Conventional hemangiopericytoma: modern analysis of outcome

Total management of hemangiopericytoma/solitary fibrous tumor of the buttock: A case report

BACKGROUND

Solitary fibrous tumors can manifest at various anatomical sites, predominantly occurring at extrapleural sites with a peak incidence between 40 and 70 years. SFT necessitates long-term follow-up owing to its tumor characteristics. However, comprehensive reports covering the period from initial diagnosis to the patient's demise are lacking. Herein, we present a case of a malignant SFT of the buttocks that was treated at our hospital from the time of initial diagnosis to the end of life, with a literature review.

METHODS

A 54-year-old woman had a T1 low-to-isobaric and T2 isobaric-to-hyperintense mass in the psoas muscle on magnetic resonance imaging, diagnosed as an SFT. Wide excision was performed, followed by postoperative radiotherapy and chemotherapy. Multiple lung metastases were treated, while bone metastases appeared in the left femur. Multiple spinal metastases developed, causing respiratory distress due to pleural effusion. Best support care was initiated; however, a thrombus appeared in the inferior vena cava. Despite anticoagulant therapy, the patient died 11 years and 6 months after the initial surgery. Herein, marginal resection resulted in a relatively short operative time and average blood loss. The radiotherapy dose was 66 Gy; no complications occurred, and local recurrence was prevented. Tumor arthroplasty was performed to stabilize the affected limbs, and the patient required careful follow-up.

RESULTS

Despite the poor prognosis, the patient survived >11 years after surgery and had a favorable outcome.

CONCLUSION

Long-term monitoring for potential complications remains necessary.

Primary Omentum Malignant Hemangiopericytoma Present with Acute Abdomen

The greater omentum primary malignant tumors are rare, with less than 50 cases reported. Malignant hemangiopericytomas constitute only four of these cases. The common clinical manifestations of a malignant omental tumor are abdominal mass and pain. We report on a woman 38 years old who came to the hospital's emergency department with a finding consisting of intestinal obstruction (abdominal pain, constipation, abdominal distention, and vomiting), and during a clinical examination a mass was discovered in the lower half of her abdomen. She had been experiencing these symptoms for three days before her arrival. During a clinical examination, a large size, hard mobile mass was discovered in the lower half of her abdomen. The patient underwent an abdominal CT scan which indicated the presence of a sizable, soft tissue mass located within the abdominal and pelvic region, exerting pressure on the small bowel loops, with mild free ascites. Due to the patient's acute abdomen, an exploration laparotomy was performed, revealing a large mass in the omentum measuring 20×20×10 cm and weighing 3 kg. The mass, along with the omentum, was completely removed, and histopathology confirmed a malignant hemangiopericytoma.

Rare Encounter: Giant Hemangiopericytoma of Thigh in a Young Male

A rare tumor called hemangiopericytoma develops from the pericytes, the cells that surround blood vessels. They frequently grow slowly and might be asymptomatic initially. Although they can develop anywhere in the body, these tumors are most frequently found in the head, pelvis, and legs. This uncommon tumor originates in soft tissues like fat, muscles, tendons, nerves, blood vessels, and other fibrous tissues. The tumor in adolescence can be benign or malignant; it frequently develops in the bones but has the potential to metastasize to the lungs. Imaging tests, such as MRIs or CT scans, are commonly used in diagnosis to determine the location and size of the tumor. We present a case of a 23-year-old male who complained of swelling in his left thigh that had persisted for two years. He underwent multiple biopsies which were inconclusive until wide local excision of the swelling was done. On histopathology, the excised tumor was suggestive of hemangiopericytoma. The patient was advised of radiotherapy for completion of the treatment.

Surgical removal of an unusual huge solitary fibrous tumor in the mediastinum: a case report

BACKGROUND

Intrathoracic Solitary Fibrous Tumors (SFT) mainly arise from the pleura; however, these tumors may also originate from the mediastinum. We present a rare case of posterior SFT extending to several mediastinal sites and with an unusual large size, successfully treated with surgical resection.

CASE PRESENTATION

A 66-year-old female presented with an initial manifestation of ambiguous pain in the chest and dysphagia and later developed pitting edema in both lower extremities and cachexia five months before admission. Chest imaging confirmed a mediastinal mass (17 × 15 × 8 cm) which was surgically removed. Immunohistochemistry confirmed the diagnosis of a solitary fibrous tumor with positive B-cell lymphoma 2, STAT6, and CD99, negative S100 and smooth muscle actin, and low levels of Ki67 (5-7%). The patient's follow-up course was unremarkable.

CONCLUSION

Mediastinal SFTs may grow extremely huge, with the potential to invade multiple adjacent sites. Surgical removal of the tumor remains the mainstay of treatment in these cases.

Endoscopic endonasal resection of two rare cases of hemangiopericytomas invading the cavernous sinus and literature review

Hemangiopericytomas (HPCs) invading the cavernous sinus (CS) are extremely rare invasive tumors that have a great propensity for local recurrence. To date, only eight cases have been reported in the literature. Owing to the abundant vascular supply of HPCs, intracavernous bleeding and important blood vessels and nerves passing through the CS, it is very difficult and challenging for neurosurgeons to completely resect HPCs. Here, we report two cases of HPCs invading the CS and introduce their clinical manifestations, imaging findings, surgical approaches and histopathological features in detail. We have implemented the surgery by the endoscopic transpterygoid transcavernous approach (ETPTCa) for the two patients, and one patient has undergone gross total resection (GTR) and another has undergone subtotal resection (STR) and postoperative stereotactic radiosurgery (SRS). The ETPTCa may serve as a viable option to facilitate HPCs resection. Radiotherapy is helpful in prolonging progression-free survival (PFS) following STR of the tumor.

