Solid pseudopapillary carcinoma of the pancreas: differentiation from benign solid pseudopapillary tumour using CT and MRI

Development of a nomogram for predicting the high-risk groups of solid-pseudopapillary neoplasms of the pancreas

Background

Solid pseudopapillary neoplasms (SPNs) of the pancreas are indolent rare tumors with malignant potential. The risk factors associated with the malignant behavior of SPNs are still unclear.

Methods

A retrospective analysis of patients with SPNs who underwent surgical treatment in the First Hospital of Jilin University from January 2010 to January 2022 was conducted. The clinical baseline data, pathology, imaging, and laboratory indicators of the patients were analyzed by univariate and multivariate logistic regression to identify the independent risk factors associated with the high-risk groups, and a predictive model was established in the form of a nomogram.

Results

In multivariate analysis, clinical symptoms (P < 0.001), unclear tumor margins (P = 0.001), incomplete tumor capsules (P = 0.005), maximum tumor diameters ≥ 7.2 cm (P = 0.003), and prognostic nutritional index values < 47.45 (P = 0.007) were independent risk factor for SPNs with high-risk groups. A nomogram model was successfully established to predict high-risk groups of SPNs. The area under the receiver operating characteristic curve was 0.856. The calibration prediction curve was in good agreement with the standard curve.

Conclusion

The nomogram model based on clinical symptoms, inflammatory markers, and imaging features had a high application value in the preoperative prediction of the high-risk groups of SPNs. A novel nomogram of the affiliated hospital of Jilin University-SPNs risk model was proposed for routine application to guide the patient counseling in clinical practice.

Cinematic rendering of solid pseudopapillary tumors: Augmenting diagnostics of an increasingly encountered tumor

Pancreatic solid pseudopapillary tumors (SPTs) are a rare subset of pancreatic neoplasms, accounting for under 2 % of exocrine pancreatic tumors. The incidence of SPTs has shown a significant increase in the past two decades, attributed to heightened cross-sectional imaging utilization. These tumors often present with nonspecific clinical symptoms, making imaging a crucial tool in their detection and diagnosis. Cinematic rendering (CR) is an advanced 3D post-processing technique that generates highly photorealistic realistic images by accurately modeling the interaction of light within the imaged volume. This allows improved visualization of anatomic structures which holds potential to improve diagnostics. In this manuscript we present the first description of CR appearances of SPTs in the reported literature. Through showcasing a range of cases, we highlight the potential of CR in illustrating the diverse imaging characteristics of these unique neoplasms.

Rare Solid Pancreatic Lesions on Cross-Sectional Imaging

Several solid lesions can be found within the pancreas mainly arising from the exocrine and endocrine pancreatic tissue. Among all pancreatic malignancies, the most common subtype is pancreatic ductal adenocarcinoma (PDAC), to a point that pancreatic cancer and PDAC are used interchangeably. But, in addition to PDAC, and to the other most common and well-known solid lesions, either related to benign conditions, such as pancreatitis, or not so benign, such as pancreatic neuroendocrine neoplasms (pNENs), there are solid pancreatic lesions considered rare due to their low incidence. These lesions may originate from a cell line with a differentiation other than exocrine/endocrine, such as from the nerve sheath as for pancreatic schwannoma or from mesenchymal cells as for solitary fibrous tumour. These rare solid pancreatic lesions may show a behaviour that ranges in a benign to highly aggressive malignant spectrum. This review includes cases of an intrapancreatic accessory spleen, pancreatic tuberculosis, solid serous cystadenoma, solid pseudopapillary tumour, pancreatic schwannoma, purely intraductal neuroendocrine tumour, pancreatic fibrous solitary tumour, acinar cell carcinoma, undifferentiated carcinoma with osteoclastic-like giant cells, adenosquamous carcinoma, colloid carcinoma of the pancreas, primary leiomyosarcoma of the pancreas, primary and secondary pancreatic lymphoma and metastases within the pancreas. Therefore, it is important to determine the correct diagnosis to ensure optimal patient management. Because of their rarity, their existence is less well known and, when depicted, in most cases incidentally, the correct diagnosis remains challenging. However, there are some typical imaging features present on cross-sectional imaging modalities that, taken into account with the clinical and biological context, contribute substantially to achieve the correct diagnosis.

