Recurrent intracranial solitary fibrous tumor initially diagnosed as hemangiopericytoma

Solitary Fibrous Tumor/Hemangiopericytoma Metastasizes Extracranially, Associated with Altered Expression of WNT5A and MMP9

Simple Summary

Meningeal/intracranial solitary fibrous tumor/hemangiopericytoma (icSFT/HPC) have a poor clinical outcome with metastatic behavior compared to soft tissue/extracranial SFT/HPCs (exSFT/HPC), but the underlying genetic factors are unclear. This study showed that WNT signaling, including WNT5A, was elevated in exSFT/HPC and MMP9 expression was higher in icSFT/HPC at both the mRNA and protein levels. Expression of CLDN5, a marker of endothelial tight junctions, was decreased in icSFT/HPC. The metastatic behavior of icSFT/HPC may be due to dysregulated angiogenesis and increased permeability of the vasculature caused by an altered WNT signaling pathway. Along with the increased expression of MMP9 in individual tumor cells, the combination of these effects will increase the probability of distant metastasis. Although exSFT/HPC and icSFT/HPC share a key molecular event, i.e., NAB2-STAT6 fusion, SFT/HPC may exhibit different biological properties and clinical courses depending on tumor location.

Abstract

Solitary fibrous tumor/hemangiopericytoma (SFT/HPC) is a mesenchymal tumor originating from various soft tissues and meninges, which carries the NAB2-STAT6 fusion gene. Meningeal/intracranial SFT/HPCs (icSFT/HPC) have a poor clinical outcome with metastatic behavior compared to soft tissue/extracranial SFT/HPCs (exSFT/HPC), but the underlying genetic factors are unclear. Differentially expressed genes (DEGs) were analyzed by NanoString nCounter assay using RNA extracted from formalin-fixed paraffin-embedded (FFPE) tissue samples. Additionally, immunohistochemistry (IHC) was performed on 32 cases of exSFT/HPC, 18 cases of icSFT/HPC, and additional recurrent or metastatic cases to verify the findings. Pathway analysis revealed that the WNT signaling pathway was enriched in exSFT/HPC. Analysis of DEGs showed that expression of WNT5A was lower and that of MMP9 was higher in icSFT/HPC than in exSFT/HPC (p = 0.008 and p = 0.035, respectively). IHC showed that WNT5A and CD34 expression was high in exSFT/HPC (p < 0.001, both), while that of MMP9 was high in icSFT/HPC (p = 0.001). Expression of CLDN5 in tumoral vessels was locally decreased in icSFT/HPC (p < 0.001). The results suggested that decreased WNT5A expression, together with increased MMP9 expression, in icSFT/HPC, may affect vascular tightness and prompt tumor cells to metastasize extracranially.

Intracranial solitary fibrous tumor mimicking meningioma: A case report

RATIONALE

Solitary fibrous tumor is a rare mesenchymal tumor. This case report describes the diagnosis and treatment of this tumor.

PATIENT CONCERNS

A 31-year-old patient presented with epileptic seizure and headache 1 day prior to the visit and showed transient right limb hemiplegia for 6 hours that was resolved after intravenous infusion of mannitol.

DIAGNOSES

Based on imaging, the provisional diagnosis was meningioma. Postsurgical histopathological diagnosis confirmed solitary fibrous tumor.

INTERVENTIONS

The lesion was totally excised. The patient improved remarkably after the operation, without any signs of associated limb movement disorder. No epileptic seizure was observed or reported after the operation.

OUTCOMES

Postoperation computed tomography (CT) scans showed no obvious residual tumor. The patient was followed up every 3 months for a total of 1 year following the operation, during which time the patient did not complain of headache or seizure.

LESSONS

The manifestation of solitary fibrous tumor (SFT) through imaging methods has certain specific findings,butimmunohistochemistry is still very important for confirming the diagnosis.