Management of pelvic sarcoma

Pelvic sarcomas are a rare and heterogenous group of tumors divided into two groups: soft tissue sarcomas and bone sarcomas. Soft tissue sarcomas of the pelvis include most commonly liposarcoma, leiomyosarcoma, gastrointestinal stromal tumors, malignant peripheral nerve sheath tumors, and solitary fibrous tumors. Bone sarcomas of the pelvis most commonly include osteosarcoma and chondrosarcoma. Multidisciplinary treatment at a center experienced in the treatment of sarcoma is essential. Management is dictated by histologic type and grade. Surgical resection with wide margins is the cornerstone of treatment for pelvic sarcomas, although this is often challenging due to anatomic constraints of the pelvis. Multimodal treatment is critical due to the high risk of local recurrence in the pelvis.

Case report: 125I seed implantation for rare malignant solitary fibrous tumor in the pelvic cavity: a case report

Solitary fibrous tumor (SFT) is a rare spindle cell tumor, benign or low-grade malignant, with an extremely low possibility of occurrence of malignant solitary fibrous tumor (MSFT). Surgery is an effective way for treating SFT, but it is often difficult to resect completely due to a large size, with a high recurrence rate and mortality rate after operation. Additionally, SFT is relatively resistant to chemotherapy, and there is a lack of effective systemic drug treatment. These lead to certain difficulties in the treatment of SFT. We report a case of a rare MSFT in the pelvic cavity. With a history of recurrence after two surgeries, this patient underwent surgical removal combined with ¹²⁵I seed implantation at our hospital in the context that the tumor could not be completely removed because it was large and adhered to surrounding tissues; after up to 43 months of progression-free survival (PFS), the patient underwent ¹²⁵I seed implantation alone, and achieved a complete remission, with a PFS up to 35 months. ¹²⁵I seed implantation can be a safe and effective treatment option for unresectable MSFT as well as a potential solution to repeated local recurrence.

Toward Better Understanding and Management of Solitary Fibrous Tumor

Solitary fibrous tumor (SFT) comprises a histologic spectrum of soft tissue neoplasms that are characterized by the unique NAB2-STAT6 gene fusion. Changes in diagnostic terminology and site-specific classification over the past few decades have resulted in a disjointed literature. Complete surgical excision with preservation of function remains the mainstay of treatment. New risk stratification systems including risk factors such as mitotic rate, age, tumor size, and presence of necrosis, among others, can be used to predict risk of recurrence or metastasis. Long-term follow-up after surgical resection is recommended. The clinical manifestations, diagnosis, management, and prognosis of SFT are reviewed here.

Multidisciplinary collaboration for the successful treatment of a giant hepatic solitary fibrous tumor protruding into the thorax: A case report

Solitary fibrous tumors (SFTs) are composed of spindle cells and collagen fibers, and these form rare mesenchymal tumors. SFTs are most frequently observed in intrathoracic sites; however, they may also occur in extrathoracic sites, such as the liver. Unlike the hepatic SFTs (HSFTs) reported in the literature, the SFT detailed in the present case report was a large tumor that originated from the liver, with a dumbbell-shaped growth through the diaphragm into the right thoracic cavity. This posed substantial challenges in both diagnosis and treatment. Thus, the present report outlines the findings of a multidisciplinary team meeting that was used to discuss and develop an optimal and personalized treatment strategy for the patient. Transhepatic arterial embolization was performed to block the major arterial blood supply to the tumor in order to reduce its size. Subsequently, the tumor was fully resected, following the collaboration of the experienced hepatobiliary and thoracic surgeons. Following surgery, the abdominal distension experienced by the patient ceased, and no tumor recurrence was detected at the 1-year follow-up. In conclusion, due to limited previous reports of HSFT treatment using multidisciplinary collaboration, the present study outlined the treatment used for this specific tumor type, and the corresponding literature was reviewed.

Hemangiopericytoma: Conducts and perioperative management of an extent sinonasal tumor in a Jehovah's Witnesses patient - Case report

Background

Hemangiopericytomas (HPCs) are rare tumors derived from mesenchymal cells with pericyte differentiation. About 5% of head and neck HPCs occur in the nasal cavity and paranasal sinuses. Due to its rarity, rich vascularity and variable biological behavior, its management is a challenge in itself.

Case

We report a case of sinonasal HPC in a Jehovah's Witness patient and discuss the obstacles and care related to the restrictions and therapeutic challenges involved in the approach to the patient. The patient was successfully treated by endoscopic endonasal approach with all per‐operative care and restrictions being respected and attended.

Conclusions

The management of HPC by itself involves challenges and when associated with other restrictive conditions attention and care are required.

Novel Therapeutic Options for Solitary Fibrous Tumor: Antiangiogenic Therapy and Beyond

SFT is an ultrarare mesenchymal ubiquitous tumor, with an incidence rate <1 case/million people/year. The fifth WHO classification published in April 2020 subdivided SFT into three categories: benign (locally aggressive), NOS (rarely metastasizing), and malignant. Recurrence can occur in up to 10-40% of localized SFTs, and several risk stratification models have been proposed to predict the individual risk of metastatic relapse. The Demicco model is the most widely used and is based on age at presentation, tumor size, and mitotic count. Total en bloc resection is the standard treatment of patients with a localized SFT; in case of advanced disease, the clinical efficacy of conventional chemotherapy remains poor. In this review, we discuss new insights into the biology and the treatment of patients with SFT. NAB2-STAT6 oncogenic fusion, which is the pathognomonic hallmark of SFT, is supposedly involved in the overexpression of vascular endothelial growth factor (VEGF). These specific biological features encouraged the successful assessment of antiangiogenic drugs. Overall, antiangiogenic therapies showed a significant activity toward SFT in the advanced/metastatic setting. Nevertheless, these promising results warrant additional investigation to be validated, including randomized phase III trials and biological translational analysis, to understand and predict mechanisms of efficacy and resistance. While the therapeutic potential of immunotherapy remains elusive, the use of antiangiogenics as first-line treatment should be considered.

