Fate and Management of Incompletely Excised Solitary Fibrous Tumor of the Orbit: A Case Series and Literature Review

Case Report of Rare Solitary Fibrous Tumour of Nape of Neck with Review of Literature

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor with an indolent course but variable metastatic potential. Less than 50 cases of neck SFTs have been documented since 1991. We present a case report of rare presentations of SFT of nape of neck typifying the hypercellular variant of SFT (hemangiopericytoma) with challenges in treatment. Patient underwent excision and was subjected to adjuvant radiation. We concluded that SFT though a rare diagnosis should be considered while dealing with soft tissue tumors and multi-disciplinary pre-operative planning is must to avoid complications and recurrence. Surgical excision remains treatment of choice, but long follow-up is must.

MR Imaging Characteristics of Solitary Fibrous Tumors of the Orbit : Case Series of 18 Patients

PURPOSE

Solitary fibrous tumor (SFT) of the orbit is a rare tumor that was first described in 1994. We aimed to investigate its imaging characteristics that may facilitate the differential diagnosis between SFT and other types of orbital tumors.

MATERIAL AND METHODS

Magnetic resonance imaging (MRI) data of patients with immunohistochemically confirmed orbital SFT from 2002 to 2022 at a tertiary care center were retrospectively analyzed. Tumor location, size, morphological characteristics, and contrast enhancement features were evaluated.

RESULTS

Of the 18 eligible patients 10 were female (56%) with a mean age of 52 years. Most of the SFTs were oval-shaped (67%) with a sharp margin (83%). The most frequent locations were the laterocranial quadrant (44%), the extraconal space (67%) and the dorsal half of the orbit (67%). A flow void phenomenon was observed in nearly all cases (94%). On the T1-weighted imaging, tumor signal intensity (SI) was significantly lower than that of the retrobulbar fat and appeared predominantly equivalent (82%) to the temporomesial brain cortex, while on T2-weighted imaging its SI remained equivalent (50%) or slightly hyperintense to that of brain cortex. More than half of the lesions showed a homogeneous contrast enhancement pattern with a median SI increase of 2.2-fold compared to baseline precontrast imaging.

CONCLUSION

The SFT represents a rare orbital tumor with several characteristic imaging features. It was mostly oval-shaped with a sharp margin and frequently localized in the extraconal space and dorsal half of the orbit. Flow voids indicating hypervascularization were the most common findings.

Prevalence of TERT Promoter Mutations in Orbital Solitary Fibrous Tumors

The orbital manifestation of a solitary fibrous tumor (SFT) is exceptionally rare and poses specific challenges in diagnosis and treatment. Its rather exceptional behavior among all SFTs comprises a high tendency towards local recurrence, but it rarely culminates in metastatic disease. This raises the question of prognostic factors in orbital SFTs (oSFTs). Telomerase reverse transcriptase (TERT)-promoter mutations have previously been linked to an unfavorable prognosis in SFTs of other locations. We analyzed the prevalence of TERT promoter mutations of SFTs in the orbital compartment. We performed a retrospective, descriptive clinico-histopathological analysis of nine cases of oSFTs between the years of 2017 and 2021. A TERT promoter mutation was present in one case, which was classified with intermediate metastatic risk. Local recurrence or progress occurred in six cases after primary resection; no distant metastases were reported. Multimodal imaging repeatedly showed particular morphologic patterns, including tubular vascular structures and ADC reduction. The prevalence of the TERT promoter mutation in oSFT was 11%, which is similar to the prevalence of extra-meningeal SFTs of the head and neck and lower than that in other extra-meningeal compartments. In the present study, the TERT promoter mutation in oSFT manifested in a case with an unfavorable prognosis, comprising aggressive local tumor growth, local recurrence, and eye loss.

Radiologic Features of Well-circumscribed Orbital Tumors With Histopathologic Correlation: A Multi-center Study

PURPOSE

To delineate specific imaging characteristics of solitary fibrous tumors, schwannomas, cavernous venous malformations, and well-circumscribed orbital lymphoma.

