Clinical characteristics and prognosis of primary leiomyosarcoma of the pancreas: a systematic review

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.

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.

Pancreatic leiomyosarcoma in a domestic shorthair cat

Case summary

A 7-year-old female neutered domestic shorthair cat was presented with weight loss, abdominal distension, lethargy, pyrexia and hyporexia. Haematology and biochemistry were unremarkable. Abdominal ultrasound revealed a cystic mass within the left cranial abdominal quadrant, adjacent to the pancreas, stomach and spleen. CT revealed a 10.5 cm, rounded, well-encapsulated, hypodense mass arising from the left pancreatic lobe. The remaining organs of the abdominal and thoracic cavity were unremarkable. A partial left lobe pancreatectomy and splenic lymph node removal were performed. Histopathology of the pancreatic mass reported a proliferating population of neoplastic spindle cells most consistent with a preliminary diagnosis of soft tissue sarcoma. Immunohistochemistry characteristics, together with the morphological findings, were consistent with a diagnosis of leiomyosarcoma. The patient recovered without any concerns after receiving routine postoperative care. Clinical examination and abdominal ultrasound 5 months postoperatively revealed no abnormalities.

Relevance and novel information

To our knowledge, this is the first report of pancreatic leiomyosarcoma in a cat. Pancreatic leiomyosarcoma should be considered as one of the possible differential diagnoses for cats presenting with a pancreatic mass.

Undifferentiated pleomorphic sarcoma of the pancreas: a rare case report and literature review

Background

Primary undifferentiated pleomorphic sarcoma (UPS) of the pancreas is an exceedingly rare malignant tumor, with only 15 cases have been reported in the medical literature. At present, clinicians have poor recognition of the tumor, the epidemiology, diagnosis, and treatment of this disease have yet not been established.

Case presentation

In this report, we depict the clinical and imaging characteristics of a 37-year-old man presenting with a primarily cystic UPS. The patient complained of epigastric pain and distention over 20 days. Abdominal CT and pancreatic magnetic resonance imaging revealed cystic and cystic solid masses in the pancreatic body and tail. An abdominal ultrasound echogram revealed the mass in the body of the pancreas to be cystic with separation echo inside, and the wall was thick, not smooth. Besides, a hypoechoic mass was seen in the tail area of the pancreas with an inhomogeneous echoic pattern, containing small patches of no echo zone in the central. Microscopically, spindle fibroblast-like cells are arranged in a characteristic storiform pattern with pleomorphic and multinucleated cells. Immunohistochemically, tumor cells were positive for CD68 and vimentin. Seven months postoperatively, he was diagnosed with pulmonary lymph node metastasis and died 5 months later. Combined with this case report, we also reviewed the literature regarding UPS of the pancreas.

Conclusions

As we know, this is the first report on ultrasonography findings of pancreatic UPS. Despite there are no distinctive manifestation of UPS, a solid cystic lesion on ultrasonography or a hypodense area in the lesion on T2-weighted imaging, should be considered for differential diagnosis with pancreatic UPS. We believe this article may add some ideas into the diagnosis and therapy of patients with this tumor.

Primary Pancreatic Leiomyosarcoma: A Rare Malignant Transformation of Primary Pancreatic Head Leiomyoma

Primary pancreatic leiomyosarcoma and primary pancreatic leiomyoma are rare tumors of the pancreas. Primary pancreatic leiomyoma is a benign tumor and its conversion to leiomyosarcoma has never been reported. We report a case of malignant transformation of pancreatic leiomyoma. In this case, a 75-year-old male, who presented with a mass in the head of the pancreas, was diagnosed with primary pancreatic leiomyoma. The patient maintained well on symptomatic treatment for 13 years. However, later the patient presented with loss of appetite, significant weight loss, and an abdominal lump, which was diagnosed to be locally advanced primary pancreatic leiomyosarcoma. The patient was provided the best supportive care and died after 11 months of diagnosis. Hence, we conclude that a more radical treatment approach is needed in patients with primary pancreatic leiomyoma.