Primary endodermal hemangiopericytoma/solitary fibrous tumor of the cervical spine: a case report and literature review

Background

Hemangiopericytoma (HPC), also known as solitary fibrous tumor (SFT), is a type of soft tissue sarcoma with a special aggressive behavior. The HPC/SFT is locally aggressive with possibility of late recurrence locally or distant extraneural metastasis. The most common location of this HPC/SFT is the lower extremities. The HPC/SFT in the central nervous system (CNS) is very rare, and compared with the brain, it is rarer in the spinal region. However, clinicians also lack an overall understanding of the diagnosis of HPC/SFT in the spinal cord.

Case presentation

In this study, we report a rare case of primary cervical spine HPC/SFT in a 53-year-old woman. Two to three weeks before admission, she experienced pain and numbness in her left upper extremity. After computerized tomography (CT) and magnetic resonance imaging (MRI), a gross total resection was performed. Obvious neurological improvement was observed postoperatively. The pain and numbness in the patient's left upper limb were relieved subsequently. We then reviewed the literature on HPC/SFT, such as its clinical presentation, imaging characteristics, treatment, and follow-up.

Conclusions

Diagnosis of HPC/SFT relies on magnetic resonance spectroscopy, enhanced CT, and MRI. Postoperative radiotherapy is strongly recommended to reduce the HPC/SFT recurrence. Immunohistochemical analysis can also help in the differential diagnosis. However; early and long-term follow-up is necessary for patients.

Presentation of Infantile Hemangiopericytoma/Solitary Fibrous Tumor as a Giant Extracranial Temporal Mass

Infantile Hemangiopericytoma (HPC)/Solitary Fibrous Tumor (SFT), a vascular tumor of head and neck region, can be congenital or arise during the first year of the life. As the infantile form of hemangiopericytoma has a better course than the adult form, surgical excision is recommended. Case Report: A full-term neonate presented with a congenital right temporal soft tissue mass. MRI revealed a highly vascular mass with a hemorrhagic and possible necrotic core without intracranial extension. The lesion grew in 2 weeks from 4x4 cm to 9x7 cm. Histologically, a hypercellular spindle cell mesenchymal neoplasm had prominent staghorn vessels, alternating with hypocellular areas. Mitotic activity was low(1-3/HPF) and necrosis was absent. Conclusion: Infantile HPC/SFT of head and neck can grow rapidly during the infantile period. Complete excision without mutilating surgery should be curative.

[Treatment of a patient with giant solitary fibrous tumor of the left hip]

The authors report surgical treatment of a 59-year-old female with a giant solitary-fibrous tumor of the left hip. Previous excision of hip hemangioma was performed in 2016. Recurrent tumor with fast growth has occurred since 2018. The neoplasm consisted of 2 tumors connected by vascular structures. CT revealed soft tissue neoplasms in the upper third of the left thigh (anterior, medial and dorsal regions). Large tumors with an isthmus along the inner surface had tuberous contours and internal septa. The last ones and walls accumulated contrast agent. No structural damage to femoral muscles was observed. The patient underwent resection of tumor and vascular ligation (great saphenous vein and its tributaries along the anterior surface, arteries from the deep femoral artery system along the posterior surface of tumor). There were no early postoperative complications. There are no complaints within 6 month after surgery. There is no lower limb dysfunction.

Doege-Potter Syndrome: A Presumptive Case of Metastatic Hemangiopericytoma with Persistent Hypoglycemia in a 27-Year-Old Male

Doege-Potter syndrome (DPS) is a rare paraneoplastic condition characterized by hypoinsulinemic hypoglycemia from a solitary fibrous tumor. The underlying mechanism is the secretion of a prohormone form of insulin-like growth factor II (IGF-II) by the tumor, which causes decreased release of glucose into the circulation. We report the case of a 27-year-old Filipino male with presumptive DPS from a recurrent right temporo-zygomatic hemangiopericytoma (HPC). The complexity of DPS requires a multidisciplinary approach. Early screening for metastases from HPC may prevent the undesirable sequelae of the disease process.

Two case reports of rare diseases occurring in rare parts: splenic vein solitary fibrous tumor and liver solitary fibrous tumor

Solitary fibrous tumor (SFT) is a rare soft tissue tumor originating from mesenchymal cells. Here we report two new cases of SFT. One case was a 37-year-old female patient whose primary tumor site was located in the splenic vein and the primary tumor resulted in splenomegaly and hypersplenism; its recurred for many times after surgical resection and eventually transferred to the liver, 4 operations were performed during 10 years of follow-up, and the patient is in a good condition right now. The second case was a 54-year-old male patient whose primary tumor site was located in the liver, spleen and left side of the chest wall. We performed two operations to remove these tumors, totally. Six years later, SFT recurred in the liver, given that the tumor was too large to be surgical resected completely, we chose orthotopic liver transplantation (OLT), and no tumor recurred during 6 years' follow-up, he is also in a good condition right now. The reports of these two cases of SFT are exceedingly rare, especially the splenic vein SFT is the first report case, which helps expand the understanding of SFT. Although the current mainstream treatment of SFT is surgical resection, liver transplantation may be a new option treatment for the huge liver SFT.

Malignant haemangiopericytomas of omentum presenting as left inguinal hernia: A case report

Background

Hemangiopericytomas (HPC) are vascular tumors and can be found at any place where vessels are present. These were previously known as ‘extrapleural Solitary Fibrous Tumour’. These tumors may reoccur and metastasize after surgical excision. We present herein a HPC of the greater omentum, diagnosed as left inguinal hernia preoperatively.

