The clinical and radiologic manifestations of hemangiopericytoma

Molecular changes in solitary fibrous tumor progression

Abstract

Solitary fibrous tumors (SFTs) are NAB2-STAT6 fusion-associated neoplasms. There are several subtypes of NAB2-STAT6 fusions, but their clinical significances are still unclear. Moreover, the mechanisms of malignant progression are also poorly understood. In this study, using 91 SFT cases, we examined whether fusion variants are associated with clinicopathological parameters and also investigated the molecular mechanism of malignant transformation using whole-exome sequencing. We detected variant 1b (NAB2ex4-STAT6ex2) in 51/91 (56%) cases and variants 2a/2b (NAB2ex6-STAT6ex16/17) in 17/91 (19%) cases. The NAB2-STAT6 fusion variant types were significantly associated with their primary site (P < 0.001). In addition, a TERT promoter mutation was detected in 7/73 (10%) cases, and it showed a significant association with malignant SFTs (P = 0.003). To identify molecular changes during malignant progression, we selected an index patient to obtain parallel tissue samples from the primary and metastatic tumors. In the metastatic tissue, 10 unique molecular alterations, including those in TP53 and APAF1, were detected. In vitro functional experiments showed that APAF1 depletion increased the tumor potency of cells expressing NAB2-STAT6 fusion protein under treatment with staurosporine. We found that TP53 immunopositivity (P = 0.006) and loss of APAF1 immunoreactivity (P < 0.001) were significantly associated with malignant SFTs. Our study suggests that dysfunction of TP53 and APAF1 leads to impaired apoptotic function, and eventually contributes toward malignant SFT transformation.

Key messages

We firstly found that the TERT promoter mutation was strongly associated with malignant SFTs (P = 0.003) and the representative 1b (NAB2ex4-STAT6ex2) or 2a (NAB2ex6-STAT6ex16) fusion variants similarly contribute to tumorigenicity.

We also found that TP53 immunopositivity (P = 0.006) and loss of APAF1 immunoreactivity (P < 0.001) were significantly associated with malignant SFTs.

Our study suggests that dysfunction of TP53 and APAF1 leads to impaired apoptotic function, and eventually contributes toward malignant SFT transformation.

Electronic supplementary material

The online version of this article (10.1007/s00109-019-01815-8) contains supplementary material, which is available to authorized users.

Very rare localization of a retroperitoneal hemangiopericytoma revealed by lumbosciatalgia: A case report

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Hemangiopericytoma is a rare vascular tumor representing about 1% of all vascular tumors and approximatively 5% of all soft tissues sarcomas.

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Retroperitoneal hemangiopericytoma is a rare location.

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The radiologic feature suggests the diagnosis but the pathologic findings associated to immune histochemistery remain the only tool to confirm the diagnosis.

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Surgical excision is the most preferred treatment as it helps in relieving the symptoms as well as confirm the diagnosis.

Introduction: Hemangiopericytoma is a rare vascular tumor representing about 1% of all vascular tumors and approximatively 5% of all soft tissues sarcomas that arises from the pericytes of Zimmerman surrounding capillaries and postcapillaries vessels. Retroperitoneal hemangiopericytomas are rare among the localisations as it usually occurs in lower and upper extremities.

Presentation of case: We present a case of 31-year-old man with a well-defined retro peritoneal mass measuring about 105 × 73 × 83 mm at right lower quadrant of the abdomen anterior to right psoas muscle. Intraoperatively, an large mass measuring 10 × 8 cm was found arising from the retro peritoneum. A monobloc excision was performed. The postoperative course was uneventful. Histopathological examination with immune histochemistry revealed that tumoral cells were positive for desmin, CD34, smooth muscular antigen. Final diagnosis of hemangiopericytoma was made. On the last follow up at one year, he was symptom free.

Discussion: Hemangiopericytoma is a rare tumor. It takes origin from pericytes presenting as intervals along the walls of capillaries and post-capillary venules. Retroperitoneal hemangiopericytoma is a rare location. It is often discovered at late course, and can be revealed by various symptoms with the compression of the adjacent organs by the tumor Surgical resection should be considered in symptomatic cases or in case of diagnostic dilemma.