Successful treatment of advanced pancreatic leiomyosarcoma treated with gemcitabine plus nab-paclitaxel: a case report and literature review

Pancreatic leiomyosarcoma (PLMS) is an extremely rare tumor that accounts for 0.1% of pancreatic malignancies, and its chemotherapy has yet to be established. Generally, soft-tissue sarcoma chemotherapy is standard treatment with doxorubicin (DXR) alone. However, the effectiveness of gemcitabine (GEM) plus docetaxel (DOC) has been shown in uterine leiomyoma. In contrast, the GEM plus nab-paclitaxel (PTX) regimen has been established as first-line chemotherapy for unresectable pancreatic cancer. For this study, we selected the GEM plus nab-PTX regimen for patients with PLMS, achieving success in approximately 10 months. From a search on PubMed, we found only 12 cases of PLMS (including this case) that underwent chemotherapy. Our case is the first reported patient to have survived more than 2 years with chemotherapy alone. In a nude mouse model, the GEM plus DOC regimen was shown to significantly decrease tumor size when compared with DXR in leiomyosarcoma, and the GEM plus nab-PTX regimen was reported to significantly reduce necrosis when compared with DXR alone, GEM alone, DOC alone, nab-PTX alone and GEM plus DOC in soft-tissue sarcoma. GEM plus nab-PTX therapy might therefore be the first choice for soft-tissue sarcoma and leiomyosarcoma. This is the first reported case of PLMS treated with GEM plus nab-PTX.

Pancreatic leiomyosarcoma: a diagnostic challenge and literature review

A 71-year-old woman was referred with abdominal pain and weight loss. An abdominal CT showed a 5-cm heterogeneous mass in the head of the pancreas with involvement of the superior mesenteric vein and artery. Her carcinoembryonic antigen (CEA) and CA 19-9 were normal. Two endoscopic ultrasound/fine needle aspirates (EUS/FNAs) of the mass diagnosed her with a mesenchymal tumour of myogenic origin but did not show features of malignancy. Frozen section analysis of laparoscopic core biopsies also failed to show malignant features, hence requiring an open biopsy which confirmed the diagnosis of pancreatic leiomyosarcoma (PLMS). She was eventually treated with radiotherapy. To our knowledge this is the only case in recent English literature of inoperable locally advanced PLMS that has required an open biopsy to formalise the diagnosis despite prior EUS FNAs. We include a review of the literature, highlighting the deficiencies of various biopsy techniques.

Irreversible electroporation in a case of pancreatic leiomyosarcoma: a novel weapon versus a rare malignancy?

Background

Primary pancreatic leiomyosarcoma is an extremely rare entity that needs high clinical suspicion in order to diagnose it at an early stage. Clinical characteristics, diagnosis, and management still remain challenging and controversial, especially in advanced stages, when tumor invades adjacent vessels and organs or gives distant metastases.

Case presentation

Herein, we describe a case of a 57-year-old woman suffering from advanced pancreatic leiomyosarcoma with thrombosis of the superior mesenteric vein, as well as liver lesions which were suspicious for metastasis. Multidisciplinary team decided for upfront chemotherapy to assess tumor response. Follow-up imaging after the completion of chemotherapy led tumor board to decide for subsequent surgical exploration. The patient underwent exploratory laparotomy and irreversible electroporation ablation of the pancreatic tumor. Postoperative course was uneventful, and she was discharged 10 days later with a plan to receive adjuvant therapy. To the best of our knowledge, this is the first case of pancreatic leiomyosarcoma ever reported, treated with this novel technique of irreversible electroporation that could be an alternative and feasible way for the management of these rare malignancies.

Conclusions

In conclusion, primary pancreatic leiomyosarcoma is a rare and highly malignant tumor associated with poor prognosis. Nowadays, R0 surgical resection remains the cornerstone treatment, combined with adjuvant and/or neoadjuvant chemotherapy prior to resection. In the advanced setting, when major vessel invasion and distant metastases occur, chemotherapy along with irreversible electroporation ablation could be a helpful and possibly effective modality for the management of this highly aggressive tumor.

Primary sarcomas of the pancreas: A review of 253 patients from the National Cancer Data Base

INTRODUCTION

Primary sarcomas of the pancreas are rare, and the limited data regarding their presentation, oncologic profile, and survival have been derived from small case series.

METHODS

The National Cancer Data Base (1998-2012) was queried for patients with primary sarcomas of the pancreas. Demographic and clinical features at the time of diagnosis were evaluated for all patients. Subjects who underwent surgical resection were identified, and logistic regression was used to identify variables associated with resection. A Cox proportional hazards model was developed to identify factors associated with survival.

RESULTS

In total, 253 patients were identified. The mean age at diagnosis was 63 years, with tumors occurring more frequently in women (57.3%) and those of white race (79.8%). Tumors in the head of the pancreas were most common (63.3%). The mean size was 7.5 cm. Only 100 patients (39.5%) underwent resection, with younger age (OR = 0.763, p = 0.04) and smaller tumor size (OR = 0.978, p < 0.01) associated with resection. Chemotherapy and radiation therapy use were similar in patients who underwent resection and those who did not. Patients who underwent resection had a median survival of 17 months, compared to 6 months for patients who were not resected (p < 0.01). Following adjustment, only older age (HR 1.257, p = 0.03) and higher tumor grade (HR 1.997, p = 0.01) were associated with an increased risk of death in resected patients.

