Orbital solitary fibrous tumor: radiographic and histopathologic correlations

Diagnostics and Treatment of Extrameningeal Solitary Fibrous Tumors

Solitary fibrous tumors (SFT) are rare mesenchymal neoplasms that account for less than 2% of all soft tissue masses. In the latest WHO 2020 Classification of Soft Tissue Tumors, extrameningeal SFT was listed as intermediate (rarely metastasizing) or malignant neoplasms. Due to the lack of characteristic clinical features, their diagnosis and treatment remain challenging. The pathogenesis of SFT is often associated with the presence of fusions of the NAB2-STAT6 gene on the 12q13 chromosome. Cytoplasmic CD34 positive staining is considerably characteristic for most SFTs; less frequently, factor XII, vimentin, bcl-2, and CD99 are present. A key factor in the diagnosis is the prevalent nuclear location of STAT6 expression. Radical resection is the mainstay of localized SFTs. In the case of unresectable disease, only radiotherapy or radio-chemotherapy may significantly ensure long-term local control of primary and metastatic lesions. To date, no practical guidelines have been published for the treatment of advanced or metastatic disease. Classical anthracycline-based chemotherapy is applicable. The latest studies suggest that antiangiogenic therapies should be considered after first-line treatment. Other drugs, such as imatinib, figitumumab, axitinib, and eribulin, are also being tested. Definitive radiotherapy appears to be a promising therapeutic modality. Since standards for the treatment of advanced and metastatic diseases are not available, further investigation of novel agents is necessary.

Orbit Solitary Fibrous Tumor: A Proposed Risk Prediction Model Based on a Case Series and Comprehensive Literature Review

Solitary fibrous tumors (SFTs) of the orbit are rare. In order to further characterize the clinical and pathologic features of solitary fibrous tumor arising at this anatomic site, 12 cases of orbital SFTs were analyzed in conjunction with a review of 263 cases reported from the English literature in order to develop a risk prediction model. SFTs of the orbit were equally distributed between males (n = 5) and females (n = 7) with a mean patient age of 46.8 years (median 44.5 years; range 18-76 years) at initial diagnosis. The patients typically presented with swelling or mass around the orbit, with proptosis (n = 10), ptosis (n = 5), and visual changes (n = 6). Tumors were orbital (n = 10) or upper eyelid (n = 2). Mean tumor size was 2.5 cm (median 2.6 cm). Microscopically, the tumors were characterized by cytologically bland spindle cells with patternless growth, hypocellular and hypercellular areas, variable amounts of collagen, and ectatic, branching blood vessels. By immunohistochemistry, all cases had a strong nuclear STAT6 expression. All patients were initially managed with excision or biopsy, three with presurgical embolization. The two patients with biopsy only had persistent disease (mean 37.2 months), but a third patient developed distant bone metastasis at 86.9 months. Overall mean follow-up was 73.1 months: 9 patients are alive or dead without disease (mean 77.9 months), two patients with persistent disease, and one patient with metastatic disease at last follow-up (102 months). Incorporating cases sufficiently reported in the literature, a risk prediction model based on age > 45 years, tumor size > 3 cm, tumor necrosis, mitoses of > 4/2 mm2, moderate to high cellularity, and moderate to severe pleomorphism allows for risk stratification for the development of local recurrence and distant metastasis. In conclusion, orbital SFTs are rare, but can be reliably diagnosed based on the presence of characteristic morphologic features and STAT6 immunohistochemistry. Orbital tumors tend to show a higher frequency of local recurrence than distant metastasis, which can be predicted by a risk stratification model unique to orbital tumors. With late disease common, long term clinical follow-up is recommended.