Conclusion: Retroperitoneal hemangiopericytoma can be benign but it should be treated the same way as aggressive tumors. It requires a careful and long term follow up.

The Peculiar Case of a Large Right Lower Quadrant Solitary Fibrous Tumor With Vasculature Arising from the Splenic Artery and Vein

We present the interesting case of a patient with peritoneal solitary fibrous tumor (SFT). The patient initially presented with right lower quadrant pain. Computed tomography findings revealed the presence of a large mass near the cecum, with both arterial and venous blood supply arising directly from the splenic artery and vein. The patient ultimately underwent surgical excision of the mass, and pathological examination was consistent with benign SFT. Not only is the location of our patient's tumor exceedingly rare, but also, to our knowledge, it is the first reported case of SFT with such a unique vascular supply.

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.

Hemangiopericytoma of the breast: a case report and a review of the literature

Introduction. Sarcomas of the breast are rare and hemangiopericytoma (HPC) of the breast is even rarer. Case Report. We report a case of a 43-year-old woman who presented with a 4 cm mass in her right breast. Her family history was positive for breast cancer. A fine needle aspiration indicated a malignant vascular tumor. An excision biopsy and frozen section analysis confirmed the presence of an encapsulated mesenchymal tumor. Its morphology and immunohistochemical marker profile were characteristic for a malignant hemangiopericytoma. Thus, she underwent a tumor excision without an axilla sampling. Approximately one year after the surgery the patient is well without local recurrence or metastasis disease to be observed. We also reviewed the literature and discuss the treatment options, characteristics, and immunophenotype of HPC. Conclusions. The accurate diagnosis of HPC depends on the appropriate histological and immunohistochemical examination. Surgical resection is the treatment of choice and due to scarcity of cases and unpredictable biological behavior of these tumors long term follow-up may be warranted.

Does histology predict outcome for malignant vascular tumors of the liver?

BACKGROUND AND OBJECTIVES

Malignant vascular tumors (MVT) of the liver are uncommon and poorly understood. We hypothesized that tumor histology is a predominant factor associated with survival in these tumors.

METHODS

Patients with malignant histopathologic diagnoses of hepatic angiosarcoma (AS), hemangioendothelioma (HE) and its epithelioid variant (EHE), or hemangiopericytoma (HP) were identified using the SEER database (1973-2007). Overall survival (OS) was studied with Kaplan-Meier curves.

RESULTS

We included 297 patients with MVT (207 AS, 28 HE, 56 EHE, 6 HP). All tumors demonstrated metastatic potential, although EHE and AS had the highest rate of regional or distant metastases (75% each). Patients with AS had the shortest median OS (1 month), however, those undergoing surgery had improved survival (6 months). Three patients with AS underwent liver transplant and lived for 11, 21, and 91 months each. Patients with EHE had the longest overall median survival of 75 months (30-183, P < 0.001). Surgical resection and transplant did not demonstrate an improvement in OS of patients with EHE in multivariable models.

CONCLUSIONS

Histology is an important factor in determining survival for patients with hepatic MVT. Patients with EHE have the longest OS, whereas patients with AS have shorter survival but may benefit from surgery.

The abdominal wall lumps and bumps: cross-sectional imaging spectrum

This article focuses on the cross-sectional imaging spectrum of abnormalities that affect the abdominal wall, with emphasis on magnetic resonance imaging (MRI). Cross-sectional imaging is valuable for diagnosing and evaluating the extent of abdominal-wall masses. With the increasing use of MRI, it is often possible to reach a diagnosis or narrow the differential diagnosis, thereby guiding effective management. Neoplastic and non-neoplastic pathologies will be illustrated, and the distinctive imaging characteristics of these entities will be highlighted.