METHODS

Patients undergoing excisional biopsy of solitary fibrous tumor, schwannomas, cavernous venous malformations, or well-circumscribed orbital lymphoma with preoperative MRIs available for review were identified at 3 academic centers in the United States and Australia. An exploratory statistical analysis was performed to identify important radiologic features, which were subsequently included in a random forest model. Histopathologic correlates were evaluated in representative cases.

RESULTS

A total of 91 cases were included with a mean age of 52.9 ± 17.2 years. Nearly all solitary fibrous tumors were located in the anterior or mid orbit (87.5%) and they more commonly demonstrated intralesional heterogeneity on T2-weighted imaging (45.5%) (p < 0.01). Compared with the other tumors, schwannomas tended to be intraconal (66.7%) and were often in the mid or posterior orbit (83.4%) (p < 0.01). Cavernous venous malformations characteristically demonstrated progressive contrast enhancement (93.9%; p < 0.01). Most lesions in all 4 groups were hypointense on T1-weighted imaging (80%-100%; p = 0.14) and only well-circumscribed orbital lymphoma tended to also be hypointense on T2 (81.8%) (p < 0.01). Finally, cases of lymphoma had significantly lower apparent diffusion coefficient ratios (0.9 ± 0.2) (p < 0.001), while the other 3 groups were not significantly different from one another (cavernous venous malformations: 1.8 ± 0.4; schwannomas: 1.8 ± 0.5; and solitary fibrous tumor: 1.6 ± 0.6) (p = 0.739).

CONCLUSIONS

Key features that aid in the differentiation of these 4 tumors from one another include T2 intensity and homogeneity, early contrast-enhancement pattern, and ADC ratio.

Long-Term Surgical Outcome for Orbital Solitary Fibrous Tumors

PURPOSE

To report long-term outcomes after surgery for orbital solitary fibrous tumors.

METHODS

Retrospective review of patients with orbital solitary fibrous tumor, first seen between 1971 and 2022. Primary excisions were grouped as (A) surgically intact, (B) macroscopic, but with cell spillage, or (C) known incomplete excision.

RESULTS

Fifty-nine patients (31 female; 53%) presented at a mean age of 43.0 years (19-82 years), with 5 patients (8.5%) having malignant solitary fibrous tumors. Average follow up was 11.4 years (median 7.8; range 1-43 years). There were 28 of 59 (47%) group A patients with 1 of 28 (3%) having recurrence, 20 of 59 (34%) group B having 6 of 20 (30%) recurrences, and 11 of 59 (19%) group C with 9 of 11 (82%) recurrence ( p < 0.001 for recurrence rate). At a mean of 8.9 (range 1-23.6) years after initial treatment, continued local tumor growth was evident in 16 (27%) patients, with higher-grade recurrence in 3 of 14 (21%) cases. No patient had systemic disease at presentation, but 2 of 59 patients (3%) developed metastases at 22 and 30 years after first treatment. The 10-year progression-free survival was 94% (group A), 60% (group B), and 36% (group C). Tumor disruption or incomplete excision (groups B + C) carries the highest risk of tumor recurrence (hazard ratio 15.0; 95% confidence interval, 1.98-114; p = 0.009), with no correlation to tumor size or histology.

CONCLUSIONS

Orbital solitary fibrous tumors have a low recurrence rate with surgically intact excision; piecemeal excision, capsular disruption, or known incomplete resection have a high recurrence rate, which can occur decades later. Baseline postoperative scans is recommended, together with long-term clinical and interval imaging.

Malignant recurrent orbital solitary fibrous tumor

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor of fibroblastic origin commonly occurring in pleura. It can occur at many extrapleural sites but is rare in orbit. Most cases are benign and recurrence is not unusual in the head and neck and orbit and is usually due to incomplete surgical excision. However, malignant transformation (MT) in orbital SFT is extremely unusual. We present a case of orbital SFT in adult male who developed recurrence with MT eight years after initial surgical excision. He underwent left orbital exenteration. The recurrent tumor revealed features of malignancy with areas exhibiting morphology typical of SFT. The immunochemistry confirmed the diagnosis of SFT with MT. The patient was given adjuvant radiation and was disease free for the last 18 months. Identification of malignancy in orbital SFT is important for the patient to receive appropriate postoperative treatment, as seen in the present case.