Cystic appearance - a new feature of solid fibrous tumours in the lacrimal gland: a case report with literature review

Background

Solitary fibrous tumours (SFTs) rarely occur in the orbit, especially in the lacrimal area. These tumours are mostly solid. Cystic changes have been documented, but they remain very rare. Only three cases of primary orbital solitary fibrous tumours with cystic changes have been reported in the literature, but no cases have been reported to occur in the lacrimal gland. Solitary fibrous tumours generally follow a benign course and are treated definitively with surgical excision. Data from the literature suggest that the cystic nature of SFT presents a risk of recurrence and could be a harbinger of malignancy.

Case presentation

A 42-year-old woman was admitted to the endocrinology department for right unilateral exophthalmia and epiphora in the last 8 months. An ophthalmological evaluation showed exophthalmia only in the right eye (22 mm) and normal visual acuity, visual field and extraocular movements. Investigations revealed normal thyroid function. Orbital magnetic resonance imaging detected a 4 × 2,2 × 2,7 cm septate pseudocystic mass in the right lacrimal gland. Given her lacrimal gland tumour diagnosis, the patient was submitted for neurosurgical intervention with total ablation of the tumoural mass and complete right dacryoadenectomy. Although the intraoperative extemporaneous examination results were suggestive of a haemangiopericytoma, histological and immunocytochemical examination showed an extrapleural SFT. The postoperative clinical evolution was favourable, with remission of the exophthalmia. Fifteen months after surgery, no signs of recurrence were noticed.

Conclusions

We report the first case of an SFT with cystic changes in the lacrimal gland. Although the presence of cavitary lesions alone does not necessarily indicate aggressive behaviour, cystic changes pose a risk of recurrence and may suggest malignant transformation over time. As a result, our case requires long-term follow-up due to recurrence and malignant potential.

Solitary Fibrous Tumors of the Orbit and Central Nervous System: A Case Series Analysis

Introduction:

Solitary fibrous tumor (SFT) is rarely diagnosed in clinical practice. Since its initial descriptions in the central nervous system (CNS) and the orbits, very few case reports and small case series have expanded their clinical and pathological characterization. We sought to describe a cases series of SFT from a single laboratory of neuropathology belonging to a tertiary university hospital.

Methods:

Retrospective clinical and histopathological description of eight cases of CNS and orbital SFT diagnosed over a 21-year period of time.

Results:

Median age was 47.3 years and four were males. Clinical presentation was related to local mass effect in all. Tumors occurred in the orbits (5/62.5%), intracranial dura attached (2), and the spinal medulla (1). The neuropathology showed the presence of hemangiopericytoma type (2), classic type (3), and mixed type (3). Histological anaplasia was present in two cases. Widespread/total immunoreactivity for vimentin, CD34, and Bcl-2 was present in all. Gross total removal was conducted in the majority (6/75%) and subtotal removal in 2 (25%). Three patients were submitted to adjuvant treatment (radiosurgery and radiotherapy). Recurrence occurred in four patients, 13–120 months after surgical intervention. Anaplasia was present in one case of recurrence.

Conclusion:

Our case series confirms the clinical and neuropathological diversity of CNS and orbital SFTs. Studies with longer follow-up periods are necessary to better understand the clinical behavior and prognosis of the SFT in the CNS and orbits.

Pediatric central nervous system solitary fibrous tumor: case report

INTRODUCTION

Solitary fibrous tumors are mesenchymally derived masses most commonly originating from the lung pleura.

CASE REPORT

Herein, we report a 6-month-old presenting with syndrome of inappropriate antidiuretic hormone secretion (SIADH) and a suprasellar mass. The mass proved to be a solitary fibrous tumor. This case and salient literature are reviewed.

CONCLUSIONS

To our knowledge, this is the youngest patient to be described with a mass of this type within the central nervous system.

