evidence of a small pancreatic cystic lesion interpreted as a pseudocyst. The tumor invaded a long segment of the portal-mesenteric vein confluence, and was removed with a total pancreatectomy, resection of the portal vein and reconstruction with the internal jugular vein. Histological examination confirmed the R-0 resection of the primary SPT, although a vascular invasion was demonstrated. The postoperative course was uneventful, but 32 mo after surgery the patient experienced diffuse liver metastases. Chemotherapy with different drugs was started. The patient is alive and symptom-free, with stable disease, 75 mo after surgery. Twenty-five patients with invasion of the portal vein and/or of mesenteric vessels were retrieved from the literature, 16 recent patients with tumor relapse after potentially curative resection were also retrieved. The best treatment remains a radical resection whenever possible, even in locally advanced or metastatic disease. The role of chemotherapy, and/or radiotherapy, is still to be defined.

Benign pancreatic tumors

The goal of this article is to describe the different types of benign pancreatic neoplasms, methods to distinguish between them, and treatment options. Pancreatic adenocarcinoma is associated with specific neoplastic lesions that are similar in radiographic appearance to some benign lesions. The correct differentiation of these malignant and premalignant lesions from their benign counterpart is paramount to their proper management.

Solid pseudopapillary tumor of the pancreas: a review of salient clinical and pathologic features

Solid pseudopapillary tumor (SPT) of the pancreas is a rare tumor of uncertain histogenesis characterized, as the name suggests, by a cystic and solid pattern of growth with formation of pseudopapillae. Accounting for only a small percentage of pancreatic neoplasms, SPT occurs primarily in young women, although cases in older patients and men have been reported. The tumor is thought to have low-grade malignant potential, as the majority of the cases are cured by simple but complete surgical resection. Knowledge of the unique morphologic and demographic characteristics of this neoplasm is essential for accurate diagnosis. Herein, we review the clinical and pathologic features, which can help separate SPTs from other primary pancreatic tumors.

Liver transplantation for multiple liver metastases from solid pseudopapillary tumor of the pancreas

Solid pseudopapillary tumor (SPT) of the pancreas usually shows a benign clinical course. However, sometimes, distant metastasis may occur. Even in such case, the prognosis is good only if metastatic lesions are resected completely. We report the case of a 14-year-old girl with SPT of the pancreas and unresectable synchronous liver metastasis who underwent successful living donor liver transplantation. For 2 years, she has been disease free. This is the first report on transplantation to relieve liver metastasis of SPT.

Solid pseudopapillary neoplasm of the pancreas: distinct patterns of onset, diagnosis, and prognosis for male versus female patients

BACKGROUND

Solid pseudopapillary neoplasm of the pancreas is a distinctive pancreatic neoplasm with low metastatic potential. This study examines clinical differences and prognosis between male and female patients.

METHODS

The medical records of 34 consecutive patients with pancreatic solid pseudopapillary neoplasms between 1990 and 2006 were reviewed. Whenever feasible, organ-preserving operation was performed. Statistical analysis was performed using chi-square and Student t test.

RESULTS

There were 27 women (79%) and seven men (21%) with median age of 23 years. Mean diameter of the tumor was 7 cm. Tumor size tended to be smaller in patients treated in more recent years. Conservative surgery was possible in 11 patients including spleen-preserving distal pancreatectomy in 3, central pancreatectomy in 5, and enucleation in 3 patients. Median hospital stay was 11 days, morbidity rate was 62%, including 17 patients with grade A pancreatic fistula, and there was no operative mortality. Mean follow-up time was 84 months. Tumor recurred in 2 patients (6%). Overall late morbidity rate was 12%. At the time of diagnosis, age was (x +/- SD) higher among male patients (25 +/- 2 years vs 37 +/- 7 years; P <.05) with no difference in tumor size. The neoplasms were more aggressive in male patients; therefore, conservative surgery was less likely. There was no correlation between tumor aggressiveness and age of the patient or size of tumor.

CONCLUSION

This is the first single center study to demonstrate that solid pseudopapillary neoplasms in male patients have distinct patterns of onset and aggressiveness when compared with female patients. Although valid prognostic criteria are still lacking, it appears that male patients may be best treated by more radical operation and should be observed more closely during follow-up.