The Role of MRI in the Diagnosis of Solid Pseudopapillary Neoplasm of the Pancreas and Its Mimickers: A Case-Based Review with Emphasis on Differential Diagnosis

Solid pseudopapillary neoplasm (SPN) is rare pancreatic tumor occurring most commonly in young females. The typical imaging appearance of SPN is of well-defined, encapsulated, and large heterogeneous tumors, consisting of solid and cystic components due to various degrees of intralesional hemorrhage and necrosis. However, atypical imaging presentation in the form of small solid tumors or uniformly cystic lesions might also be seen, which can be explained by specific pathological characteristics. Other imaging features such as a round shape, the absence of main pancreatic duct dilatation, and slow growth, in combination with vague symptoms, favor the diagnosis of SPNs. Nevertheless, the radiological findings of SPN might overlap with other solid and cystic pancreatic neoplasms, such as neuroendocrine tumors, serous and mucinous neoplasms, and even small pancreatic adenocarcinomas. In addition, a few benign non-tumorous conditions including walled-of-necrosis, and intrapancreatic accessory spleen may also pose diagnostic dilemmas simulating SPNs on imaging studies. The aim of this manuscript is to provide a comprehensive overview of the typical and atypical imaging features of SPNs and to describe useful tips for differential diagnosis with its potential mimickers.

Preoperative prediction of invasive behavior of pancreatic solid pseudopapillary neoplasm by MRI-based multiparametric radiomics models

OBJECTIVE

A log-combined model was developed to predict the invasive behavior of pancreatic solid pseudopapillary neoplasm (pSPN) based on clinical and radiomic features extracted from multiparametric magnetic resonance imaging (MRI).

MATERIALS AND METHODS

A total of 111 patients with pathologically confirmed pSPN who underwent preoperative plain and contrast-enhanced MRI were included, and divided into an invasive group (n = 34) and non-invasive group (n = 77). Clinical features and laboratory data related to pSPN invasive behavior were analyzed. Regions of interest were delineated based on T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and contrast-enhanced T1WI (CE-T1WI) to extract radiomic features. Correlation analysis was performed for these features, followed by L1_based feature selection (C = 0.15). A logistic regression algorithm was used to construct models based on each of the four sequences and a log-combined model was used to integrate the sequences. A receiver operating characteristic (ROC) curve was plotted to evaluate the model performance, and the Brier score was used to assess the overall accuracy of the model predictions.

RESULTS

The area under the ROC curve was 0.68, 0.73, 0.71, and 0.49 for Log-T1WI, Log-T2WI, Log-DWI, and Log-CE models, respectively, and 0.81 for the log-combined model. The accuracy, precision, sensitivity, and specificity of the log-combined model were 0.77, 0.88, 0.75, and 0.78, respectively. The best performance was obtained with the log-combined model with a Brier score of 0.18. Tumor location was identified as a significant clinical feature in comparison between the two groups (p < 0.05), and invasive pSPN was more frequent in the tail of the pancreas.

CONCLUSION

The log-combined model based on multiparametric MRI and clinical features can be used as a non-invasive diagnostic tool for preoperative prediction of pSPN invasive behavior and to facilitate the development of individualized treatment strategies and monitoring management plans.

Large Solid Pseudopapillary Tumor Pancreas with Extensive Splenoportal Thrombosis and Malignant Transformation—A Rare Entity

Solid pseudopapillary tumor (SPT) is an uncommon low-grade malignant cystic exocrine neoplasm of the pancreas that typically affects young women. The tumor has an excellent prognosis after surgical resection. Vascular involvement is usually not seen at presentation. Local recurrence and metastasis are also rare. Herein, we present a case of large, locally advanced SPT in a young female with splenoportal extension and malignant transformation.

Solid pseudopapillary neoplasm of the pancreas in a young male with main pancreatic duct dilatation: A case report

BACKGROUND

Solid pseudopapillary neoplasms (SPNs) are rare tumors of the pancreas. Typically, they occur in young females, often have characteristic imaging features, such as cystic components and calcification, and have few effects on the pancreatic duct.

CASE SUMMARY

A 31-year-old man was admitted to our hospital with the chief complaint of epigastric pain. There was only mild tenderness in his upper abdomen, and blood tests showed only a slight increase in alkaline phosphatase. Contrast-enhanced computed tomography showed a 40-mm-diameter, hypovascular mass in the head of the pancreas, and the main pancreatic duct upstream of the mass was severely dilated. Magnetic resonance imaging showed low intensity on T1-weighted images, with high intensity on T2-weighted image in some parts. Pancreatic ductal adenocarcinoma was the primary differential diagnosis. Portal vein infiltration could not be ruled out, so this case was a candidate for neoadjuvant chemotherapy. Subsequently, endoscopic ultrasound-guided fine needle aspiration was performed, and pathological evaluation and immunostaining suggested a diagnosis of SPN. Thus, pancreatoduodenectomy was performed. One year after the operation, the patient is alive with no recurrence.