Magnetic resonance imaging of intracranial hemangiopericytoma and correlation with pathological findings

The present study aimed to evaluate the radiological and pathological features of intracranial hemangiopericytoma, and improve the understanding of this tumor. A retrospective analysis of radiological and pathological features of five cases of intracranial hemangiopericytoma was conducted between 2006 and 2012 in the Second Xiangya Hospital of Central South University. A total of five cases (three males and two females; aged 37–60 years) were enrolled. Magnetic resonance imaging revealed that the lesions were lobulated with iso-intensity T1-weighted image signals and slightly long T2-weighted image signals. Cystic degeneration, necrosis and flow void were observed. The case with the lesion located under the tentorium cerebelli exhibited compression of the fourth ventricle with lateral ventricle dilatation hydrocephalus. In all cases, the solid section of the lesion was markedly enhanced following injection of the contrast agent, and intratumoral vessels were observed. No case exhibited the dural tail sign. Immunohistochemical examination revealed positive expression of cluster of differentiation 34(CD34), vimentin and CD99, and negative expression of epithelial membrane antigen, S100 and glial fibrillary acidic protein. Proliferating cell nuclear antigen Ki-67 immunohistochemical staining revealed that <5% of cells expressed Ki-67 in two cases and 5–10% of cells expressed Ki-67 in three cases. In conclusion, intracranial hemangiopericytoma exhibits certain distinctive characteristics in radiological examination, allowing for improved diagnosis. However, pathological examination is required for confirmation.

Haemangiopericytoma presenting with acute intracerebral haemorrhage--a case report and literature review

BACKGROUND

Intracranial haemangiopericytoma (HPC), a rare malignant tumour, should be distinguished from meningioma and solitary fibrous tumour, which have been considered as separate entities since 1993, according to histopathology and clinical characteristics.

METHODS

A PUBMED search for "Intracranial Haemangiopericytoma" yielded 176 articles, where 26 were of particular interest for this review article.

CASE REPORT

Our patient, a 27-year-old man with HPC of grade III according to WHO, presents with an acute intracerebral haematoma, which is extremely rare.

RESULTS

Surgery (total resection) is the primary treatment. Long-term close clinical and radiological follow-up is crucial due to the high rate of recurrence and tendency for development of metastasis.

DISCUSSION

The effects of postoperative radiotherapy need further investigation. Besides neurosurgery, radiotherapy should always be considered in both patients with these highly malignant tumours (WHO grade III) and in patients with partial resection or inoperable cases (WHO grade II).

Solitary fibrous tumor: an update on the spectrum of extrapleural manifestations

Solitary fibrous tumor (SFT) is a rare tumor initially believed to be a benign localized pleural tumor of mesothelial origin. Over the past few years, the literature on this tumor has grown tremendously. The tumor is now reported in diverse bodily locations, and recognized to have a wider range of clinical and radiological features. The most common extrapleural sites of the tumor are the orbits and the extremities. Tumors are often well-circumscribed masses, and vary in size from 1 cm to over 30 cm. The admixture of histological components in the tumor, namely, fibrous tissue, cellular components, and highly vascularized areas consisting of numerous closely packed small to medium-sized blood vessels, influence the imaging appearances of the tumor. On magnetic resonance imaging (MRI), the diagnosis of solitary fibrous tumor is suggested by a well-circumscribed mass that has smooth margins, and focal or diffuse hypointense signal on T2-weighted imaging due to fibrous content in the tumor. SFTs demonstrate strong focal or diffuse contrast enhancement due to the highly vascularized areas in the tumor.

Treatment of intracranial solitary fibrous tumors with gamma knife radiosurgery: report of two cases and review of literature

BACKGROUND AND IMPORTANCE

Gamma knife radiosurgery (GKRS) as a treatment option has not been described in the management of typical intracranial solitary fibrous tumors.

CLINICAL PRESENTATION

After presenting with visual decline, case A underwent a bioccipital craniotomy during which 90% of tumor was thought to have been resected. She unfortunately required re-resection 56 months later for recurrence when she again presented with progressive visual decline, altered mental status, and headaches. A subtotal resection was performed, because there was extensive tumor involvement of the torcula, straight sinus, and bilateral transverse sinuses. She was subsequently referred for GKRS. Although neurologically intact, with the exception of an upper extremity tremor, case B had undergone 7 surgeries for a posterior fossa tumor over the several decades preceding GKRS. The tumors targeted with GKRS were found on serial MRI scans and were thought to be asymptomatic at the time of treatment. At 7 and 14 months after GKRS, case A experienced tumor shrinkage, which remained stable 20 months after treatment. Effective local tumor control was seen in case B with tumor shrinkage at 3, 8, and 13 months after treatment. However, repeat GKRS was required for case B, because an out-of-field recurrence was found 15 months after the initial GKRS.

