Extra-gastrointestinal stromal tumor of the pancreas: case report and review of the literature

Comments and illustrations of the European Federation of Societies for Ultrasound in Medicine guidelines: Rare pancreatic tumors, ultrasound and contrast-enhanced ultrasound features-Malignant mesenchymal tumors

Rare malignant mesenchymal pancreatic tumors are systematized and reported in this review. The focus is on the appearance on imaging. The present overview summarizes the data and shows that not every pancreatic tumor corresponds to the most common entities of ductal adenocarcinoma or neuroendocrine tumor.

Multiple Metastatic Extra-gastrointestinal Stromal Tumors with Plasmoid Differentiation: A Case Report and Review of Literature

Extra-gastrointestinal stromal tumors (EGISTs) are rare mesenchymal tumors that arise from the abdominal, pelvic or retroperitoneal region, unrelated to the gastrointestinal tract. However, cases with a plasmoid morphology are extremely rare. we hererin report a 49-year-old man with abdominal pain who underwent magnetic resonance imaging that revealed an irregular tumor (103×71 mm) in size, in the space between stomach and pancreas, diagnosed as an EGISIT, we also reviewed the clinicopathological characteristics and immunohistochemical characteristics, molecular genetic features and differential diagnoses previously reported in the literature.

CT, MR, and CEUS imaging features of recurrent GIST of the pre-sacral space: A case report

We present the case of a 50-year-old woman affected by a rectal gastrointestinal stromal tumor (GIST), with a recurrence in pre-sacral and pre-coccygeal space after surgery and Imatinib therapy. GISTs are the most common mesenchymal tumors of the gastrointestinal tract and rectal GISTs are rare (only 2% of cases); magnetic resonance and computed tomography are the main imaging techniques for diagnosis and follow-up, while ultrasound and contrast-enhanced ultrasound may be useful to perform a percutaneous biopsy, as in the case presented: the imaging features of the lesion in all these imaging methods are displayed.

Extra-gastrointestinal stromal tumor of the pancreas: A case report

Introduction

Presentation of case

Clinical discussion

Conclusion

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Pancreatic EGIST is extremely rare.

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There are no specific clinical and radiologic findings.

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Surgical resection is the cornerstone of the treatment.

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Whenever possible, enucleation is sufficient.

Rare Solid Tumor of the Exocrine Pancreas: A Pictorial Review

Numerous other solid primary neoplasms may arise from the pancreas besides primary ductal adenocarcinomas and neuroendocrine tumors. Although diagnosis can be difficult because of the very low incidence of these tumors, knowledge of several, typical, epidemiologic, biological, and imaging features can help obtain a correct diagnosis. This pictorial review describes the features of solid rare primary pancreatic neoplasms on computed tomography and magnetic resonance imaging focusing on characteristics that can help radiologists differentiate them from classical forms of ductal pancreatic adenocarcinoma and neuroendocrine tumors. Cystic pancreatic neoplasms are beyond the scope of the current review.

Nonepithelial Neoplasms of the Pancreas, Part 2: Malignant Tumors and Tumors of Uncertain Malignant Potential From the Radiologic Pathology Archives

Almost all neoplasms of the pancreas are derived from pancreatic epithelial components, including the most common pancreatic mass, primary pancreatic ductal adenocarcinoma (PDAC). Nonepithelial neoplasms comprise only 1%-2% of all pancreatic neoplasms. Although some may arise directly from intrapancreatic elements, many originate from mesenchymal, hematopoietic, or neural elements in the retroperitoneal peripancreatic space and grow into the pancreas. Once these tumors reach a certain size, it can be challenging to identify their origin. Because these manifest at imaging as intrapancreatic masses, awareness of the existence and characteristic features of these nonepithelial neoplasms is crucial for the practicing radiologist in differentiating these tumors from primary epithelial pancreatic tumors, an important distinction given the vastly different management and prognosis. In part 1 of this article, the authors reviewed benign nonepithelial neoplasms of the pancreas. This article focuses on malignant nonepithelial neoplasms and those of uncertain malignant potential that can be seen in the pancreas. The most common malignant or potentially malignant nonepithelial pancreatic tumors are of mesenchymal origin and include soft-tissue sarcomas, solitary fibrous tumor, and inflammatory myofibroblastic tumor. These tumors commonly manifest as large heterogeneous masses, often containing areas of necrosis and hemorrhage. The clinical features associated with these tumors and the imaging characteristics including enhancement patterns and the presence of fat or calcification help distinguish these tumors from PDAC. Hematopoietic tumors, including lymphoma and extramedullary plasmacytoma, can manifest as isolated pancreatic involvement or secondarily involve the pancreas as widespread disease. Hyperenhancing paragangliomas or hypervascular metastatic disease can mimic primary pancreatic neuroendocrine tumors or vascular anomalies.