Indeterminate soft-tissue tumors of the hand and wrist: a review based on a clinical series of 39 cases

Soft-tissue masses located at the hand and wrist are a frequent clinical presentation. The majority of these are ganglia, which have characteristic imaging features. Other common masses in which a diagnosis is suggested by imaging include hemangiomas, lipomas, and focal synovitis. The remainder are rare although a diagnosis may be attempted by considering the patients' age and the location. We reviewed 39 soft-tissue masses at the hand and wrist referred to our institution between September 1998 and January 2006 that had indeterminate imaging features. The majority were benign neoplastic lesions with the most common being a giant cell tumor of the tendon sheath, followed by angioleiomyoma, peripheral nerve sheath tumor, fibromatosis, fibroma of tendon sheath, and solitary fibrous tumor. These lesions tend to occur in young adults at the metacarpal level. However, there are no imaging features that can reliably differentiate between benign and malignant tumors.

Hemangiopericytoma of the neck

Hemangiopericytoma (HPC) is an exceedingly rare tumor of uncertain malignant potential. Approximately 300 cases of HPC have been reported since Stout and Murray described HPCs as "vascular tumors arising from Zimmerman's pericytes" in 1942. After further characterization, the WHO reclassified HPC as a fibroblastic/myofibroblastic tumor. Long term follow up is mandatory because the histologic criteria for prediction of biologic behavior are imprecise. There are reports of recurrence and metastasis many years after radical resection. The head and neck incidence is less than 20%, mostly in adults.

We report herein a case of HPC resected from the neck of a 74-year-old woman, who presented in our department with a painless right-sided neck mass. The mass was well circumscribed, mobile and soft during the palpation. The skin over the tumor was intact and normal. Clinical diagnosis at this time was lipoma. A neck computer tomography scan showed a large submucosal mass in the neck, which extended in the muscular sites. The tumor was completely removed by wide surgical resection. During surgery we found a highly vascularised tumor. The histopathologic examination revealed a cellular, highly vascularized tumor. The diagnosis was that of solitary fibrous tumor, cellular variant, with haemangiopericytoma-like features. The patient had normal postoperative course of healing and 24 months later she remains asymptomatic, without signs of recurrence or metastases.

[Solitary fibrous tumor of the abdomen. A rare neoplasm of vascular origin]

Solitary fibrous tumor (formerly known as hemangiopericytoma) is a rare soft tissue neoplasm, most frequently arising from the retroperitoneum and lower extremities. We present two cases of retroperitoneal solitary fibrous tumors diagnosed after surgical removal. We provide a literature review showing the basic clinical, pathologic and therapeutic features of these tumors.

Primary hemangiopericytoma of the liver: sonographic findings

Hemangiopericytoma (HP) is an uncommon vascular tumor that rarely develops in the liver. We present the case of a 68-year-old female with a primary HP involving the right lobe of the liver, detected during an abdominal screening sonography. The lesion was further evaluated using multidetector CT. The patient was treated with a right hepatectomy, and a pathologic diagnosis was made. Two years later, there was no evidence of recurrence.

Hemangiopericytoma of the Breast: A Case Report

BACKGROUND: Hemangiopericytoma (HPC) is a rare vascular tumor originating from the capillary pericytes, and HPC of the breast is extremely rare. CASE REPORT: We describe a 50-year-old woman with HPC of the breast and focus on the diagnosis before operation and the extent of the operation. Under local anesthesia, a complete tumor excision was performed. Then, the fast-frozen material was pathologically examined and the diagnostic conclusion was 'malignant tumor of the breast, perhaps original from lobus intermedius tissue'. Finally, a modified radical mastectomy was performed, after which all 7 lymph nodes from the axillary fossa position of the excision showed symptoms of reactive hyperplasia. CONCLUSION: ON THE BASIS OF REVIEWING THE LITERATURE ABOUT THE DISEASE, WE PROPOSE SEVERAL BASIC IDEAS: an accurate biopsy together with an appropriate histological and im-munohistochemical examination is promising, and since lymph node metastasis is extremely rare, a simple mastectomy may be considered.