CONCLUSION

Based on this report and available information in the literature, radiosurgery appears to be a reasonable approach for patients with recurrent or residual intracranial solitary fibrous tumors.

Solitary fibrous tumors and hemangiopericytomas of the meninges: overlapping pathological features and common prognostic factors suggest the same spectrum of tumors

Meningeal solitary fibrous tumors (SFTs) and hemangiopericytomas (HPCs) are distinct entities in the World Health Organization (WHO) classification of central nervous system (CNS) tumors while they belong to the same spectrum of tumors in other locations. Well-defined histological prognostic factors are also lacking for these tumors. In order to clarify the relationship between SFT and HPC and to find histological and immunohistochemical prognostic factors, we carried out a retrospective study in 89 patients. The following histological parameters were recorded: hypercellularity, collagenic areas, cytonuclear atypias, necrosis, mitotic count per 10 high-power fields, vasculo-nervous adherences defined by engulfment of vessel or nerve by the tumor, brain infiltration. We found overlapping histological and immunohistochemical features between SFT and HPC. The most relevant histological prognostic factors in the whole cohort for both progression-free survival (PFS) and overall survival (OS) in univariate analysis were hypercellularity, high mitotic count (>5 per 10 high-power fields) and necrosis. On the basis of these results, we propose a new grading scheme for these tumors which was of pronostic value for both PFS and OS in uni- and multivariate analysis. As extent of surgery was also a prognostic factor for both PFS and OS in univariate analysis, we propose that management of SFT/HPC might be based both on quality of removal and histological grade.

Solitary fibrous tumor of the central nervous system: a 15-year literature survey of 220 cases (August 1996-July 2011)

We reviewed the world literature on solitary fibrous tumors of the central nervous system from August 1996 to July 2011, focusing on both clinicopathological features and diagnostic findings. The anatomical distribution of the 220 cases reported so far reveals that most are intracranial and just over one-fifth are intraspinal. In decreasing frequency, intracranial tumors involve the supratentorial and infratentorial compartments, the pontocerebellar angle, the sellar and parasellar regions, and the cranial nerves. Intraspinal tumors are mainly located in the thoracic and cervical segments. Although most solitary fibrous tumors of the central nervous system are dural based, a small subset presents as subpial, intraparenchymal, intraventricular, or as tumors involving the nerve rootlets with no dural connection. Preoperative imaging and intraoperative findings suggest meningioma, schwannoma or neurofibroma, hemangiopericytoma, or pituitary tumors. Immunohistochemistry is critical to establish a definitive histopathological diagnosis. Vimentin, CD34, BCL2, and CD99 are the most consistently positive markers. The usual histologic type generally behaves in a benign manner if complete removal is achieved. Recurrence is anticipated when resection is subtotal or when the tumor exhibits atypical histology. The proliferative index as assessed by MIB1 labeling is of prognostic significance. Occasionally, tumors featuring conventional morphology may recur, perhaps because of minimal residual disease left behind during surgical extirpation. Rare extracranial metastases and tumor-related deaths are on record. Surgery is the treatment of choice. Stereotactic and external beam radiation therapy may be indicated for postsurgical tumor remnants and for unresectable recurrences. Long-term active surveillance of the patients is mandatory.