Clinical correlation recommended: accuracy of clinician versus radiologic interpretation of the imaging of orbital lesions

Purpose: To assess the accuracy of radiographic interpretation between the clinician and radiologist when compared to histopathology of orbital lesions. Methods: A retrospective chart review of patients at the University of California Davis Eye Center who underwent orbitotomy from 1/1/2000 to 5/22/2019 was performed. Charts with a preoperative imaging report, preoperative clinical assessment including the clinician's interpretation of imaging, and histopathologic diagnosis were included. The specific diagnoses were grouped into related classes of pathology for the analysis. The clinical and radiologic assessments were compared against the final histopathologic diagnosis for concordance. A concordance analysis was performed. Results: 242 patients (mean age 49 years, 53.5% female) were reviewed. Of these records 185 documented the clinician's clinical impression, the radiology report, as well as the histopathology report. The clinician's preoperative assessment had substantial agreement [kappa = 0.72 (0.65,0.79)] with the final histopathologic result and was correct in 75.7% (140/185) of cases whereas the radiology report was correct in 52.4% (97/185) with a moderate level of agreement [kappa = 0.47 (0.39, 0.55)]. In 49.2% (91/185) of cases the final histopathology correlated with both the clinical impression and radiology report [kappa = 0.58 (0.55, 0.61)]. Conclusions: The accurate interpretation of orbital imaging is a challenge and histopathologic examination remains the gold standard for diagnosis. While orbital imaging is a valuable diagnostic tool the interpretation of these studies is most accurate when conducted in the context of the patient's medical history, clinical exam, and with the physician most familiar with various orbital lesions.

Solitary Fibrous Tumors: 2016 Imaging Update

Optimal management of solitary fibrous tumor requires a multidisciplinary approach with proper histopathological mapping and use of various imaging modalities for exact delineation of primary tumor and metastatic disease if present. In this article, the authors present a comprehensive review of the spectrum of imaging findings of solitary fibrous tumors involving various organ systems and discuss the role of molecular targeted therapies in the management of metastatic disease.

Ocular adnexal (orbital) solitary fibrous tumor: nuclear STAT6 expression and literature review

PURPOSE

To report the clinico-pathological features of solitary fibrous tumor occurring in the ocular adnexa (OA) in a single center. To assess the presence of NAB2-STAT6 genes fusion in OA solitary fibrous tumor detected by nuclear overexpression of STAT6.

METHODS

Retrospective study including orbital and OA solitary fibrous tumors treated between 2006 and 2014 in our center. The clinical, radiological, and histopathological findings were evaluated. STAT6 expression was assessed by immunohistochemistry.

RESULTS

Five patients were identified and presented with a chronic OA mass. The tumors were radiologically well delimited, highly vascularized and without bone erosion. All the patients underwent complete surgical excision. Pathological examination confirmed solitary fibrous tumor in all cases. All tumors demonstrated a nuclear expression of STAT6. There were no recurrences, with a mean follow-up of 5 years after surgery. Our review demonstrated that proptosis was the most common presentation occurring in 60 % of the cases. In the ocular adnexa, adverse histological criteria were found in 19.7 % of the tumors, and recurrences were observed in 48 % of these cases. Thirty-six percent of patients presented at least one local recurrence, and metastastic spread was found in 2.4 % of the cases. Tumor-related death was described in two cases.

CONCLUSION

Ocular adnexal SFT are rare and usually present as a chronic orbital mass with proptosis. In the OA, solitary fibrous tumor demonstrates STAT6 nuclear expression, as documented in other locations. Recurrences are unusual and metastasis exceptional. Initial surgical resection should be complete in order to avoid recurrence.

Orbital solitary fibrous tumor: a case series with review of the literature

PURPOSE

To report the clinical features, patient demographics, management, and outcomes of a series of patients with orbital solitary fibrous tumors (OSFTs) and provide a review of the English literature describing this rare entity.

DESIGN

A review of patient demographics, clinical presentations, imaging, histopathology, surgical management, and outcomes were analyzed.

METHODS

A non-comparative retrospective chart review of the demographics, clinical presentations, imaging, histopathological features, management, and disease outcomes of patients presenting to a tertiary orbital center with a tissue diagnosis of OSFT between 2007-2012 was performed along with a review of the English-language literature.