CONCLUSION

Main pancreatic duct dilatation is usually a finding of suspected pancreatic cancer. However, pancreatic duct dilatation can occur in SPN depending on the location and growth speed. Therefore, SPN should be considered in the differential diagnosis of tumors with pancreatic duct dilatation, and pathological evaluation by endoscopic ultrasound-guided fine needle aspiration should be actively performed.

Pseudopapillary solid tumour of the pancreas in paediatric age: description of a case report and review of the literature

Pseudopapillary solid tumour of the pancreas is a rare neoplasm that mainly affects young women in the second and third decade of life and less frequently children; originates from the exocrine component of the pancreas; and is characterized by slow growth, low potential for malignancy, and excellent prognosis following complete surgical resection. The tumour often presents as an asymptomatic abdominal mass that is accidentally detected during radiological investigations performed for other reasons. In this article, we report the clinical case of a 10-year-old girl who came to our observation for pain in the left hypochondrium, which had arisen for a week following a trauma; the imaging methods revealed a voluminous expansive pancreatic formation in the abdomen; on histological examination, the mass was a solid pseudopapillary tumour. Furthermore, we present a review of the literature aimed at highlighting the salient features of this neoplasm in paediatric age.

Solid pseudopapillary neoplasm-diagnostic approach and post-surgical follow up: Three case reports and review of literature

BACKGROUND

Solid pseudopapillary neoplasm (SPN) is a rare tumor that was first described by Frantz in 1959. Although this tumor is benign, some may have malignant potential that can be predicted based on demographics, imaging characteristics, and pathologic evaluation. This case series presents 3 SPN cases with discussion on gender differences, preoperative predictors of malignancy, and a suggested algorithm for diagnostic approach as well as post-surgical follow up.

CASE SUMMARY

Three adult patients in a tertiary hospital found to have SPN, one elderly male and two young females. Each of the cases presented with abdominal pain and were discovered incidentally. Two cases underwent endoscopic ultrasound with fine needle aspiration and biopsy to assess tumor markers and immuno-histochemical staining (which were consistent with SPN before undergoing surgery), and one case underwent surgery directly after imaging. The average tumor size was 5 cm. Diagnosis was confirmed by histology. Two patients had post-surgical complications requiring intervention.

CONCLUSION

Demographic and imaging characteristics can be sufficient to establish diagnosis for SPN, while malignant cases require pre-operative evaluation with endoscopic ultrasound fine needle aspiration/fine needle biopsy.

Clinical manifestations and multi-slice computed tomography characteristics of solid pseudopapillary neoplasms of the pancreas between males and females

Background

Solid-pseudo papillary neoplasms of pancreas (SPNP) are rare in men and are often misdiagnosed. This study aimed to analyze the clinical and multi-slice computer tomography (MSCT) features of patients with SPNP, and examine the differences between males and females.

Methods

In this retrospective cohort study, the clinical and imaging data of 29 patients with histolopathologically confirmed SPNP (seven males and 22 females) that underwent radical resection, and underwent preoperative MSCT at the First People’s Hospital of Lianyungang between August 2010 and December 2018 were collected. All MSCT images were reviewed by two radiologists; disagreements were ruled by a third one.

Results

The median age of the 29 patients with SPNP was 30 (range, 12–70) years. The male patients were older than the female patients [median, 56 (28–66) vs. 29 (12–70), P = 0.012]. The median tumor size was 3.9 (range, 2.0–6.4) cm in the male SPNP patients, which was significantly lower than the 7.0 (range, 4.6–14.6) cm in the female patients (P < 0.001). The calcification rate of the SPNP was significantly higher in male than in female patients (P = 0.013). The percentage of solid tumor was higher in males than in females (P = 0.036). Capsule, bleeding, and enhancement in the arterial and venous phases were not significantly different between the male and female patients (all P > 0.05).

Conclusion

The imaging features of male SPNP are distinct from those of female patients. In males with pancreatic lesions, MSCT generally shows relatively small lesions with higher percentages of solid components and calcification, with typical enhancement suggesting SPNP.

Differentiation of aggressive from non-aggressive pancreatic solid pseudopapillary neoplasms using computed tomography

PURPOSES

Microscopic aggressive behaviors may be related with the prognosis of solid pseudopapillary neoplasms (SPNs). In this study, we investigate computed tomography (CT) features and differential diagnosis of aggressive and non-aggressive SPNs in pancreas.