Case presentation

A 61-year-old male, presented with a huge painless mass in his left inguinoscrotal region secondary to weigh-lifting associated with malaise and vague abdominal pain. A well-defined, non-tender, and firm mass was found at the left lower abdomen extending to the left inguinoscrotal region. Based on the examination, a diagnosis of indirect inguinal hernia was made. Abdominal ultrasound showed a heterogeneous, hyporeflective, and vascularized mass. Contrast-enhanced computed tomography scan identified a localized, extraperitoneal, heterogeneously hypodense, well-defined, and lobulated mass, with marked contrast enhancement. On exploration, an encapsulated large mass originating from the omentum with enormously dilated blood vessels was excised. On histopathology, a neoplastic lesion, composed of spindle-shaped cells and moderate cytoplasm was identified. The blood vessels appeared thin-walled with a staghorn appearance in hemangiopericytic pattern. Omental sections showed fibro adipose tissue with dilated lymphatics and thick-walled blood vessels. Features were consistent with a malignant HPC of 20 × 14 × 10 cm.

Conclusion

We present an unusual presentation of primary omental malignant HPC as an inguinal hernia, treated by complete surgical resection. These tumors are rare therefore, timely diagnosis is important for proper evaluation, diagnosis, and treatment. It also requires long-term follow up for better survival.

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Hemangiopericytoma (HPC), previously known as ‘extrapleural Solitary Fibrous Tumor’, is a vascular tumor.

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A well-defined, non-tender, and firm mass was found at the left lower abdomen extending to the left inguinoscrotal region.

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Based on the examination, a diagnosis of indirect inguinal hernia was made.

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CT scan showed a contrast enhancing, localized, extraperitoneal, heterogeneously hypodense, and lobulated mass.

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On exploration, an encapsulated large mass originating from the omentum with enormously dilated blood vessels was excised.

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On histopathology, features were consistent with a malignant HPC of 20 × 14 × 10 cm.

Hemangiopericytoma: Incidence, Treatment, and Prognosis Analysis Based on SEER Database

Background

Hemangiopericytomas are rare tumors derived from pericytes surrounding the blood vessels. The clinicopathological characteristics and prognosis of hemangiopericytoma patients remain mostly unknown. In this retrospective cohort study, we assessed the clinicopathological characteristics of hemangiopericytoma patients, as well as the clinical usefulness of different treatment modalities. Material and Methods. We collected the clinicopathological data (between 1975 and 2016) of hemangiopericytoma and hemangioendothelioma patients from the Surveillance, Epidemiology, and End Results (SEER) database. Incidence, treatment, and patient prognosis were assessed.

Results

Data from 1474 patients were analyzed in our study cohort (hemangiopericytoma: n = 1243; hemangioendothelioma: n = 231). The incidence of hemangiopericytoma in 2016 was 0.060 per 100,000 individuals. The overall survival (OS) and cancer-specific survival (CSS) did not differ between patients with hemangioendothelioma and those with hemangiopericytoma (P = 0.721, P = 0.544). The tumor grade had no effect on the OS of hemangiopericytoma patients. Multivariate analysis revealed the clinical usefulness of surgery in hemangiopericytoma patients (HR = 0.15, 95% confidence interval: 0.05-0.41, P < 0.001). In contrast, radiotherapy did not improve OS (P = 0.497) or CSS (P = 0.584), and chemotherapy worsened patient survival (P < 0.001). Additionally, the combination of surgery and radiotherapy had a similar effect with surgery alone on hemangiopericytoma patient survival (OS: P = 0.900; CSS: P = 0.156). Surgery plus chemotherapy provided a worse clinical benefit than surgery alone (P < 0.001).

Conclusions

Our findings suggested that hemangiopericytoma had a similar prognosis with hemangioendothelioma. Surgery was the only effective treatment that provided survival benefits in hemangiopericytoma patients, while the clinical usefulness of adjuvant chemotherapy or radiotherapy was limited.

Solitary fibrous tumor of bone developing lung metastases on long-term follow-up

Solitary fibrous tumors are rare mesenchymal neoplasms of fibroblastic or myofibroblastic origin. Primary solitary fibrous tumors arising in bone are extremely rare and rarely metastasize. We present a case of solitary fibrous tumor where the diagnosis was delayed due to a failure to recognize the subtle, lytic lesion underlying a fracture of the left humerus. The patient underwent proximal humeral replacement and was followed closely with imaging of humerus and chest. A small lung metastasis was found on CT scan 38 months later and was resected. Two additional small metastases were found and resected 62 months after initial tumor resection. The purpose of this case report is both to highlight the radiologic challenges which can lead to overlooking a lytic lesion underlying a fracture and to show the importance of long-term follow-up in patients with solitary fibrous tumor.

Hemangiopericytoma of meningo-fronto-naso-orbito-maxillary complex

Hemangiopericytoma (HPC) is a rare vascular tumour and difficult to diagnose clinically. Incidence is reported in fourth to fifth decade of life.With female predominance, 3%-5% cases affect the oral cavity, sinus lining and meninges. The patient presented with 8×6 cm swelling on her face, evaluation reported it to be HPC. Bilateral maxillary artery embolisation, wide local excision of the lesion, preserving the left eye and its function, was done. No recurrence is reported at 1-year follow-up. Response of such lesions to radiotherapy is questionable; with no lymphadenopathy and adequate encapsulation, embolisation of feeder vessel followed by a wide local excision of the lesion seems to be a fairly good option of treatment.

Hepatic metastasis from a meningeal hemangiopericytoma: A case report

INTRODUCTION

A meningeal hemangiopericytoma (MHPC) is an aggressive tumor characterized by a high rate of local recurrence and late distant metastasis. The objective of this study was to share our experience with the treatment of a MHPC and how to distinguish this tumor from a meningioma.

PATIENT CONCERNS

A 62-year-old woman presented with symptoms of hypomnesia, hyperopia, and double vision for 1 month. Complete tumor excision was performed 6 years before. A biopsy sample was diagnosed as an atypical meningioma.

DIAGNOSIS

MHPC with late delayed hepatic metastasis.

INTERVENTION

Hepatic resection was performed initially, followed by secondary neurosurgery for complete excision of the bilateral frontal lesion 1 month later.