CONCLUSIONS

Primary pancreatic sarcomas are rare and the majority of patients do not undergo resection; thus, little is known about their oncologic profile or outcomes following pancreatectomy. Patients who undergo resection have markedly improved survival; older age and higher tumor grade are associated with decreased survival.

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.

A case report of primary pancreatic leiomyosarcoma requiring six additional resections for recurrences

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Primary pancreatic leiomyosarcoma is extremely rare, and is considered to be a highly aggressive malignancy.

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We performed distal pancreatectomy, splenectomy, and wide resection of the transverse mesocolon.

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Due to treat recurrent tumors, six additional resections were needed over a 5-year period.

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Even if a primary pancreatic tumor recurs, long-term survival is achievable by repeated resection of recurrent tumors.

Introduction

Primary pancreatic leiomyosarcoma is extremely rare. We report a case in which six additional resections were required to treat recurrent tumors in a 5-year period following the primary operation.

Presentation of case

A 69-year-old man presented with a pancreatic tumor. Abdominal computed tomography scan showed a large heterogeneous mass with a necrotic area arising from the pancreatic body. We performed distal pancreatectomy, splenectomy, and wide resection of the transverse mesocolon. Histopathological examination confirmed the diagnosis of a pancreatic leiomyosarcoma. We repeatedly performed surgery on recurrent tumors.

Discussion

Primary pancreatic leiomyosarcoma is considered to be a highly aggressive malignancy. The most effective treatment is complete surgical resection with tumor-free margins. Even when tumors recur, it is possible to improve the prognosis by further resection.

Conclusion

Long-term survival is achievable by repeated resection of recurrent tumors.

Carcinosarcoma of the Pancreas: Case Report With Comprehensive Literature Review

Carcinosarcomas are rare biphasic neoplasms with distinct malignant epithelial and mesenchymal components. Most commonly, carcinosarcomas arise in the uterus as malignant mixed müllerian tumors, but also infrequently appear in other organs such as the ovaries and breast, the prostate and urinary tract, the lungs, or in the gastrointestinal system, among others. Pancreatic carcinosarcomas are exceedingly rare; only a few cases are reported in the English literature. Their pathogenesis remains to be fully clarified. We present here the case of a pancreatic carcinosarcoma with evidence for monoclonality via determination of Kras mutational status after microdissection and suggest a common origin of the 2 tumor components. Comprehensive review of the available literature allows the conclusion that most pancreatic carcinosarcomas appear to be of monoclonal origin and seem to have arisen from a carcinoma via metaplastic transformation of 1 part or subclone of the tumor, probably by epithelial-mesenchymal transition. All reported patients were treated with surgery. Adjuvant therapy, if administered, consisted predominantly of gemcitabine. Prognosis for this neoplasm occurs to be similar or even worse compared with classic pancreatic ductal adenocarcinoma. Despite the lack of evidence-based recommendations for its treatment, resection should be performed, if possible.

Primary Leiomyosarcoma of the Pancreas-a Case Report and a Comprehensive Review

Purpose

Primary mesenchymal tumors of the pancreas are rare, with leiomyosarcomas the most encountered entities among the pancreatic sarcomas. With few exceptions, single case reports published over the last six decades constitute the entire scientific literature on this topic. Thus, evidence regarding clinical decision-making is scant.

Methods

Based on a case report and an extensive literature search in PubMed, we discuss the clinical aspects and current management of this rare malignancy.

Results

We identified only two papers with more than a single case presentation; these institutional patient series were limited to five and nine patients. Additionally, a few papers sought to summarize the individual case reports published in the English and/or Chinese language. The clinical presentation is rather non-specific. Moreover, modern imaging modalities are insufficiently accurate to diagnose leiomyosarcoma of the pancreas. Treatment goals include a complete resection with free margins. Proper morphologic examination using immunohistochemistry and the application of a grading system are clinically important for prognostication. The efficacy of adjuvant treatments has not been established.

Conclusion

Primary pancreatic leiomyosarcoma is extremely rare, and the scientific literature is primarily based on single case reports. Conclusions on management and prognosis should be drawn with caution. A multidisciplinary team consultation is warranted to discuss a thorough individual treatment plan based on the available scientific literature, despite its low evidence level.