Clinical potential of an antitumor drug sensitivity test and diffusion-weighted MRI in a patient with a recurrent solid pseudopapillary tumor of the pancreas

A solid pseudopapillary tumor (SPT) of the pancreas is a rare type of pancreatic neoplasm found predominantly in young women. SPTs typically behave as though benign; however, in some cases they also have malignant potential. We encountered a rare case of a recurrent SPT that developed 4 years after the initial surgery in an elderly male patient. Abdominal computed tomography (CT) revealed that the 61-year-old patient had four intra-abdominal masses, suggesting a recurrence of SPT. The patient had a history of distal pancreatectomy due to SPT in the pancreatic tail 4 years previously. These tumors showed positive signals on diffusion-weighted magnetic resonance imaging (MRI), and were treated successfully by aggressive surgical resection. Microscopic diagnosis was compatible with recurrent tumors of SPT. A chemosensitivity test, the collagen gel droplet-embedded culture drug sensitivity test (CD-DST), showed that the resected tumors were sensitive to several antitumor drugs. We suggest that the CD-DST may be used to indicate promising antitumor agents for treating SPTs with malignant tendencies. In addition, a diffusion-weighted MRI can be useful for accurately visualizing SPTs of the pancreas.

Cystic neoplasms of the exocrine pancreas

The increasing use of radiological imaging has led to greater detection of small and asymptomatic cystic lesions of the pancreas. Most are resectable, but not all are neoplastic. This review provides an update on the histopathology, immunohistochemistry, molecular biology, pathogenesis and management of cystic neoplasms of the exocrine pancreas. These include the serous, the mucinous cystic, the intraductal papillary mucinous and the solid pseudopapillary neoplasms. Recently reported variants are described and very rare cystic variants of other pancreatic epithelial and mesenchymal neoplasms are briefly mentioned.

Solid pseudopapillary neoplasms of the pancreas: an updated experience

INTRODUCTION

The aim of this study is to report an update of the surgical experience at a single institution with these unusual tumors.

METHODS

Sixteen consecutive patients who underwent surgery for a pathologically confirmed solid pseudopapillary neoplasm (SPPN) were retrospectively reviewed.

RESULTS

Fifteen of the patients were female and the median age at diagnosis was 30 years (range, 14-53 years). Abdominal and back pain were the most common presenting symptoms. The tumors appeared on cross-sectional imaging as solid and cystic (n = 14) or cystic (n = 2) masses. The median tumor size was 9.5 cm (range, 5.0-24.0 cm). All 16 patients had curative resections including 3 pancreaticoduodenectomies and 13 distal pancreatectomies. Three patients required extended resections including pancreaticoduodenectomy with portal vein resection, distal pancreatectomy with tranverse colectomy, and distal pancreactomy with omentectomy. Two of the resections were R1 whereas 14 were R0. All patients were alive and disease-free at a median follow-up of 43 months (range, 3-186 months).

CONCLUSION

SPPNs should be considered in young women presenting with a large solid-cystic pancreatic mass. Aggressive en bloc resection should always be attempted including resection of concomitant metastases as patients demonstrate excellent long-term survival even in the presence of distant spread.

Presentation and management of pancreatic cystic neoplasms

Pancreatic cystic neoplasms are less frequent than other pancreatic tumors, but because of the wide availability and improvement of modern imaging methods, these neoplasms are being recognized with increasing frequency and it is often possible to be differentiated preoperatively not only from other cystic pancreatic disorders but also from one another. Most patients have no symptoms while clinical signs are not really useful in the clinical work up, and when they are present, they never help us to identify the type of pathology. Treatment differs with the diagnosis. Serous cystic neoplasms are uniformly benign and usually do not mandate resection unless this lesion is symptomatic. In contrast, mucinous cystic neoplasms and intraductal papillary mucinous neoplasms have a premalignant or malignant tendency, and therefore should be managed aggressively by pancreatic resection; in the absence of invasive disease, prognosis is excellent after appropriate surgery, but the presence of invasive malignancy signifies a poor prognosis. Solid pseudopapillary neoplasms have nonaggressive behavior and their management is related to the extension of the disease. The purpose of this article is to review the types of pancreatic cystic neoplasms, their diagnosis, indications for surgical treatment, and outcome.

Loss of cell-adhesion molecule complexes in solid pseudopapillary tumor of pancreas

Solid pseudopapillary tumor of pancreas (SPT) is a rare neoplasm that occurs most often in young females with the two distinct features, the 'solid-cystic' gross appearance, and the 'solid-pseudopapillary' microscopic pattern. It has been reported that almost all SPT tumors contain a mutation in the beta-catenin gene; however, the histogenetic origin of this tumor remains largely a mystery. E-cadherin is a cell adhesion molecule that links to catenins to form cell adhesion junctions, which is associated with the cytoskeleton formation. In this study, we examined the expression of E-cadherin and beta-catenin from SPT in an attempt to determine the molecular basis for the unusual morphology of this tumor. Nine cases of SPT were retrieved from Surgical Pathologic Archives of three institutions, including one male and eight females. H&E slides of each case were reviewed to confirm the diagnosis. The beta-catenin gene was sequenced in one case. E-cadherin and beta-catenin immunostains, were performed on all nine cases. Sequencing analysis on one case showed a point mutation of the beta-catenin gene, confirming previous findings that almost all SPT tumors contain mutation in the beta-catenin gene. Immunostains showed that, in both solid and pseudopapillary areas, all the tumor cells lost expression of E-cadherin, and beta-catenin nuclear expression was observed in all cases. Our findings suggest that loss of cytoplasmic beta-catenin protein in the cell adhesion complex due to beta-catenin gene mutation, results in instability of the complex, loss of E-cadherin in cell membrane, and eventually dissociation of the tumor cells to form the pseudopapillary pattern.