OUTCOME

Based on the tumor pathology and consensus of oncologic surgeons, radiation therapy was initiated. Adjuvant therapy was well-tolerated and the patient remained recurrence-free at 6 months after surgery.

CONCLUSION

Here, we report a case of local brain tumor recurrence and multiple hepatic metastases from a MHPC. Craniotomy combined with radical metastasectomy may be useful in such cases. Detailed immunohistochemical staining is helpful to distinguish a MHPC from a meningioma. Long-term follow-up is recommended.

Supraorbital Craniotomy for Sellar Solitary Fibrous Tumor: Operative Technique and Literature Review

OBJECTIVE

Solitary fibrous tumors (SFT) are rare, locally aggressive, mesenchymal neoplasms that pose both diagnostic and operative challenges. In this review of the literature, data were collected from all previously described sellar and suprasellar SFTs to date, with special attention paid to presenting symptoms, surgical technique performed, recurrence status, and adjuvant radiotherapy or chemotherapy, among others.

METHODS

A review of prior sellar and suprasellar SFTs was performed. Eleven cases of SFTs in the sellar and suprasellar regions were identified. We considered age and sex, along with case-specific information, such as presenting symptoms, surgical approach taken, number of resections, recurrence information, and adjuvant therapy.

RESULTS

All cases including ours presented with visual deficits, ranging from blurry vision to complete bilateral visual loss. Endocrine hormonal abnormalities occurred in nearly all patients (90%.) Craniotomy was performed more often than endonasal transsphenoidal resection of tumors, 42% versus 33%, respectively.

CONCLUSIONS

SFTs are slow-growing fibroblastic mesenchymal neoplasms that comprise <2% of all intracranial tumors. They are even more infrequently found in the sellar/suprasellar region, with our case being the 12th reported case of such and the first only to use supraorbital craniotomy as a resection strategy. Multimodal therapy consisting of safe gross total resection, radiosurgery, and/or chemotherapy provides the best possible results for these rare and locally aggressive entities.

Pelvic hemangiopericytoma: A case report and review of the literature

Extrauterine pelvic hemangiopericytomas are rare tumors with malignant potential. Herein, we report a case of a 55-year-old male who presented with hydronephrosis and obstructive urinary symptoms. Cystoscopy, imaging and biopsy were unable to provide a definitive preoperative diagnosis. He underwent pelvic mass resection, and final pathology revealed malignant hemangiopericytoma. The patient is being closely monitored with serial imaging, and remains disease-free at 23 months of post-operative follow-up without adjuvant therapy. Our experience and evidence from the existing literature suggests that given the rarity of these tumors, adherence to standard oncologic principles is necessary to ensure adequate resection and appropriate follow-up.

Quantitative assessment and clinical relevance of VEGFRs-positive tumor cells in refractory brain tumors

Vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR)1 and 2 signaling is a potent activator of tumor angiogenesis. Although the expressions of VEGFR1 and VEGFR2 were initially thought to be limited to the endothelial cells, it is now known that both the receptors are expressed in tumor cells. This is the first study wherein VEGFRs-positive tumor cells are quantitatively evaluated for brain tumors with upregulated VEGF/VEGFR signaling. The percentage of VEGFRs-positive tumor cells was quantitatively evaluated in various brain tumors (10 glioblastomas, 22 neurofibromatosis type 2 [NF2]-related schwannomas, 21 sporadic schwannomas, 27 chordomas, 36 meningiomas, 29 hemangioblastomas, 11 hemangiopericytoma, and 13 ependymomas) using immunohistochemistry. VEGF-A expression was also analyzed using quantitative real-time polymerase chain reaction. Double immunofluorescence staining using anti-PDGFR-β and anti-CD34 antibody, microvessel density, and vessel diameter were analyzed to evaluate the vascular characteristics. Chordomas demonstrated an extremely higher percentage of VEGFR1 and VEGFR2-positive tumor cells than other tumors. In contrast, meningiomas and hemangiopericytomas showed few VEGFRs-positive tumor cells. The percentage of positive tumor cells in chordomas, hemangioblastomas, and NF2 schwannomas was associated with clinical courses, such as shorter progression free survival, and growth speed. Glioblastomas and NF2 schwannomas showed larger tumor vessels without pericyte coverage. The present study is the first to quantitatively analyze VEGFR1- and VEGFR2- positive tumor cells in various types of refractory brain tumors. This novel parameter significantly correlated with the progressive clinical courses.

Pazopanib for treatment of typical solitary fibrous tumours: a multicentre, single-arm, phase 2 trial

BACKGROUND

Solitary fibrous tumour is an ultra-rare sarcoma, which encompasses different clinicopathological subgroups. The dedifferentiated subgroup shows an aggressive course with resistance to pazopanib, whereas in the malignant subgroup, pazopanib shows higher activity than in previous studies with chemotherapy. We designed a trial to test pazopanib activity in two different cohorts of solitary fibrous tumour: the malignant-dedifferentiated cohort, which was previously published, and the typical cohort, which is presented here.

METHODS

In this single-arm, phase 2 trial, adult patients (aged ≥18 years) diagnosed with confirmed metastatic or unresectable typical solitary fibrous tumour of any location, who had progressed in the previous 6 months (by Choi criteria or Response Evaluation Criteria in Solid Tumors [RECIST]) and an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 were enrolled at 11 tertiary hospitals in Italy, France, and Spain. Patients received pazopanib 800 mg once daily, taken orally, until progression, unacceptable toxicity, withdrawal of consent, non-compliance, or a delay in pazopanib administration of longer than 3 weeks. The primary endpoint was proportion of patients achieving an overall response measured by Choi criteria in patients who received at least 1 month of treatment with at least one radiological assessment. All patients who received at least one dose of the study drug were included in the safety analyses. This study is registered in ClinicalTrials.gov, NCT02066285, and with the European Clinical Trials Database, EudraCT 2013-005456-15.