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 pancreatic leiomyosarcoma with metastasis to the liver diagnosed by endoscopic ultrasound-guided fine needle aspiration and fine needle biopsy: A Case Report and Review of Literature

Primary pancreatic leiomyosarcomas are rare tumors of the pancreas that are usually diagnosed after resection or by biopsy. One case in the literature has utilized endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) cytology. We report a second case of a primary pancreatic leiomyosarcoma that yielded diagnostic material on EUS-FNA cytology. A 72-year-old female presented with 3-4 months of abdominal pain. A CT scan showed a large heterogeneous, lobulated pancreatic head and uncinate mass and multiple hypoattenuating liver lesions. An EUS-FNA was performed on one of the liver lesions with a 25-gauge needle, yielding an adequate sample with lesional cells. The initial read was a spindle cell neoplasm. A subsequent endoscopic ultrasound-guided fine needle biopsy with a 22-gauge needle was performed on the pancreatic head mass to rule out two primaries and to provide tissue for a mitotic index in the case of gastrointestinal tumor. Both the cell block of the EUS-FNA and the core biopsy were equally cellular and showed interlacing spindle cells that stained positive for SMA and negative for DOG-1, CD 117, and CD34. In addition, the core biopsy of the pancreas stained positive for Desmin. A diagnosis of a primary pancreatic leiomyosarcoma was made and the patient was started on systemic chemotherapy. Primary pancreatic leiomyosarcomas are rare pancreatic tumors that may yield diagnostic material by EUS-FNA with a 25-gauge needle. Diagn. Cytopathol. 2016;44:1070-1073. © 2016 Wiley Periodicals, Inc.

RRM1, ERCC1 and TS1 Immunofluorescence Expression in Leiomyosarcoma: A Tissue Microarray Study with Clinical Outcome Correlation Analysis

ERCC1, RRM1 and TS1 are reportedly linked to chemotherapy resistance in lung and other cancers. However, there are currently no studies reporting the relationship between these genes and clinical parameters in leiomyosarcomas.

METHOD

This study investigated the expression pattern of ERCC1, RRM1 and TS1 in forty-four leiomyosarcoma samples by the use of tissue microarray (TMA), immunofluorescence and AQUA methods. The results were then analyzed for expression level and correlations were made with clinical outcome to determine their potential prognostic value in leiomyosarcoma.

RESULTS

In the forty-four samples studied, the expression level of these three proteins can be well quantified in the AQUA system and reflected by the AQUA score. RRM1 and ERCC1 expression levels did not show any relationship with overall survival. However, a correlation was found between TS1 expression in the cytoplasm and overall survival. The high expression group had a shorter overall survival time (log-rank p = 0.0498). This trend was confirmed by the Cox proportional hazards model.

DISCUSSION

The poor overall survival of leiomyosarcoma is linked to TS1 cytoplasm expression which may be useful in predicting prognoses of this tumor, methods targeting expression of TS1 may lead to improved overall survival in leiomyosarcoma, though more detailed information regarding treatment information and a larger sample size is needed to confirm this phenomenon.

Primary leiomyosarcoma of the pancreas: report of a case treated by local excision and review of the literature

Background

First described by Ross in 1951, primary pancreatic leiomyosarcoma is a rare mesenchymal tumour of the pancreas, with nonspecific clinical and radiological features and a poor prognosis, if unresectable.

Case report

A 60-year-old woman presented with abdominal pain. Magnetic resonance imaging (MRI) and computed tomography (CT) scan detected a dishomogeneous egg-shaped 8-cm mass, arising from the pancreatic head, with duodenal compression, without dilation of the Wirsung duct. ¹⁸F-FDG positron-emission tomography (PET)-CT showed a moderate tracer uptake, and the endoscopic ultrasound (US) showed a hypoechoic lesion, arising from the duodenal wall, suspected to be a gastrointestinal stromal tumour (GIST). CEA, CA19-9, NSE, and chromogranin A were normal. At the surgical exploration, a 10-cm mass, adherent to the anterior aspect of the pancreatic head, was found. The lesion was easily separable from the duodenal wall and was totally excised. The frozen intraoperative examination showed a mesenchymal tumour, with spindle-shaped cells, suggesting that a GIST diagnosis was likely. Postoperative course was uneventful. Histology and immunohistochemistry demonstrated a well-differentiated leiomyosarcoma, with five to six mitotic counts per 10 high-power field (HPF) and proliferative index (MIB-1) 10 % (grade 2 according to Federation Nationale des Centres de Lutte Contre le Cancer (FNCLCC)), with positive smooth muscle actin, desmin, and caldesmon but negative CD117 (c-kit) and S-100. The patient is alive and asymptomatic 19 months after surgery, without evidences of disease.

Conclusions

In the English literature, only 44 cases of primary pancreatic leiomyosarcoma have been reported. If a pancreatic mass suspected for primary pancreatic leiomyosarcoma has no adjacent organ/vessel invasion or distant metastases, surgical resection is the therapy of choice.