RESULTS

Our study included four male patients, with a mean age of 48 years at referral. The most common presentations included a slowly growing mass, globe displacement, diplopia on extreme gazes, and/or facial disfiguration. All tumors were analyzed with histopathology and immunohistochemistry. Treatment involved the complete surgical excision of the lesion, obtaining clear margins. All patients remain alive and well with no evidence of recurrence after a minimum follow-up of 15 months (range 15 months-5 years).

CONCLUSION

SFTs should be considered when confronting a painless slowly growing orbital mass that induces globe displacement and/or facial deformity. Imaging will show a well-defined lesion that enhances with contrast. A careful initial surgical excision with clear margins is required for adequate local control of the tumor, avoiding recurrence and potential malignant transformation.

Intraorbital metastasis from solitary fibrous tumor

Solitary fibrous tumor (SFT) is a rare spindle cell tumor of mesenchymal origin that usually arises from pleura or pericardium but can also arise from many extraserosal sites. Although more than 50 cases of primary SFT of the orbit have been reported, there are no reports to date of a malignant nonophthalmic SFT metastasizing in the orbital soft tissues (although sphenoid wing bony involvement has been reported). The authors report here the first case of a patient with intraorbital metastasis of a CD34-positive malignant SFT. The patient was a 57-year-old man with a history of malignant pleural SFT and a prior kidney metastasis. He presented with the rapid appearance of proptosis and massive conjunctival chemosis preventing eyelid closure, and he was found to have a well-circumscribed metastasis to his lateral rectus muscle. Surgical excision cured his ocular symptoms, although he died 3 months later from brain and widespread metastases.

Correlation between clinical features, imaging and pathologic findings in recurrent solitary fibrous tumor of the orbit

PURPOSE

To correlate clinical features, imaging and pathologic findings in recurrent Solitary Fibrous Tumor of the orbit (SFT) in order to predict long-term behavior.

METHODS

Clinical features, imaging and pathologic findings of three patients with biopsy proven SFT are reported. Demographic and clinical features were recorded at presentation and at each consultation; imaging was performed as a diagnostic tool and for follow-up. A biopsy was performed at presentation and subsequently when symptoms worsened. Pathology specimens were reviewed retrospectively to corroborate diagnosis. Intraoperative and histopathologic features were recorded. A correlation was made between clinical, imaging and pathologic results to identify outcome predictors of recurrence, locally aggressive behavior and malignant transformation.

RESULTS

All cases presented recurrent tumors with locally aggressive behavior over time. All were women in the fifth decade of life. Tumors induced proptosis, swelling of the lids and eye displacement at presentation and were diagnosed as other types of collagen-rich tumors before CD34 immunohistochemistry was available. Mean follow-up was 26.6 years (range 12-37). Relevant findings for all cases included a heterogeneous, irregular tumor containing cystoid spaces filled with mucoid material diffusely enhancing with imaging techniques. Intraoperative findings included a gelatinous matrix within the center of the tumor mass, which was not present at primary resection. Histopathology could not detect specific cellular patterns or immunological markers related to these changes.

CONCLUSIONS

Recurrence and locally aggressive behavior was better predicted by imaging and surgical findings rather than histopathological characteristics. Cystoid degeneration in recurrent tumors may suggest malignant transformation over time.

MRI study of solitary fibrous tumor in the orbit

OBJECTIVE

Solitary fibrous tumor (SFT) is a rare lesion of the orbit. The purpose of this study is to determine the MRI features of orbital SFTs.

MATERIALS AND METHODS

We retrospectively reviewed 15 patients with histopathologically proven orbital SFTs. All patients underwent orbital MRI. The location, size, shape, margin, and MRI signal of 15 lesions were reviewed. The time-intensity curve (TIC) of dynamic contrast-enhanced MRI in 14 patients and diffusion-weighted imaging in four patients were also analyzed.