Pancreatic Gastrointestinal Stromal Tumor: Clinicopathologic Features and Prognosis

GOALS

The present study aimed to investigate the clinicopathologic features and prognosis of pancreatic gastrointestinal stromal tumor (GIST).

BACKGROUND

Reports on clinicopathologic features and prognosis of pancreatic GIST are limited due to the extremely rare incidence.

STUDY

One case of pancreatic GIST from our center and 44 cases reported in MEDLINE were enrolled in this study. Clinicopathologic features and prognosis of pancreatic GISTs were analyzed and compared with 297 gastric GISTs from our center.

RESULTS

The most common location was head of pancreas (38.5%). The majority of pancreatic GISTs exceeded 5 cm (74.4%), displayed cystic or mixed imaging features (56.4%), and were high risk (85.7%). The 5-year disease-free survival (DFS) and disease-specific survival rates were 66.1% and 95.8%, respectively. Mitotic index was the only risk factor for DFS of pancreatic GISTs. The distribution of tumor size, histologic type and National Institutes of Health risk category were significantly different between pancreatic and gastric GISTs. The 5-year DFS rate of pancreatic GISTs was significantly lower than that of gastric GISTs. Multivariate analysis showed that location was an independent prognostic factor for DFS between pancreatic and gastric GISTs.

CONCLUSIONS

The most common location was head of pancreas. The majority of pancreatic GISTs were large and highly malignant. Pancreatic GISTs differed significantly from gastric GISTs in respect to clinicopathologic features. The DFS of pancreatic GISTs was worse than that of gastric GISTs.

GIST Manifesting as a Retroperitoneal Tumor: Clinicopathologic Immunohistochemical, and Molecular Genetic Study of 112 Cases

Most gastrointestinal stromal tumors (GISTs) occur in the tubular gastrointestinal (GI) tract, but some present apparently outside the GI tract. In this study, we analyzed 112 GISTs located in the retroperitoneum. These tumors occurred in 55 women and 57 men with a median age of 65 years (range: 21 to 89 y). On the basis of clinically or histologically detected connections to GI tract, 15 tumors were considered likely of gastric, 9 duodenal, and 13 of small intestinal origin. The remaining cases were categorized by location as peripancreatic (n=25), pelvic (n=11), mesenteric (n=4), and of unspecified/miscellaneous sites (n=35). The tumors varied in size 3 to 35 cm (median, 15 cm) and by mitotic rate per 5 mm, 0 to >100 (median, 10). Histologically the tumors apparently arising outside the GI tract had features of intestinal (n=41) and gastric GISTs (n=25); 9 cases had indeterminate histology. The histologic variants included spindled, epithelioid, vacuolated, nested, and myxoid potentially simulating other tumors such as liposarcoma and solitary fibrous tumor. Most GISTs were KIT-positive (106/112 cases), and the remaining 6 tumors were DOG1/Ano1-positive. Five cases showed focal nuclear positivity for MDM2. KIT mutations were detected in 42/59 cases, and PDGFRA mutations in 4/16 KIT wild-type and 3/5 of the KIT-negative tumors analyzed. One pelvic retroperitoneal GIST was succinate dehydrogenase deficient. All 79 patients were dead at last follow-up with a median survival of 14 months, with few survivals >5 years. Only operable versus inoperable tumor was a statistically favorable factor in univariate analysis (P<0.01). In multivariate analysis, mitotic rate >50/5 mm was significant for a shorter survival (hazard ratio, 5.25; 95% confidence interval, 1.65-16.8; P<0.01). Histologic and clinicopathologic similarity of extragastrointestinal retroperitoneal GISTs with GISTs of GI tract suggests their GI tract origin. Potentially overlapping features between GIST and other retroperitoneal tumors necessitate use of multiple diagnostic markers and molecular genetic studies.

Transdifferentiation of pancreatic stromal tumor into leiomyosarcoma with metastases to liver and peritoneum: a case report

Background

Primary pancreatic leiomyosarcoma is a rare pancreatic malignancy; the clinical presentation and treatment is not well-characterized. Further, the molecular mechanisms underlying its pathogenesis are not known. We report a patient with pancreatic stromal tumor that progressed to primary pancreatic leiomyosarcoma with hepatic and peritoneal metastases.