MATERIALS AND METHODS

122 patients with pathologically proven SPNs in pancreas were included. Patients' age, tumor site, texture, shape, margins, exophytic growth, capsule, calcification, hemorrhage, pancreatic duct dilatation or pancreatic parenchyma atrophy, peripancreatic infiltration or metastases, vascular encasement, and enhancement pattern were assessed. The diagnostic accuracy was analyzed by using the receiver operating characteristic curve (ROC).

RESULTS

There were 30 aggressive SPNs and 92 non-aggressive SPNs. Aggressive SPNs showed significantly higher frequencies of an ill-defined margin, patient age > 40.5 years, and tumor size < 42.1 mm, but lower frequencies of complete capsule, hemorrhage compared with non-aggressive SPNs (p < 0.05). Lack of complete capsule and age > 40.5 years were independent risk factors of aggressive SPNs (odd ratio 7.08 and 3.1, respectively). When we applied the two predictors in the logistic regression model, the area under the curve (AUC) was 0.77 with sensitivity of 86.7% and specificity of 55.4%.

CONCLUSION

Size less than 42.1 mm, lack of complete capsule, ill-defined, and absent bleeding are useful CT imaging features for predicating aggressive SPNs. Patient age > 40.5 years and lack of complete capsule showed acceptable diagnostic performance for discriminating aggressive from non-aggressive SPNs.

Management of solid pseudopapillary neoplasms of pancreas: A single center experience of 243 consecutive patients

BACKGROUND

Solid pseudopapillary neoplasm of the pancreas (SPN) is a rare neoplasm, which mainly affects young women. The aim of this study was to investigate the clinicopathological features and surgical management of SPNs in our institution.

METHODS

Patients who underwent surgery for a pathologically confirmed SPN in our institution between January 2008 and October 2018 were collected. Their clinical characteristics and survival associations were analyzed.

RESULTS

In total, 243 pathologically confirmed patients were analyzed in this study, including 181(74.5%)females and 62(25.5%) males. The mean age was 35.3 years old (range: 12-64 years old) with average tumor size of 4.83 cm (range: 0.8-16 cm). 239 patients underwent complete surgical resection. After median follow-up of 46 months (range: 10-118 months), four patients died due to tumor progression. All the other people were absent of local recurrence or distant metastasis.

CONCLUSIONS

SPN is a latent malignant tumor with excellent prognosis. Surgical resection is recommended even in the presence of liver metastasis. If possible, function-preserving surgery is advocated. High Ki67 index may predict the malignant potential and poor prognosis of SPNs.

Calcified peripancreatic lymph nodes in pancreatic and hepatic tuberculosis mimicking pancreatic malignancy: A case report and review of literature

RATIONALE

Tuberculosis remains a serious menace to the health of people. Isolated hepatic tuberculosis is rare and pancreatic tuberculosis is extremely rare. The preoperative diagnosis of pancreatic tuberculosis remains a great challenge.

PATIENT CONCERNS

A 58-year-old Asian woman was referred to our hospital for evaluation of low back pain for 4 years and abdominal pain for 1 month.

DIAGNOSES

Computed tomography (CT) of the abdomen showed a hypodense mass in the pancreatic head and neck with abundant calcifications, a hypodense lesion in the liver without calcification, peripancreatic lymphadenopathy, calcifications in some lymph nodes. CT-guided fine needle aspiration biopsy of the hepatic lesion was carried out and the cytological examination revealed hepatic tuberculosis.

INTERVENTIONS

The patient was treated with antituberculous therapy for 1 year.

OUTCOMES

Low back pain and abdominal pain disappeared 3 months after initial treatment and after 2 year of follow-up, the patient was asymptomatic.

LESSONS

Our data hint that calcifications in both pancreatic lesions and peripancreatic lymph nodes may suggest pancreatic tuberculosis rather than pancreatic malignancy.

Radiological Workup of Cystic Neoplasms of the Pancreas

Pancreatic cystic lesions are being detected with increasing frequency because of increased use and improved quality of cross-sectional imaging techniques. Pancreatic cystic lesions encompass non-neoplastic lesions (such as pancreatitis-related collections) and neoplastic tumors. Common cystic pancreatic neoplasms include serous cystadenomas, mucinous cystic neoplasms, intraductal papillary mucinous neoplasms, and solid pseudopapillary tumors. These cystic pancreatic neoplasms may have typical morphology, but at times show overlapping imaging features on cross-sectional examinations. This article reviews the classical and atypical imaging features of commonly encountered cystic pancreatic neoplasms and presents the limitations of current cross-sectional imaging techniques in accurately classifying pancreatic cystic lesions.