Solitary Fibrous Tumor of the Central Nervous System

Solitary fibrous tumor (SFT) of the central nervous system was first described in 1996. A number of cases have been reported since. The authors present 5 new cases: 4 intracranial and 1 intraspinal. All patients were adults (age range, 47 to 75 years); 4 were male and 1 female; 4 cases were primary tumors; and 1 was a second tumor recurrence. All patients were surgically treated with gross total removal. All cases were histologically examined with immunohistochemical confirmation; 2 tumors exhibited diffuse classic histology, 1 tumor was a cellular variant, 1 tumor was myxoid, and 1 was predominantly classic with focal myxoid features and focally pleomorphic. The postoperative course was uneventful in all. The patient with the cellular variant experienced 2 local recurrences and eventually died of disease 10 years after the initial diagnosis. The patient with the myxoid variant—the tumor studied—which was the second recurrence of a previously misdiagnosed fibrous meningioma surgically treated 15 years earlier, had a recurrence after 2 years for the third time and eventually died of disease. Three patients are alive and well 11.6, 6, and 4 years after surgery. SFT is a rare tumor that needs to be differentiated from some mimickers, mainly fibrous meningioma, hemangiopericytoma, and with regard to the myxoid variant, also adult-onset myxochordoid meningioma and myxoid peripheral nerve sheath tumor. Immunohistochemistry is crucial for the correct diagnosis of SFT. The authors also performed a review of the literature and found a little more than 200 cases on record.

The central nervous system solitary fibrous tumor: a review of clinical, imaging and pathologic findings among all reported cases from 1996 to 2010

OBJECTIVE

Central nervous system (CNS) solitary fibrous tumor (SFT) is a rare lesion first identified as a unique entity in 1996. We describe two cases treated at the University of Florida followed by a review of all reported cases of CNS SFT between 1996 and 2010.

METHODS

A review of the literature was performed to identify all reported cases of CNS SFT.

RESULTS

189 cases (including the two presented herein) were discovered, of which 46 were spinal and 143 were intracranial. Demographic, imaging, and pathologic findings are presented. Roughly 6% of reported lesions are malignant. Subtotal resection (STR) was associated with a 16-fold increased odds of recurrence (OR 15.9, 95% CI 5.5-46.1), although mean follow-up was shorter in those cases of GTR without recurrence.

CONCLUSION

CNS SFT is a rare lesion. Six percent of lesions are malignant. GTR is superior to STR although the degree of superiority is not clear.

Undetermined fibrous tumor with calcification in the cerebellopontine angle

In this report, we introduce an undetermined fibrous tumor with calcification occurring in the cerebellopontine angle (CPA). A 51-year-old woman was admitted with a short history of dizziness. Computed tomography and magnetic resonance images revealed a 2×2×2 cm sized mass at the left CPA which was round and calcified. There was no dura or internal auditory canal involvement. At surgery, the tumor was located at the exit of 7th and 8th cranial nerve complex. It was very firm, bright yellow and well encapsulated. Histologic findings revealed that the tumor was predominantly composed of fibrous component, scant spindle cells and dystrophic calcification. Immunohistochemical staining demonstrated positive for vimentin and negative for epithelial membrane antigen (EMA), S-100 protein, CD34, factor XIIIa and smooth muscle actin. The diagnosis was not compatible with meningioma, schwannoma, metastatic brain tumors, and other fibrous tumors. Although the tumor was resected in total, long term follow-up monitoring is necessary due to the possibility of recurrence.

Malignant solitary fibrous tumor: report of 3 cases with unusual features

Malignant solitary fibrous tumor (MSFT) is a rare neoplasm. Three cases of MSFT with unusual features, including 1 pleural and 2 extrapleural, are reported. A 64-year-old woman with a large right thoracic MSFT and episodes of severe hypoglycemia experienced resolution of her hypoglycemia immediately after resection of the MSFT. A 27-year-old woman with primary retroperitoneal MSFT had pulmonary metastases 10 months after resection of the primary tumor. A 54-year-old man with an intracranial solitary fibrous tumor suffered from multiple pulmonary metastases and local recurrence 21 and 28 months after resection of the primary tumor, respectively. All 3 cases of solitary fibrous tumor displayed malignant features. The tumor cells in each case were positive for CD34 and Bcl-2, but negative for cytokeratin, smooth muscle actin, S-100, and c-kit. In addition, the tumor cells in the case with concomitant hypoglycemia were strongly positive for insulin-like growth factor-II. The histopathologic diagnostic criteria for MSFT, the differential diagnosis with other spindle cell tumors, and the mechanism of MSFT-derived hypoglycemia via insulin-like growth factor-II are discussed.