Case presentation

A 54-year-old woman was found to have pancreatic and hepatic tumor masses on routine health checkup. Owing to the difficulty in performing biopsy, this patient underwent open operation. Histopathological examination of pancreatic and liver biopsy specimen demonstrated spindle cells with nuclear mitoses. Immunohistochemical examination showed positive staining for Cluster of Differentiation117 (+) and negative staining for S-100 (-) and Smooth Muscle Actin (-). Thus, the patient was diagnosed as a case of advanced pancreatic stromal tumor with liver metastases. After surgery, treatment with oral imatinib mesylate combined with thymosin injection therapy was prescribed. Follow-up examination at 13-months revealed multiple nodular masses in liver and right peritoneum. The patient underwent a second surgery. Liver biopsy and the resected peritoneal specimen showed positive staining for Discovered On Gastrointestinal tumor-1(weak +), Actin (+), Smooth Muscle Actin (+) and negative staining for Cluster of Differentiation117 (-) Cluster of Differentiation34 (-) and S-100 (-). Histopathological examination showed spindle cells with nuclear mitoses. The final diagnosis was primary pancreatic leiomyosarcoma, transdifferentiating from pancreatic stromal tumor, with liver and peritoneal metastases.

Conclusions

Surgery is the first line treatment for primary pancreatic leiomyosarcoma and extra-gastrointestinal stromal tumors. In the present case, radical resection was not performed owing to hepatic metastases. Palliative treatment with radioactive ¹²⁵I ion implantation and microwave coagulation therapy was administered. However, the long-term therapeutic effect needs to be assessed in future.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2976-8) contains supplementary material, which is available to authorized users.

Primary mesenchymal tumors of the pancreas in a single center over 15 years

In total, 95% of primary tumors in the pancreas are epithelial tumors; primary mesenchymal tumors at this site are extremely rare. At present, only one comprehensive study about these rare tumors has been performed. Another retrospective analysis of these rare tumors is performed in the present study, which, to the best of our knowledge, is the first to be performed in China. In the present study, 10 patients that underwent resection for primary mesenchymal tumors of the pancreas were identified in a 15-year period at the Chinese Academy of Medical Sciences and Peking Union Medical College, which accounted for 0.51% of the total surgically resected primary tumors of the pancreas at this hospital. Among the 10 patients, 7 patients (70%) were diagnosed with benign/borderline tumors, and the remaining 3 patients (30%) were diagnosed with malignant tumors. It was a unique finding of the present study that the preoperative diagnosis was frequently a misdiagnosis, in terms of the specific pathological diagnosis. Therefore, although primary mesenchymal tumors of the pancreas are extremely rare, they should be considered in order to make the correct preoperative diagnosis. Contrarily to a previous study, in the present study, the most common benign tumor was not desmoid tumor, but solitary fibrous tumors; the most frequent primary sarcoma was not undifferentiated/unclassified sarcoma either. In conclusion, the present study aids the understanding of these rare tumors; however, primary mesenchymal tumors of the pancreas require additional exploration in the future.

Pancreatic GIST in a Patient with Limited Stage Small Cell Lung Cancer: A Case Report and Review of Published Cases

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract and usually occur in the stomach and the small intestine. The pancreas is an extremely rare primary site for GISTs and there are 25 reported cases of pancreatic GIST with most being treated with surgical resection. We describe a 52-year-old African-American female who was diagnosed with limited stage small cell carcinoma in November 2009 and treated with concurrent cisplatin/etoposide chemotherapy and radiation. She subsequently achieved complete remission. Two years later she was diagnosed with localized pancreatic GIST by endoscopic ultrasonography guided fine needle aspiration. We treated her with a tyrosine kinase inhibitor (TKI) imatinib 400 mg oral dose daily as she declined surgery. Her disease is stable based on computed tomography imaging scans 40 months after diagnosis without any metastasis. To the best of our knowledge, our case is the second case of localized pancreatic GIST treated with TKI monotherapy.