FINDINGS

From June 26, 2014, to Dec 13, 2018, of 40 patients who were assessed, 34 patients were enrolled and 31 patients were included in the response analysis. Median follow-up was 18 months (IQR 14-34), and 18 (58%) of 31 patients had a partial response, 12 (39%) had stable disease, and one (3%) showed progressive disease according to Choi criteria and central review. The proportion of overall response based on Choi criteria was 58% (95% CI 34-69). There were no deaths caused by toxicity, and the most frequent adverse events were diarrhoea (18 [53%] of 34 patients), fatigue (17 [50%]), and hypertension (17 [50%]).

INTERPRETATION

To our knowledge, this is the first prospective trial of pazopanib for advanced typical solitary fibrous tumour. The manageable toxicity and activity shown by pazopanib in this cohort suggest that this drug could be considered as first-line treatment for advanced typical solitary fibrous tumour.

FUNDING

Spanish Group for Research on Sarcomas (GEIS), Italian Sarcoma Group (ISG), French Sarcoma Group (FSG), GlaxoSmithKline, and Novartis.

Extra-pleural solitary fibrous tumors: a review

Solitary fibrous tumor (SFT) is a rare mesenchymal ubiquitous tumor reported in the pleura and a wide variety of extrapleural locations, most frequently in the orbits and extremities.

Approximately 78–88% of SFTs are benign and 12–22% are malignant.

Although tumor characteristics are highly dependent on the location there are unifying features in MR imaging suggesting SFT: well-circumscribed, often lobulated nodular lesion, delayed contrast enhancement and the presence of fibrous contents which are hypointense on T1 and T2-weighted MRI imaging.

There are many SFT differential diagnosis, highly dependent to the tumor location. Due to its rarity the diagnosis of extrapleural SFTs may be challenging. Histopathologic analysis is always required to confirm the diagnosis and to allow the distinction between the benign and malignant forms.

We review pleural and extrapleural SFTs, presenting diagnostic clues, differential diagnosis and prognostic factors.

Case report: neonatal giant forehead hemangiopericytoma with a 5-year follow-up

RATIONALE

Hemangiopericytoma (HPC) is a rare pediatric neoplasm with a high risk of bleeding, aggressive growth and high early relapse rates. Surgical excision remains the mainstream treatment, while the functions of chemotherapy and radiotherapy remain controversial. In particular, an infantile giant extracranial HPC located in the forehead has never been reported.

PATIENT CONCERNS

A 3-day-old girl was delivered normally with a giant tumor localized mainly in the right frontal region. The surface of the mass was filled with vascularity.

DIAGNOSIS

According to the results of imaging and pathological examinations, the diagnosis was HPC grade II.

INTERVENTIONS

Gross total resection of the tumor and the invading partial frontal bone followed by skin scalp reconstruction was carried out without any blood transfusion.

OUTCOMES

No recurrence was identified during 5 years of follow-up. And better outcomes can be achieved without adjuvant therapy.

LESSONS

Multimodality imaging and a collaborative multidisciplinary approach are indispensable for the successful surgical management of infantile HPC, especially for giant tumors and their potential risk of life-threatening bleeding. Gross total resection is the optimal option for infantile HPC, and even without adjuvant therapy, it achieves better outcomes.

Safety and Efficacy of Hepatic Artery Embolization in Treating Solitary Fibrous Tumor Metastatic to the Liver

The aim of this study was to evaluate safety and survival following hepatic artery embolization (HAE) for metastatic solitary fibrous tumor (SFT) in the liver. All patients with SFT metastatic to liver treated with HAE were retrospectively analyzed. Tumor response was evaluated using mRECIST. Objective response, overall survival (OS), and progression-free survival (PFS) were evaluated using Kaplan–Meier and multivariate Cox proportional hazard ratio. Adverse events were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0. Twelve patients (6 males and 6 females, mean age: 42.5 ± 13 years; 24–65) were treated with 33 embolizations. Anatomical sites of origin for SFT were the head and neck (n = 6; 50%), pelvis (n = 2), pleura (n = 2), retroperitoneal (n = 1), and thigh (n = 1). The median follow-up from first HAE was 4.5 years (3–7.9). 84% of the patients showed objective response [42% complete response (CR) plus 42% partial response (PR)] to HAE by mRECIST (95% CI, 60–99%). Patients with CR to HAE had significantly higher OS compared to others (p < 0.02). The postembolization median OS was 4 years (95% CI, 2.3–5.2), and mean PFS, for intra- or extrahepatic progression of disease, was 6 months (95%, CI, 3.2–7.1). One patient developed pneumonia/sepsis and died 27 days postembolization, possibly not directly related to embolization. No grade III or IV adverse events were identified in the remaining patients. In conclusion, HAE for metastatic liver SFT is a relatively safe treatment option with high response rate and should be considered as a treatment option for metastatic liver SFT. In our cohort of patients with metastatic SFT to the liver, we observed a median OS of 4 years following HAE. Further studies are needed to confirm the efficacy of HAE.

Primary epidural hemangiopericytoma of the thoracic spine: Case report and literature review

Hemangiopericytoma (HPC) is a rare tumor originating from pericapillary cells. Rarely found in the central nervous system, it is extremely rare in the spinal canal. Because of the low incidence of this tumor, its radiographic features and clinical manifestations have not been extensively studied and reported, therefore, it is often misdiagnosed as a schwannoma or spinal meningioma. We describe an unexpected HPC in a 35-year-old woman who was admitted to the Peking Union Medical College Hospital with a severe backache, sensory abnormalities, and muscle weakness. Magnetic resonance imaging showed an enhancing lesion at T6-7 with severe compression of the spinal cord. Gross total resection was achieved, and subsequently, a marked neurologic improvement was observed. The diagnosis of primary extradural HPC in our patient was confirmed based on postoperative histopathology and immunohistochemistry. Neither recurrence nor metastasis of the tumor was found during the 14-month follow-up, which did not include radiotherapy. To describe the demography, radiologic features, treatment, and prognosis of spinal HPC, a comprehensive literature review was performed and 105 cases of primary spinal HPC from 1958 to 2017 were collected from 39 articles. Although rare, HPC should be considered in the differential diagnosis of intraspinal lesions. Immunohistologic examination is of decisive importance in making the diagnosis. Adequate surgical resection, when feasible, is the first choice of treatment for all cases of HPC; however, the outcomes of radiotherapy and chemotherapy have yet to be determined. Individualized treatment combined with long-term follow-up for each patient is recommended.