RESULTS

Ten orbital SFTs were located in the extraconal space (seven at the superior aspect and three at the lateral aspect), three in the retrobulbar intraconal space, one in the superomedial aspect of the intraconal space, and one in the lacrimal sac region. All SFTs appeared ovoid in configuration and had well-defined margins. The mean maximum diameter was 30.2 mm (range, 15-56 mm). Fourteen SFTs appeared homogeneously isointense to gray matter on T1-weighted images. On T2-weighted images, the lesions showed heterogeneous isointensity in nine patients and hypointensity in five patients. The lesions showed heterogeneous marked enhancement on contrast-enhanced MRI. Streaky high-signal-intensity areas on T2-weighted images with marked enhancement were observed in nine patients. Flow-void signal was identified in six patients. The TICs of 14 patients showed a washout pattern. The contrast index was 1.61±0.42, the time to peak enhancement was 34.15±14.04 seconds, and the washout ratio was 37.32%±14.37%. The mean apparent diffusion coefficient value of four patients was 1.28±0.23×10(-3) mm2/s. Another case exhibited multicystic appearance.

CONCLUSION

Isointense or hypointense signal on T2-weighted images, marked enhancement, and a washout TIC pattern are the characteristic MRI features of orbital SFTs.

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.

Malignant solitary fibrous tumor of the nasal cavity

Solitary fibrous tumors (SFTs) are unusual mesenchymal tumors that were first described as primary spindle-cell neoplasms of the pleura. These tumors have been described in many other locations, including the urogenital system, orbit, mediastinum, and upper respiratory tract. Twenty-two cases of an SFT of the paranasal sinuses and nasal cavity have been reported, but none described a malignant SFT extending through the anterior skull base. A 70-year-old man had a 6-month history of unilateral left-sided epiphora and nasal obstruction. Computed tomography and magnetic resonance imaging showed a large left-sided nasal cavity mass with extension into the left extraconal orbit and intracranial extension through the left cribriform plate and ethmoid roof. The patient underwent preoperative embolization of the internal maxillary artery and a subsequent anterior craniofacial resection via a midfacial degloving approach and a left anterior craniotomy. Histopathological analysis of the specimen was consistent with a malignant SFT.

[Mesenchymal orbital tumors]

Mesenchymal tumors grow from pluripotent mesenchymal cells that form the soft orbital tissue. Primary tumors of the orbital walls are discussed in another section. Tumors from muscle and adipose tissue are rare or exceptional, except rhabdomyosarcoma, described in the section dedicated to pediatric tumors. Most frequent tumors are fibrous histiocytomas and solitary fibrous tumors, which often have a retrobulbar location. Fibrous histiocytoma is benign in only 65 % of cases. Fibrous solitary tumor is now better known (Ag CD34): this tumor is generally benign but frequently recurs.

Orbital solitary fibrous tumor. Another rare case from Africa

Solitary fibrous tumor (SFT) of the orbit, initially thought to be rare, is being increasingly documented in the medical literature. We here present the case of a 37-year-old Nigerian man who presented with left sided painless, vision-sparing proptosis. Cranial computed tomography scan showed a globular, left medial, orbital extraconal mass. The mass was excised, en bloc, via a medial orbitotomy procedure aided by left ethmoidectomy. Surgery was uncomplicated and histology of the excised tissue was reported as compatible with SFT. There was also a strong and diffuse immunostaining with CD 34. At 6-month follow-up, the left-sided proptosis has completely regressed. To the best of our knowledge, this is the second case of orbital SFT to be reported in an African.

Orbital giant cell angiofibroma recurring as a solitary fibrous tumor

Giant cell angiofibroma has recently been hypothesized to be a clinicopathologic variant of solitary fibrous tumor. The authors report a case of an orbital giant cell angiofibroma that recurred as a solitary fibrous tumor 4 years later. The report strongly supports the hypothesis that giant cell angiofibroma and solitary fibrous tumor are related.

Tendon sheath fibroma of the medial canthus

Isolated fibromas of the ocular adnexa are rare. Fibromas of the tendon sheath (FTS) are benign, collagenous, spindle cell neoplasms that typically present as an acquired, painless mass in the adult extremities. They infrequently involve the head and neck. We report a case of FTS presenting as a medial canthal mass. Like most FTS, the lesion in our patient was successfully treated by complete surgical excision. While the differential diagnosis contains a variety of mesenchymal tumors, the clinical and radiographic characteristics should lead to the correct diagnosis. To our knowledge, this is the first case of FTS reported to arise at this site.