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.

Endoscopic Ultrasound Imaging for Diagnosing and Treating Pancreatic Cysts

Cystic pancreatic lesions are increasingly diagnosed owing to the abundant use of cross-sectional imaging. Given their malignant potential, true pancreatic cysts should be considered for resection or periodic follow-up. Cystic lesions of the pancreas (CLPs) require further evaluation and management. Therefore, it is important to establish a solid diagnosis at the time of detection. Endoscopic ultrasound examination is the imaging modality of choice. Fine needle aspiration provides fluid for cytologic, biochemical, and molecular assays to classify lesions and predict biological behavior. This review provides an overview of the diagnosis and management of various types of commonly encountered true CLPs.

Solid Pseudopapillary Neoplasm of the Pancreas: A Rare Entity With Unique Features

Solid pseudopapillary neoplasm of the pancreas is a rare entity with low malignant potential and excellent overall prognosis. It has nonspecific clinical presentations such as abdominal pain and nausea, with vague radiologic features. Histologic features of this neoplasm are usually specific. The tumor shows minimally cohesive, uniform, monotonous cells lining delicate capillary-sized blood vessels, described as pseudopapillary architecture. Other features including hyaline globules, cytoplasmic vacuoles, and nuclear grooving are frequently present. Use of a select panel of immunostains always helps pathologists to differentiate this tumor from other circumscribed tumors of the pancreas. Recently, β-catenin, CD10, and E-cadherin have been shown to be very important in the diagnosis of solid pseudopapillary neoplasm. Nuclear staining of tumor cells by β-catenin and membranous presentation of CD10 is seen in almost 100% of cases. Tumor cells can be partially positive for synaptophysin and chromogranin. This tumor has a low malignant potential, and definite treatment is surgical resection.

Clinicopathologic Review of 31 Cases of Solid Pseudopapillary Pancreatic Tumors: Can We Use the Scoring System of Microscopic Features for Suggesting Clinically Malignant Potential?

A solid pseudopapillary tumor (SPT) is a pancreatic neoplasm of low malignant potential. The potentially malignant pathologic features of SPTs were regarded as angioinvasion, perineural invasion, deep invasion of the surrounding acinar tissue, and nuclear pleomorphism. We retrospectively reviewed 31 cases of SPTs (25 female and 6 male patients, with an average age of 35 ± 14 years). The mean follow-up period was 132.0 ± 55.9 months. To evaluate the clinical impact of above pathological parameters, we analyzed their correlation with actually observed clinical malignancy. In three cases, the SPTs were clearly clinically malignant: one patient had recurrences three times, one showed lymph node metastases, and one deep soft tissue invasion around the gastroduodenal artery. Tumor infiltration to the peripancreatic soft tissue was observed in 17 cases (54.8%). The pathologic features considered suggestive of malignant potential were angioinvasion (25.8%), perineural invasion (6.5%), presence of mitosis in 10 high-power fields (16.1%), and moderate nuclear pleomorphism (19.4%). The presence of at least three of these features was not correlated with clinically confirmed malignant behavior (P = 0.570). Microscopic pathologic features of SPTs cannot be reliably associated with aggressive clinical behavior. Moreover, the absence of these microscopic features cannot exclude clinical malignancy.

Two-photon excited fluorescence imaging of the pancreatic solid pseudopapillary tumor without hematoxylin and eosin stains

Solid pseudopapillary tumor (SPT) of the pancreas is an epithelial tumor with low-grade malignant potential and present more common in females. At present, the gold standard for accurate diagnosis of pancreatic tumor was mostly depending on the pathological and/or cytological evaluation. In this work, TPEF microscopy was applied to obtain the images of human normal pancreas and SPT of the pancreas without hematoxylin and eosin (H&E) staining, for the purpose of identifying the organization structural, cell morphological, and cytoplasm changing, which were then compared to their corresponding H&E stained histopathological results. Our results showed that high-resolution TPEF imaging of the pancreatic SPT can clearly distinguish the pathological features from normal pancreas in unstained histological sections, and the results are consistent with the histological results. Moreover, we measured the nuclear-cytoplasmic ratios of the pancreatic SPT and normal pancreas to characterize their difference in the cytomorphological feature. It indicated that this technique can achieve the consistent information of pathological diagnosis, and has the potential to substantially improve the optical diagnosis and treatment of the pancreatic SPT without H&E staining in the future. SCANNING 38:245-250, 2016. © 2015 Wiley Periodicals, Inc.