Coexisting and possible primary extra-gastrointestinal stromal tumors of the pancreas and liver: A single case report

Gastrointestinal stromal tumors (GIST) are mesenchymal neoplasms of the gastrointestinal tract (GI) that are defined, in part, by the expression of CD117, a c-Kit proto-oncogene protein. GISTs emerge outside of the GI at a very low frequency, typically in a single organ or location. GISTs that occasionally emerge outside of the GI are classified as extra-gastrointestinal stromal tumors (EGIST). The present study reports an extremely rare case of EGIST detected in the pancreas and the liver. The pancreatic and liver tumors were 4.5×2.5 cm and 2.0×1.5 cm in size, respectively. Both tumors consisted of CD117-positive spindle cells with a similar mitotic rate of 1–2 per 50 high power fields. The pancreatic and the hepatic EGISTs were at a low risk of malignancy, and both tumors were proposed to be primary stromal tumors. To the best of our knowledge, this is the first report of likely primary EGIST identified in the pancreas and liver of the same patient.

A rare combination between familial multiple lipomatosis and extragastrointestinal stromal tumor

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. Rarely, GISTs can be located in mesentery, retroperitoneal space, omentum or pancreas. In these cases, the neoplasm is defined as "extra-gastrointestinal stromal tumors" (EGISTs).

PRESENTATION OF CASE

We reported a case of a 63-year-old male patient diagnosed by computer tomography with large intraabdominal tumor with vague origin, postoperatively determined as an EGIST. The diagnosis was confirmed by immunohistochemical study. The patient had multiple, subcutaneous, painless lipomas localized in the arms, forearms, thighs, abdomen and thorax. Because of the family history and the clinical presentation the disease was determined as familial multiple lipomatosis (FML). We performed radical tumor resection with distal pancreatectomy and splenectomy, and abdominoplasty, removing redundant skin and underlying subcutaneous fat tissue with multiple lipomas.

DISCUSSION

FML is a rare hereditary benign disease. On the other hand, only few cases with familial GIST have been reported. In cases with extensive abdominal involvement, the primary origin of EGIST may be impossible to determine so the differential diagnosis is very difficult.

CONCLUSION

Although we could not prove correlation between the observed diseases, they are extremely rare and their combination is unusual which makes the presented case valuable and interesting.

Endoscopic ultrasound in the evaluation of pancreatic neoplasms-solid and cystic: A review

Pancreatic neoplasms have a wide range of pathology, from pancreatic adenocarcinoma to cystic mucinous neoplasms. Endoscopic ultrasound (EUS) with or without fine needle aspiration (FNA) is a helpful diagnostic tool in the work-up of pancreatic neoplasms. Its utility in pancreatic malignancy is well known. Over the last two decades EUS-FNA has become a procedure of choice for diagnosis of pancreatic adenocarcinoma. EUS-FNA is highly sensitive and specific for solid lesions, with sensitivities as high as 80%-95% for pancreatic masses and specificity as high as 75%-100%. Multiple aspects of the procedure have been studied to optimize the rate of diagnosis with EUS-FNA including cytopathologist involvement, needle size, suctioning and experience of endoscopist. Onsite pathology is one of the most important elements in increasing diagnostic yield rate in EUS-FNA. EUS-FNA is valuable in diagnosing rare and atypical pancreatic neoplasms including neuroendocrine, lymphoma and metastatic disease. As more and more patients undergo cross sectional imaging, cystic lesions of the pancreas are becoming a more common occurrence and EUS-FNA of these lesions can be helpful for differentiation. This review covers the technical aspects of optimizing pancreatic neoplasm diagnosis rate, highlight rare pancreatic neoplasms and role of EUS-FNA, and also outline the important factors in diagnosis of cystic lesions by EUS-FNA.

A Large Cystic Variant of Gastro-intestinal Stromal Tumour arising from the Jejunum: A Case Report

Gastrointestinal stromal tumours (GISTs) represent a mesenchymal neoplasm arising from the interstitial cells of cajal occurring mainly in the gastrointestinal tract. Here, we present a case of a large GIST arising from the jejunum with cystic presentation unlike the usual presentation as a solid mass. A 50-year-old male patient came with complaint of a painless mobile lump in abdomen of approximately 25 cm in size which had gradually increased over two years. Clinically mesenteric cyst was suspected. Intra-operatively the mass was a 30x25 cm cyst with approximately 2500 ml serous fluid present inside it arising from the anti-mesenteric border of the jejunum, adherent to the jejunum, appendix and the dome of the bladder. The fluid was aspirated and the mass excised along with resection of the involved jejunal segment and appendectomy was done. Diagnosis was confirmed on immunohistochemistry study. Imatinib Mesylate 400 mg OD was started as adjuvant therapy in view of the high risk of metastasis.