Solitary fibrous tumor of the orbit: Morphological, cytogenetic and molecular features

Solitary fibrous tumor (SFT), a benign neoplasm arising in mesenchymal structures, was initially described in the pleura but subsequently has also been documented in other locations. It is uncommon in the orbit, where it closely resembles other benign spindle-shaped mesenchymal tumors of this area such as schwannoma, meningioma or hemangiopericytoma. We present a case of orbital SFT in a 34-year-old woman. The radiological study showed the presence of an enhanced uptake lesion measuring 2 cm in major diameter. The histopathological evaluation revealed alternating cellular and hypocellular areas with spindle-shaped cells. The cellular organization displayed a broad variety of irregular morphological patterns. The neoplastic cells were intensely positive for CD34 and vimentin, while S100, epithelial membrane antigen (EMA), Caldesmon, Calretinin and WT-1 proved negative. The pericellular matrix exhibited strong positivity for CD44 and collagen IV. Scarce mitotic figures, a Ki-67 nuclear labeling index of <5%, and focal expression of p53 were also observed. Measurement of DNA content revealed a DNA index of 1, indicating a diploid peak in 95% of the tumor cells. A normal 46,XX karyotype was present. No TP53 (exons 5-8) mutations or MDM2 and CDK4 amplifications were observed. No p14(ARF), p15(INK4B) and p16(INK4A) deletions or hypermethylation were observed in this benign tumor. Following surgical resection and radiotherapy, the patient showed no tumor relapse after one year of follow-up.

Solitary fibrous tumor of the orbit: a case report

Solitary fibrous tumor is a very rare neoplasm affecting the head and neck. We present a case located in the orbit in which clinical, pathological and surgical features are reviewed.

Unusual Solitary Fibrous Tumors in the Central Nervous System: A Report of Two Cases

Solitary fibrous tumors (SFTs) are uncommon, and most are found in the pleura. Extrapleural SFTs are rare and have been found in the lung, pericardium, mediastinum, soft tissue of any site, and upper respiratory tract. SFTs of the central nervous system (CNS) are very rare. The biologic features are unknown and remain poorly understood from a clinical standpoint. Most neurosurgeons do not believe that SFTs can present as primary CNS neoplasms. Most SFTs are clinically benign and indolent, and recurrences after surgical excision are scarce. Because malignant transformation or metastasis has been reported, all SFTs should be treated as having malignant potential. Long-term follow-up is recommended. We report two cases, so that surgeons may recognize that this is an entity different from other spindle-cell CNS tumors.

Malignant Solitary Fibrous Tumor Metastatic to the Orbit

A 61-year-old man with a history of malignant solitary fibrous tumor of the chest had development of unusual sites of metastasis involving the sphenoid wing of the orbit and soft tissues of the cheek. He was found to have a solitary fibrous tumor, an uncommon type of spindle cell neoplasm that most often arises in the pleura, which was metastatic to the orbit. This is the first reported case of malignant solitary fibrous tumor metastatic to the orbit. The clinical and histopathologic findings of metastatic malignant solitary fibrous tumor are described.

Extrapleural benign solitary fibrous tumor in the shoulder of a 9-year-old girl: case report and review of the literature

We report a case of a benign solitary fibrous tumor that occurred in the right shoulder of a 9-year-old girl. This case is remarkable due to the unusual location of its occurrence and the young age of the patient. In addition, cytogenetic analysis revealed a karyotype unreported in this neoplasm: 46,XX,der(4)t(4;9)(q31.1;q34), del(9)(p22p24),der(9)t(4;9)(q31.1;q34)ins(9;?)(q34;?) (17 cells)/46,XX (3 cells).

Solitary fibrous tumor of the orbit--two cases and a review of the literature

Solitary fibrous tumors of the orbit (SFT) are mesenchymal lesions that can develop either as malignant or benign neoplasias. We describe the histological features leading to the diagnosis in two females and review the current literature. Diagnosis of SFT only can be performed by histological examination, since clinical signs and radiological features are not specific enough. Even a malignant or benign course cannot be predicted, since clinical and radiological features do not correlate with histological signs of malignancy and vice versa. Radical resection is the treatment of choice, since no other treatment option has been proven to be efficient.