Surgical treatment of solid pseudopapillary neoplasms of the pancreas and risk factors for malignancy

BACKGROUND

The aim of this study was to identify clinical predictors of malignancy and surgical strategies for pancreatic solid pseudopapillary neoplasm (SPN) by analysis of surgical outcomes at a single institution.

METHODS

All patients who underwent surgery for SPN between 1995 and 2010 were identified. Histopathology slides of all patients were reviewed by a specialized pathologist and the neoplasms were classified according to the criteria of the World Health Organization 2010.

RESULTS

Of the 106 patients identified, 85 (80·2 per cent) were female, and the median age was 36 (range 10-65) years. Median tumour size was 4·5 (range 1·0-15·0) cm. Some 17 patients (16·0 per cent) were classified as having a high-grade malignant SPN. Tumour size of at least 5 cm was associated with high-grade malignant potential (P = 0·022). Although lymph nodes were removed from 40 patients (37·7 per cent), there were no nodal metastases. A total of five patients underwent en bloc resection of adjacent structures, including two with portal vein involvement. After a median follow-up of 56·9 months, two patients with high-grade malignant SPN had evidence of tumour recurrence in the lymph nodes and liver.

CONCLUSION

SPN with a diameter of 5 cm or more is associated with a high-grade malignant phenotype. Complete surgical removal is associated with low recurrence rates.

Solid-pseudopapillary tumor of the pancreas: MR imaging findings in 21 patients

PURPOSE

Solid-pseudopapillary tumor (SPT) of the pancreas is a rare, low-grade malignancy, which mostly occurs in adolescent and young adult females. The goal of this study was to retrospectively analyze the magnetic resonance (MR) imaging presentation of SPT of the pancreas.

METHODS

We retrospectively reviewed the preoperative MR imaging examinations and the medical, surgical and histopathological records of 21 patients who underwent surgery for SPT of the pancreas. MR imaging included T1-weighted, T2-weighted, and gadolinium chelate-enhanced MR imaging. In addition, 10 patients had diffusion-weighted (DW) MR imaging. MR examinations were retrospectively reviewed for location, size, morphological features and signal intensity of the tumors.

RESULTS

Nineteen women and 2 men (median age, 23 years; range, 14-59) were included. Seven patients (7/21; 33%) presented with abdominal symptoms. The median largest tumor diameter was 53mm (range, 32-141 mm). SPTs were located in the pancreatic head, body, and tail in 9 (9/21; 43%), 5 (5/21; 24%) and 7 (7/21, 33%) patients, respectively. All patients (21/21; 100%) had a single SPT. SPTs were more frequently oval (12/21; 57%), predominantly solid (12/21; 57%), fully encapsulated (16/21; 76%), larger than 30 mm (21/21; 100%), hypointense on T1-weighted MR images (21/21, 100%), hyperintense on T2-weighted MR images (21/21; 100%) and with an enhancing capsule after gadolinium-chelate administration (21/21; 100%).

CONCLUSIONS

There is trend of appearance for SPT of the pancreas on MR imaging but that variations may be observed in a number of cases. SPT uniformly presents as a single, well-demarcated and encapsulated pancreatic mass.

Multidetector CT imaging features of solid pseudopapillary tumours of the pancreas in male patients: distinctive imaging features with female patients

OBJECTIVE

To describe multidetector CT imaging features of solid pseudopapillary tumours (SPTs) in male patients and to compare these imaging features with those found in female patients.

METHODS

The institutional review board approved this retrospective study. We included the CT images of 72 patients (M:F = 12:60; mean age, 35.0 years) diagnosed with SPT by histology. CT images were reviewed on the following: location of the tumour, maximal diameter, shape, margin and the fraction of the tumour composition. Statistical differences in CT imaging features were analysed.

RESULTS

Male patients with SPTs were significantly older than female patients (42.4 years vs 33.4 years, p = 0.0408) and the mean size of the SPTs in male patients was larger (6.3 cm vs 4.6 cm, p = 0.0413) than that of SPTs in female patients. Lobulated shape of the SPTs was most frequent in male patients, whereas oval shape was most frequent in female patients (p = 0.0133). SPTs in male patients tended to have a solid component (p = 0.0434). Progressive enhancement in the solid portion of the tumour was seen in 9 (81.8%) of 11 SPTs in male patients and in 30 (79.0%) of 38 SPTs in female patients on multiphasic CT.