Myopericytoma in Kager's fat pad

Myopericytoma is a recently described, rare, soft-tissue tumour with perivascular differentiation of myoid cells. We present a case of myopericytoma occurring around the ankle in a 68-year old man. The patient presented with a history of a lump around the ankle of 4 years' duration. Clinical presentation, radiological features and histopathologic findings of this case are reported, and the relevant literature is reviewed.

Giant atypical ossifying fibromyxoid tumour of the calf

We present a case of giant atypical ossifying fibromyxoid tumour (OFMT) of soft tissue, occurring in the calf, in a 77-year-old woman. The patient presented with a history of bleeding ulcer over a calf lump that had been present for over 4 years. Clinical presentation, radiological features and histopathologic findings are described, and the relevant literature is reviewed.

Duodenal hemangiopericytoma: CT and MRI findings

Hemangiopericytoma (HPC) is a rare mesenchymal tumor generally occurring in adults and originating from the pericytes. The tumor more commonly affects the soft tissues of the extremities, the pelvis, and the retroperitoneum. We describe the computed tomographic and magnetic resonance appearance of a patient affected by HPC of the duodenum.

Color and duplex Doppler sonography of hemangiopericytoma

We report the color Doppler sonographic features in a case of hemangiopericytoma of the thigh in a 52-year-old woman. Color Doppler sonography demonstrated the vascularity of the tumor, and spectral analysis showed waveform changes that suggested the presence of intratumoral arteriovenous shunting. The color Doppler findings correlated well with angiographic findings. Color Doppler sonography can demonstrate intratumoral arteriovenous shunting in hemangiopericytoma and may be used to help avoid profuse bleeding when performing a preoperative biopsy.

Vascular problems of the pelvis

Vascular tumors of the pelvis are a rare, diverse group of neoplasms. These benign or malignant tumors can arise from the endothelium, smooth muscle cells, or pericytes of the arterial venous or lymphatic walls. They are rarely diagnosed by physical examination but more commonly seen with imaging studies such as computed tomography, magnetic resonance imaging, or angiography. Benign and malignant tumors can be differentiated pathologically by the two major anatomic characteristics of vascular channel formation and the regularity of endothelial cell proliferation. This review will focus on the clinical presentation, diagnosis, treatment, outcomes, and surgical approaches to benign and malignant vascular tumors of the pelvis.

Hemangiopericytoma of the breast: mammographic and sonographic findings

The authors describe the mammographic and B-mode and color Doppler sonographic findings in a breast hemangiopericytoma in a 49-year-old woman. High vascularity was noted on color Doppler scans with the presence of a single vascular feeding pedicle. An update of the literature is included.

Hemangiopericytoma of the greater omentum: US and CT appearance

The US, Doppler and CT appearances in a patient with hemangiopericytoma of the greater omentum are presented. Ultrasound revealed a solid mass with heterogeneous echo pattern, well-defined margins and marked vascularity with low impedance flow (mean resistive index 0.42). The tumour was mobile. It was detected below the left kidney at the first US examination and had migrated into the pelvis 14 days later. At CT the tumour demonstrated strong but brief peripheral enhancement and a central hypodense scar.

Giant retroperitoneal hemangiopericytoma

Hemangiopericytomas are rare vascular tumours that are derived from pericytes. Retroperitoneal hemangiopericytomas are usually bulky but clinically silent when diagnosed because of their slow rate of growth. A 49-year-old man, who presented with only vague symptoms of abdominal fullness for several months, was found on computed tomography to have a huge well-defined mass with areas of low attenuation and well-enhanced septa. The tumour was successfully resected and was confirmed to be a malignant retroperitoneal hemangiopericytoma. It measured 30 cm in the greatest dimension. We are prompted to present this case as it is believed to be the largest tumour reported to date.

Hemangiopericytoma of the mediastinum causing spontaneous hemothorax

Mediastinal tumors rarely cause spontaneous hemothorax. We report a case of right-sided hemothorax that occurred in a 37-year-old woman with a hemangiopericytoma in the posterior portion of the superior mediastinum.