Metastatic malignant solitary fibrous tumour to the infra-temporal fossa

Malignant solitary fibrous tumours (MSFTs) are rare tumours of fibrous origin, which can occur at all anatomical sites and represent 20% of solitary fibrous tumours. Fine-needle aspiration cytology is not able to distinguish benign from malignant disease, and sufficient tissue has to be obtained for accurate histological diagnosis to be made. Lesions > 10 cm in diameter and incomplete resection or non-resectability are predictive factors for poor long-term survival. We present a 57-year-old patient with a presumably metastatic MSFT from the peritoneal cavity to the skull-base who is in a stable state 17 months after surgical debulking of the skull-base and removal of the peritoneal lesion, followed by post-operative chemotherapy. We suggest the terminology metastatic malignant solitary fibrous tumour for a description of this disease.

Solitary fibrous tumor of the orbit: a clinicopathologic study of six cases with review of the literature

Solitary fibrous tumor of the orbit is a rare spindle cell neoplasm. There are 42 cases of solitary fibrous tumor of the orbit available in the literature. We present six more cases of orbital solitary fibrous tumors, which presented to our institute between 1999 and 2001. We highlight the need for clinical recognition of these tumors as a distinct entity and inclusion of this tumor in the etiological differential diagnosis of well-circumscribed orbital lesions presenting as unilateral proptosis in both children and in adults. The diagnosis may be suspected based on radiological features supported by histopathologic and immunohistochemical study. The strong CD34 immunoreactivity of this tumor supports its diagnosis. Complete surgical resection is the most important prognostic factor of this tumor.

Echography as a useful adjunct in the diagnosis of orbital solitary fibrous tumor

PURPOSE

To describe the echographic features of solitary fibrous tumor of the orbit.

METHODS

A retrospective review of 3 patients with solitary fibrous tumor of the orbit and a literature review were performed.

RESULTS

Three patients with orbital solitary fibrous tumor were studied with standardized echography and 3 other cases of orbital solitary fibrous tumor with ultrasound descriptions were identified in a literature review. Consistent echographic features of the 6 orbital solitary fibrous tumors included firmness, low to medium internal reflectivity, regular internal structure, moderate sound attenuation, and some degree of vascularity.

CONCLUSIONS

Standardized echography is a useful adjunct in the evaluation of orbital solitary fibrous tumors and can help differentiate these tumors from other orbital lesions.

Solitary fibrous tumor of the orbit

Painless unilateral proptosis is a frequent manifestation of numerous orbital neoplastic and non-neoplastic processes. Various mesenchymal tumors of both fibrohistiocytic and vascular origin are well-described causes. Solitary fibrous tumors (SFTs) are rare spindle-cell neoplasms usually found associated with serosal surfaces, especially the pleura, but they have recently been described in a number of extrapleural sites including the orbit. The authors describe the case of an 18-year-old man who presented with a 6-month history of painless proptosis in the right eye. A visible nontender mass in the right supermedial orbit producing ptosis of the upper lid was present. Magnetic resonance imaging (MRI) showed a well-circumscribed soft tissue mass located above the right globe with no obvious invasion of adjacent orbital structures. Uneventful surgical excision through a right frontal-orbitotomy approach was performed. Histological evaluation showed a solid, highly vascular tumor mass composed of spindle cells arranged in short ill-defined fascicles. Intense immunohistochemistry staining for CD34 and B-cell lymphoma 2 (BCL-2) differentiated the lesion from the more common hemangiopericytoma. Though considered benign, local recurrence and extraorbital extension of orbital SFTs have been described. Malignant behavior, including distant metastases, has been documented in as many as 20% of pleural cases with mortality rates as high as 50%. The natural history of this tumor in the orbit is unclear. The authors report the 35th case of orbital solitary fibrous tumor and discuss the differential diagnosis, histopathology, radiological features, and clinical course.