CONCLUSION

The imaging features of SPTs in male patients usually appeared as a somewhat large-sized solid mass with a lobulated margin and progressive enhancement. These imaging features may help to differentiate SPTs from other pancreatic tumours for their proper management.

ADVANCES IN KNOWLEDGE

SPTs in male patients appear as somewhat large-sized solid masses with lobulated margins, and this form occurs more frequently in older male patients than in female patients.

Incidentally detected cystic lesions of the pancreas on CT: review of literature and management suggestions

PURPOSE

To facilitate a better understanding of incidentally noted cystic pancreatic lesions, since these lesions often pose a challenge regarding appropriate management.

METHODS

This article reviews pathophysiology, prevalence, significance, and recommendations for management of the various pancreatic cystic lesions. Illustrative cases are demonstrated.

RESULTS

Diagnostic benign lesions can be left alone. Cross-sectional imaging can be used to follow-up benign appearing lesions and to stage more aggressive ones. Endoscopic ultrasound with fine needle aspiration and cyst fluid analysis can be performed on certain indeterminate lesions. Lesions with high malignant potential should undergo resection.

CONCLUSIONS

A better understanding of the variety of incidentally detected pancreatic cystic lesions can help direct appropriate management.

Management of a malignant case of solid pseudopapillary tumor of pancreas: a case report and literature review

Solid pseudopapillary tumor of the pancreas is a rare neoplasm with low malignant potential, which affects predominantly young females. Only approximately 10% to 15% cases of solid pseudopapillary tumors (SPTs) are malignant. We present the case of a 57-year-old woman who developed malignant SPT of the pancreas. Meanwhile, a literature review was carried out. Some clinicopathological features and strategies of management of malignant SPT are presented. In general, surgical removal of the tumor even in case of metastases or recurrence offers an excellent prognosis. Chemotherapy and radiotherapy should be taken into consideration in patients with unresectable tumor.

Cystic tumors of the pancreas: imaging and management

Cystic tumors of the pancreas are a subset of rare pancreatic tumors that vary from benign to malignant. Many have specific imaging findings that allow them to be differentiated from each other. This article (1) reviews the imaging features of the common cystic pancreatic lesions, including serous microcystic adenoma, mucinous cystic tumor, intraductal papillary mucinous tumor, and solid pseudopapillary tumor, and including the less common lesions such as cystic endocrine tumors, cystic metastases, cystic teratomas, and lymphangiomas; and (2) provides comprehensive algorithms on how to manage the individual lesions, with recommendations on when to reimage patients.

[Pseudopapillary solid tumor of the pancreas: report of 6 cases]

BACKGROUND AND OBJECTIVES

Solid pseudopapillary neoplasms (SPNs) are rare tumours of the exocrine pancreas. Although they can develop metastasis, the prognosis is good. The aim of this study was to describe the characteristics of these tumours attended in our hospital.

PATIENTS AND METHOD

All cases of SPN in the database of the Pathology Department between 1991 and 2010 were included. Age, sex, symptoms, type of surgery, pathologic and immunohistochemical characteristics, and clinical evolution were analyzed.

RESULTS

Six cases were identified; all of them were women with a median age of 27.5 years. One patient presented haemoperitoneum, 2 abdominal pain and 3 were diagnosed incidentally. The most frequent localization was the pancreatic tail (n=4) and the median size was 7.7 cm. Four tumours were benign and 2 carcinomas. One of them had liver and lymph node metastases. Ki-67 proliferation index was low (1-3%). After a median follow-up of 33.5 months, all patients were alive and without evidence of relapse.

CONCLUSION

SPNs occur in young women. In most cases surgical resection is curative. A low mitotic index confers a good prognosis and a long survival.

Synchronous solid pseudopapillary neoplasm and intraductal papillary mucinous neoplasm of the pancreas: report of a case

Solid pseudopapillary neoplasm (SPN) of the pancreas, most commonly found in young female subjects, is a rare neoplasm with low potential for malignancy. We report an unusual case of a 66-year-old male patient who had a simultaneous malignant SPN and an intraductal papillary mucinous adenoma (IPMA) of the pancreas. The patient was admitted to our department for the evaluation of the main solid tumor with calcification and small multilocular cystic lesions apart from the main tumor in the pancreatic head. We performed pylorus-preserving pancreaticoduodenectomy to treat the calcified tumor and multilocular cystic lesions. The diagnosis of malignant SPN was confirmed on the basis of histological invasion to the adjacent structures. The separate cystic lesions were diagnosed as a branch-type IPMA. The synchronous occurrence of IPMA and SPN in the present case did not demonstrate that there were tumors maintained through the common abnormal Wnt signaling pathway by immunohistochemical study. To our knowledge, this is the first known case of synchronous SPN and IPMA of the pancreas.