Multiple CD34-Negative Orbital Solitary Fibrous Tumors in a Pediatric Patient

A 12-year-old Japanese male presented with a 2-month history of headache that was later on associated with diplopia, painless proptosis of the OS, and left ophthalmoplegia. Initial examination revealed a 7-mm OS protrusion, which worsened to 9 mm in less than a month. Preoperative visual acuity worsened from 1.0 to 0.2 with the development of left afferent pupillary defect. Left ocular motility was severely restricted in all directions. Magnetic resonance imaging showed two well-defined lesions adjacent to one another in the left orbit. The patient underwent surgical excision of the left orbital masses. Histopathology findings were consistent with solitary fibrous tumor of the orbit. Immunohistochemistry findings revealed CD34-negative but signal transducer and activator of transcription 6-positive for both specimens. The patient was monitored postoperatively and there was no recurrence of the tumor even after 6 months.

A review of solitary fibrous tumours of the orbit and ocular adnexa

Solitary fibrous tumour (SFT) is an uncommon spindle cell tumour of mesenchymal origin characterised by NAB2-STAT6 gene fusion. Although it was first described in the pleura, it can occur in connective tissue in any part of the body, but rarely presents in the orbit and ocular adnexa. SFT, which is part of the same disease spectrum as other fibroblastic tumours such as giant cell angiofibroma, haemangiopericytoma and fibrous histiocytoma, usually presents as a painless, slow-growing mass in any age group and generally follows a benign course, with a good prognosis after complete excision. However, malignant forms rarely occur. Even for benign tumours a more aggressive clinical behaviour is possible, with relentless infiltrative local growth, frequent recurrence following surgery, and malignant transformation with the potential for metastatic spread. Careful long-term follow-up is essential. The published literature on SFTs of the orbit and ocular adnexa is reviewed, and the aetiology, clinical presentation, epidemiology, radiological features, histopathology, immunohistochemistry, risk stratification, clinical management, and prognosis are discussed, reflecting on our own experience.

Bilobed flap reconstruction after en-bloc removal of solitary fibrous tumor of the lacrimal sac

Purpose

To report a rare case of a solitary fibrous tumor (SFT) of the lacrimal sac and discuss considerations for management of similar cases.

Observations

We present the case of a 41-year-old woman who presented with a primary lacrimal sac SFT for which she underwent en-bloc surgical resection. We discuss management options for SFTs and our surgical approach for this case: bilobed flap reconstruction of the medial canthus and inferior orbit.

Conclusions

We present an uncommon presentation of a rare tumor and a successful one-stage reconstruction with a bilobed flap.

Orbital solitary fibrous tumours: clinicopathological characteristics and recurrence prediction

BACKGROUND

SFTs are thought to have an unpredictable clinical course and currently have no recognized prognostic criterion. Our study aimed to determine the relationship between clinicopathological characteristics and the prognosis of patients with orbital SFTs.

METHODS

The clinicopathological features of these patients were extracted from clinical records. The relationships between these features and prognosis were analysed.

RESULTS

The positive rates of CD34, CD99, Blc2, and STAT6 expression were 90.3%, 90.3%, 83.9%, and 100%, respectively. The tumour recurrence rate was 38.7%. A higher recurrence rate was observed in patients with Ki67 index ≥ 5 (56.25% vs. 20%, P = 0.038).

CONCLUSION

A Ki67 index ≥ 5 was an effective parameter for predicting tumour recurrence of orbital SFTs. Close follow-up is needed for these patients.

Solitary Fibrous Tumors of the Head and Neck: A Single-Institution Study of 52 Patients

Objective

To evaluate the clinicopathologic characteristics of head and neck solitary fibrous tumors and features that may predict tumor recurrence.

Study Design

Retrospective review.

Setting

University of California–Los Angeles Medical Center.