Haemangiopericytoma of the greater omentum: a rare tumour requiring long-term follow-up

Haemangiopericytomas (HPC) are highly vascularized tumours located in any part of the body where capillaries can be found. Since 2002, they have been re-classified under the umbrella 'extrapleural Solitary Fibrous Tumour (SFT)' and the term HPC is nowadays used to describe a growth pattern rather than a clinical entity. Their biological behaviour varies and they require a long-term follow-up since they may recur or metastasise several years after successful treatment. We present the case of a gentleman with HPC of the greater omentum initially appeared in 1998. HPC rarely develops in the greater omentum and only 20 cases have been described in the literature till today. Despite complete excision the mass re-appeared in 2011 and 2017, 13 and 19 years after initial treatment. Surgical management included en bloc excision of three lesions along with greater omentum. No further treatment was required.

Metastatic cervical paravertebral solitary fibrous tumor detected by fluorodeoxyglucose positron emission tomography-computed tomography

Solitary fibrous tumors/hemangiopericytomas (SFT/HPC) are soft tissue tumors that can arise from the abdomen, pleura, head and neck, or extremities. We report an unusual case of recurrent hemangiopericytoma in a 67-year-old female presenting with a painless and palpable mass within her right posterior neck. Eight years after initial resection of the mass, a follow-up MRI showed multiple enlarging calvarial lesions. A whole body FDG-PET/CT revealed not only hypermetabolic calvarial lesions but also numerous hypermetabolic axillary node and osseous metastases. Though the majority of these soft tissue tumors exhibit benign behavior and carry a favorable prognosis, patients with these slow growing tumors are at risk for local recurrence and distant metastases which demonstrate substantial FDG avidity. Additional studies are needed to clarify the role of whole body FDG-PET/CT in the surveillance of SFT/HPC to detect recurrent or metastatic lesions.

Solitary fibrous tumour of the mesentery: a case report

We present the case of a male with an asymptomatic abdominal mass, where imaging-guided biopsy confirmed the lesion as a solitary fibrous tumour arising from the mesentery. This is a notably rare location for solitary fibrous tumours with only a few reported cases in the literature.

Soft Tissue Solitary Fibrous Tumor: Combined Surgery and Radiation Therapy Results in Excellent Local Control

PURPOSE

To report survival outcomes and local control in patients with solitary fibrous tumors (SFT) treated using surgery and radiation therapy (RT).

METHODS

We reviewed the medical records of 31 consecutive patients definitively treated for SFT with surgery and RT between 1982 and 2012. The median age was 51 years (range, 23 to 88 y) and tumors were evenly distributed between the head and neck (n=9, 29%), trunk (n=10, 32%), and lower extremities (n=9, 29%). The majority of tumors were large (>5 cm) (n=23, 72%). Specimens had a median of 2 mitoses/10 HPF (range, 0 to 8). Nearly half the cases were treated with postoperative RT (n=14, 45%; median dose, 58 Gy) and the other 17 patients (55%) received preoperative RT (median dose, 50 Gy).

RESULTS

Median follow-up time was 59 months (range, 18 to 349 mo). The 5-year rates of local control, overall survival, and distant metastatic-free survival were 100%, 95%, and 92%, respectively. There were no local or nodal relapses and the 10-year complication rate was 6% (n=2).

CONCLUSIONS

Treatment of soft tissue SFT using combined surgery and RT results in excellent local control.

Hemangiopericytoma 11 years later: delayed recurrence of a rare soft tissue sarcoma

Hemangiopericytomas (HPCs) are uncommon tumours. We present the case of a 41-year-old female with multiple resections at different sites over the course of 11 years. The approach considerations, as well as treatment options and prognosis are discussed. A 41-year-old female with two previous resections for intracranial meningeal HPC in 2004 and 2008, as well as adjuvant radiotherapy, presented in 2015 with left intrathoracic and left hip recurrence confirmed by positron emission tomography/computed tomography (PET/CT). She underwent left proximal femur resection/reconstruction and video-assisted thoracoscopic surgery (VATS) resection of the intrathoracic tumour was attempted. She was discharged home on her 4th post-operative day with minimal pain. There were no neurosensory or motor deficits. Any patient who has been diagnosed with HPC in the past who develops new symptoms should be worked up for recurrence, regardless of the length of disease-free interval, as our case study suggested. There has yet to be a standardized follow-up regime due to the rarity of these tumours. HPC remains a rare soft tissue sarcoma with high recurrence rate. Planned VATS evaluation and resection is possible provided complete resection with clear surgical margins can be achieved, as clear surgical margins offer the best chance of survival.

Pancreatic metastasis from an osseous solitary fibrous tumour

A 73-year-old man presented with a right-sided chest wall mass that showed an epitheloid neoplasm with mild cytologic atypia on core needle biopsy. He underwent surgical resection, and final pathology revealed solitary fibrous tumour/hemangiopericytoma with negative margins. Three years after surgical resection, the patient presented with fatigue, abdominal pain, weight loss and mildly elevated liver function tests. Further workup revealed a 1.2 cm hypervascular mass in the neck of the pancreas. This case report summarises the surgical treatment and outcomes for a patient who presented with this rare tumour.