MR imaging features of small solid pseudopapillary tumors: retrospective differentiation from other small solid pancreatic tumors

OBJECTIVE

The purpose of this study was to describe the MRI features of small solid pseudopapillary tumors useful for differentiating these tumors from other small solid pancreatic tumors.

MATERIALS AND METHODS

Forty-five patients (18 men, 27 women; mean age, 59 ± 11.7 years) with 45 solid pancreatic tumors smaller than 3 cm in diameter registered from 2000 to 2009 were included. Twenty-two of the tumors were adenocarcinomas, 12 were endocrine tumors, and 11 were solid pseudopapillary tumors. Two radiologists analyzed the MR images for morphologic features, signal intensity of the lesion on unenhanced images, and dynamic enhancement pattern. The contrast-to-noise ratio between the lesion and the pancreas was calculated on T1- and T2-weighted images and on dynamic images.

RESULTS

Solid pseudopapillary tumors commonly had the following features: completely well-defined margin (82%), pure solid consistency (82%), low signal intensity on unenhanced T1-weighted images (100%), high signal intensity on T2-weighted images (100%), a strong predominance among women (91%), and early heterogeneous and slowly progressive enhancement (100%). The solid pseudopapillary tumors rarely had a capsule or hemorrhage. A characteristic qualitative feature of solid pseudopapillary tumors that was significantly different from the other two tumor types was very high signal intensity on T2-weighted images (p < 0.01). Quantitative analysis showed that the solid pseudopapillary tumors had a lower contrast-to-noise ratio (-16.82 ± 5.84) on T1-weighted images and a higher contrast-to-noise ratio (37.35 ± 33.59) on T2-weighted images than did the other two tumor types (p < 0.01).

CONCLUSION

Small solid pseudopapillary tumors were predominantly seen as completely well-demarcated pure solid tumors in middle-aged women. They had lower signal intensity on T1-weighted images and higher signal intensity on T2-weighted images than did the other two tumor types and had early heterogeneous and progressive enhancement.

[MRI for malignant pancreatic tumors]

In recent years continuous advancements in software and hardware technology of modern MRI systems have contributed to substantial progress in the field of pancreatic tumor imaging. Despite technical advances in abdominal MRI, multislice CT still remains the preferential diagnostic tool for pancreatic lesions. In the majority of cases the essential clinical questions can thereby be answered with a high degree of accuracy. However, in dilemma cases state-of-the-art MR imaging can provide relevant information for the diagnosis allowing an optimal therapeutic concept. This report gives an overview on possible applications for MRI in the diagnostic evaluation of malignant pancreatic tumors.

Value of ultrasound examination in differential diagnosis of pancreatic lymphoma and pancreatic cancer

AIM: To investigate the value of clinical manifestations and ultrasound examination in the differential diagnosis of pancreatic lymphoma and pancreatic cancer.

METHODS: The clinical and ultrasonic characteristics of 12 cases of pancreatic lymphoma and 30 cases of pancreatic cancer were retrospectively analyzed.

RESULTS: Statistically significant differences were found in the course of disease, back pain, jaundice, carcino-embryonic antigen (CEA) and CA19-9 increase, palpable abdominal lump, superficial lymph node enlargement, fever and night sweats, lesion size, bile duct expansion, pancreatic duct expansion, vascular involvement, retroperitoneal (below the renal vein level) lymph node enlargement, and intrahepatic metastasis between pancreatic lymphoma and pancreatic cancer. There were no significant differences in age of onset, gender ratio, weight loss, nausea and vomiting, lesion position, the echo of the lesion, and the blood flow of the lesion.

CONCLUSION: Pancreatic lymphoma should be considered for patients with long lasting symptoms, superficial lymph node enlargement, palpable abdominal lump, fever and night sweats, relatively large lesions, and retroperitoneal (below the level of the renal vein) lymph node enlargement. A diagnosis of pancreatic cancer should be considered more likely in the patients with relatively short disease course, jaundice, back pain, CEA and CA19-9 increase, relatively small lesions, bile duct expansion, obvious pancreatic duct expansion, peripheral vascular wrapping and involvement, or intrahepatic metastases.