Methods

A single-center retrospective study was conducted on pathologically confirmed cases of head and neck solitary fibrous tumors between 1996 and 2021. Patient demographics, clinical course, and histopathologic features were evaluated. Recurrence-free survival was estimated via Kaplan-Meier analysis.

Results

A total of 52 patients were reviewed. The average patient age was 54.7 years (range, 15-89). The most common subsite was the orbit (53.8%, n = 28), but other involved areas included the nasopharynx, paranasal sinuses, and scalp. The median tumor size was 2.95 cm (range, 1.3-11.2). Strong STAT6 (100%) and CD34 (97.9%) expression was observed on immunohistochemistry. Almost all patients were initially managed with wide local excision; 82% of patients (n = 14) had positive margins on pathologic review; and 15% (n = 4) had recurrence at a median 28.5 months (range, 10-113). White patient race was the only significant predictor of tumor recurrence. Patient age (≥55 years), tumor size (≥4), high mitotic rate, and disease subsite were not associated with recurrence.

Conclusion

Head and neck solitary fibrous tumors demonstrate a significantly larger local recurrence rate as compared with their rate of metastasis. They can recur many years following initial therapy, warranting long-term surveillance and follow-up to assess for tumor recurrence.

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.

Solitary Fibrous Tumor of the Orbit: A Clinicopathologic Study of Two Cases With Review of the Literature

BACKGROUND/AIM

Orbital solitary fibrous tumor (SFT) is a rare lesion among orbital tumors, which can be misdiagnosed as another mesenchymal tumor. In this study we report two cases of orbital SFT, focusing on the imaging and pathological findings of the vascular structure inside the tumor.

CASE REPORT

A 26-year-old woman and 43-year-old man presented with orbital SFT. The pathological findings revealed a patternless growth pattern of the tumor cells and hemangiopericytoma-like vascularity as well as thickened, dilated blood vessels within the tumor tissue. Tumor cells revealed a diffuse strong positivity for cluster of differentiation 34 (CD34) and signal transducer and activator of transcription 6 (STAT6) in both cases, while B-cell lymphoma 2 (bcl-2) and CD99 were positive in one case. Characteristic findings within the tumor were the arterial components, where a variety of STAT6, CD99 and bcl-2-positive smooth muscle cells were intermingled.

CONCLUSION

Histologically, the tumor tissues might be characterized by not only conventional hemangiopericytoma-like vasculature but also dilated arterial vessels, which were shown to be part of the tumor components.

Factors for postoperative recurrence of orbital solitary fibrous tumor: an analysis of long-term clinical follow-up results from a Chinese tertiary hospital

BACKGROUND

This study analyzed the clinical features, imaging manifestations, histopathology, immunohistochemistry, and surgical approaches of the orbital solitary fibrous tumor (OSFT), as well as the factors for postoperative recurrence of such disease.

METHODS

The clinical data of 16 patients with OSFT treated in our center from 2003 to 2020 were analyzed retrospectively, and the clinical symptoms, treatment methods, and follow-up results were recorded.

RESULTS

Of the 16 patients, 8 were females (50.0 %) and 8 were males (50.0 %); the average age of treatment was 37 ± 7 years and the median follow-up time was 74 (8, 228) months. Sixteen patients with OSFT underwent a total of 29 operations, of which 12 were transorbital approach operations and 17 were transfronto-orbital approach operations. Ten patients (10/16, 62.5 %) had recurrence. The recurrence rate of transorbital approach operations was 83.3 % (10/12), and the recurrence rate of transfronto-orbital approach operations was 17.6 % (3/17). No patients had treatment-related complications.

CONCLUSIONS

The main pathological feature of OSFT is a benign tumor. OSFT has a tendency to grow toward the cranio-orbital junction. The postoperative recurrence rate of OSFT is relatively high, so complete tumor resection is very important for prognosis. Inappropriate surgical approaches can lead to incomplete removal of the tumor and cause recurrence. Choosing the correct operation approach according to the position of the OSFT in the orbit and complete removal of the dura mater and bone affected by the tumor is crucial for the prognosis. Nevertheless, regular long-term follow-up after complete resection is necessary.