Solid-pseudopapillary tumors of the pancreas: case report and literature review

Solid pseudopapillary tumors (SPT) of the pancreas are rare neoplasms of low malignant potential that mostly affect young women. These tumors are of unclear pathogenesis, are slow growing, and can become considerably large before causing symptoms. Complete resection is curative in most cases. This is the case of a 39-year-old African-American woman undergoing evaluation for Roux-en-Y gastric bypass, who was found to have a pancreatic mass. Image-guided biopsy revealed SPT. The patient underwent complete excision of the tumor and had an open Roux-en-Y gastric bypass performed concurrently. The patient had an uneventful postoperative course. A review of the literature is presented.

Pancreatic tumors in children: radiologic-pathologic correlation

Pancreatic neoplasms are rare in children and have a different histologic spectrum and prognosis than those in adults. In general, these tumors are well demarcated with expansile rather than infiltrating growth patterns. They may be quite large at diagnosis, and central cystic necrosis is common. They infrequently cause biliary duct obstruction. The imaging appearance of each neoplasm reflects its pathologic features. Pancreatoblastoma is the most common pancreatic neoplasm in young children. At imaging, pancreatoblastomas are heterogeneous and often multilocular with hyperechoic and enhancing septa. Solid-pseudopapillary tumor occurs in adolescent girls. It is heterogeneous in internal architecture, with a mixture of solid and cystic hemorrhagic and necrotic elements. This tumor is distinguished by its fibrous capsule and hemorrhagic nature, which are best shown at magnetic resonance imaging as a dark rim on T1- or T2-weighted images and hyper-intense foci on T1-weighted images, respectively. Islet cell tumors in children are insulinomas or gastrinomas. These tumors manifest early due to hormonal syndromes and are distinguished by their small size, homogeneous appearance, and intense enhancement with intravenous contrast material. All pancreatic neoplasms in children are capable of producing metastases, usually to the liver and lymph nodes; however, on the whole, these tumors have a better clinical outcome than most pancreatic tumors in adults. Knowledge of the differential diagnosis of pancreatic masses in children and their relatively good prognosis may promote correct preoperative diagnosis and appropriate treatment.

Positive immunohistochemical staining of KIT in solid-pseudopapillary neoplasms of the pancreas is not associated with KIT/PDGFRA mutations

Solid-pseudopapillary neoplasms of the pancreas are uncommon neoplasms of low malignant potential and of uncertain histogenesis. A small percentage of patients develop metastatic disease and some succumb to disease. The management of patients with metastatic disease or unresectable tumor, and patients who are just not good surgical candidates is problematic. Novel therapy targets are needed. Successful treatment of metastatic and unresectable gastrointestinal stromal tumors with KIT kinase inhibitor, imatinib mesylate (Gleevec), makes it intriguing to look at the status of KIT in solid-pseudopapillary neoplasms of the pancreas. In this study, we investigated KIT expression in 50 solid-pseudopapillary neoplasms by immunohistochemical staining. Of the 50 (50%) solid-pseudopapillary neoplasms, 25 showed diffuse expression (in >50% neoplastic cells) of KIT and additional five (10%) cases showed focal staining (in 10-50% neoplastic cells). Expression of KIT was not associated with tumor behavior and prognosis. A subset of 11 cases showing diffuse KIT expression detected by immunohistochemical staining were further evaluated for the presence of activating mutations in KIT exons 9, 11, 13 and 17, and PDGFRA exons 12 and 18 using PCR amplification followed by direct sequencing. However, no KIT or PDGFRA mutations were identified in any of these 11 cases tested, suggesting that the overexpression of KIT is probably not due to activating mutations in KIT or PDGFRA. The exact mechanism of KIT overexpression in solid-pseudopapillary neoplasms remains to be elucidated. One possible mechanism is gene dose effect (increased copies of KIT gene). Experience in gastrointestinal stromal tumors and other tumors have shown that mutation-mediated activation of KIT or PDGFRA is a prerequisite for clinical response with imatinib mesylate. Thus, lack of mutations in KIT or PDGFRA in solid-pseudopapillary neoplasms suggests that imatinib mesylate is less likely to be effective in the treatment for patients with metastatic disease or unresectable tumor, and patients who are just not good surgical candidates.