The Value of MRI and Clinical Features in Differentiating Between Cellular and Fibrous Solitary Fibrous Tumors

OBJECTIVE

The purpose of this study is to evaluate the usefulness of MRI in differentiating between fibrous and cellular solitary fibrous tumors (SFTs).

MATERIALS AND METHODS

This retrospective study included 17 patients with histopathologically confirmed SFTs, including 10 patients with fibrous SFTs and seven patients with cellular SFTs. We evaluated the differences between fibrous and cellular SFTs with regard to clinical data and MRI findings, such as tumor margin definition, signal intensity, heterogeneity on T1- and T2-weighted images, presence of capsules, intratumoral cystic changes, flow signal void, perilesional edema, enhancement pattern on dynamic contrast-enhanced MRI (DCE-MRI), and mean apparent diffusion coefficient (ADC) values.

RESULTS

Statistically significant differences in fibrous and cellular SFTs were noted with respect to signal intensity on T2-weighted images (p = 0.044, by Fisher exact test) and enhancement patterns on DCE-MRI (p = 0.005, by Fisher exact test). Specifically, on T2-weighted images, five of the fibrous SFTs had high signal intensity, and the other five had signal isointensity, whereas all seven cellular SFTs had high signal intensity. On DCE-MRI, fibrous SFTs tended to show a gradual increase in enhancement, whereas cellular SFTs showed a rapid initial enhancement pattern. The mean (± SD) ADC value for cellular SFTs was 1.39 ± 0.35 × 10^-3 mm²/s, whereas that for fibrous SFTs was 1.37 ± 0.48 × 10^-3 mm²/s, with no statistically significant difference noted between the two (p = 0.755, by Fisher exact test).

CONCLUSION

Fibrous SFTs have nonspecific findings with regard to signal intensity on T2-weighted MR images and enhancement patterns on DCE-MRI, whereas cellular SFTs show high signal intensity on T2-weighted images and rapid initial enhancement on DCE-MRI.

The demographic features, clinicopathologic characteristics, treatment outcome and disease-specific prognostic factors of solitary fibrous tumor: a population-based analysis

Background

Solitary fibrous tumor's (SFT) demographic features, clinicopathologic characteristics, treatment outcome and disease-specific prognostic factors were unexplored comprehensively.

Methods

SEER program was used to identify patients diagnosed with SFT from 1973 to 2012. Overall collected data were analyzed by using the SPSS 18.0.

Results

In total, 804 cases were found including 613 cases with SFT-specific mortality and 801 patients were analyzed for overall survival (OS). The 3-year disease specific survival (DSS), 5-year DSS and 10-year DSS were 73.3%, 65.7% and 53.3%. The 3-year OS, 5-year OS and 10-year OS were 71.9%, 63.3% and 47.3%. In the multivariate survival analysis, the age > 51 years (hazard ratio [HR] = 1.851 for DSS, P = 0.024 and HR = 1.652 for OS, P = 0.033; Reference [Ref] ≤ 51 years for DSS and ≤ 53 years for OS), SEER stage metastasized tumor (HR = 4.269 for DSS, P = 0.000 and HR = 2.905 for OS, P = 0.028, Ref - localized + regional tumor), pathologic grade III + IV (HR = 2.734 for DSS, P = 0.001 and HR = 2.585 for OS, P = 0.000, Ref - grade I + II) were adversely associated with DSS and OS. In addition, surgery was favorably associated with DSS (HR = 0.217, P = 0.045, Ref - surgery + radiotherapy).

Conclusions

The surgery was an independent prognostic factor for DSS. The patient's age, SEER stage and pathologic grade were SFT-specific independent prognostic indicators for DSS and OS.

Living-Donor Liver Transplantation for Hepatic Metastasis From Meningeal Hemangiopericytoma: A Case Report

We report the case of a 58-year-old man referred to our hospital for liver tumor treatment. The patient had a history of neurosurgery for a meningeal hemangiopericytoma 16 years previously. Pre-operative imaging revealed a hypervascular tumor extending from Couinaud segment 4 to segment 8 of the liver, measuring 95 mm in diameter, indicating an atypical hepatocellular carcinoma. Because right trisectionectomy of the liver was considered to be high risk, living-donor liver transplantation (LDLT) was indicated. After transcatheter arterial embolization, LDLT was performed with the use of a left-lobe liver graft from the patient's son. Post-operative histological findings of the liver tumor were identical to those for meningeal hemangiopericytoma, therefore the patient was diagnosed with meningeal hemangiopericytoma that had metastasized to the liver. After LDLT, the patient had a healthy, active life for 2 years; then, a subcutaneous relapse was discovered in the left chest. The patient did not undergo any systemic chemotherapy in response to the relapse. After thoracic and orthopedic surgeries and radiotherapy for multiple metastases, the patient died 5 years and 5 months after LDLT. LDLT could be an effective treatment for localized metastatic hemangiopericytoma in the liver, but it should be indicated only for carefully selected patients.

Hemangiopericytoma/solitary fibrous tumor of the greater omentum: A case report and review of the literature

INTRODUCTION

Hemangiopericytoma (HPC) has been first described in 1942 by Stout as a tumor originating from the capillary surrounding pericytes. It is known to occur in any anatomical site, especially the extremities and retroperitoneum.

PRESENTATION OF CASE

We describe a case of a 24year old patient presenting with lower abdominal pain due to a tumor of the greater omentum, the patient was treated by conventional laparotomy with tumor resection and the histological evaluation confirmed the diagnosis Hemangiopericytoma/Solitary fibrous tumor (HPC/SFT). The patient has regularly followed-up with periodic imaging for the last 4 years, with no recurrences.

DISCUSSION AND CONCLUSION

According to our knowledge, HPC rarely develops in the greater omentum, only 20 cases were described in the literature. Primary surgical resection is the treatment of choice. There is no benefit of radiation or systemic chemotherapy. Angiogenic inhibitors represent promising systemic therapeutic concepts.