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

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.

Brain Tumors Affecting the Orbit Globe and Orbit Tumors Affecting the Brain

Brain tumors affecting the orbit and orbital tumors affecting the brain are a heterogeneous group of lesions, with histological features, behaviors, diagnostic criteria, and treatments varying from each other. Dermoid cyst and cavernous hemangiomas are considered the most frequent benign lesions, while non-Hodgkin lymphoma is the most common malignant tumor in this region. Sharing the same anatomical region, clinical manifestations of orbital lesions may be often common to different types of lesions. Imaging studies are useful in the differential diagnosis of orbital lesions and the planning of their management. Lesions can be classified into ocular or extra-ocular ones: the latter can be further differentiated into extraconal or intraconal, based on the relationship with the extraocular muscles. Surgical therapy is the treatment of choice for most orbital lesions; however, based on the degree of removal, their histology and extension, other treatments, such as chemotherapy and radiotherapy, are indicated for the management of orbital lesions. In selected cases, chemotherapy and radiotherapy are the primary treatments. This chapter aimed to discuss the orbital anatomy, the clinical manifestations, the clinical testing and the imaging studies for orbital lesions, and the principal pathological entities affecting the orbit together with the principles of orbital surgery.

Malignant Solitary Fibrous Tumor of the Right Cerebellum: A Case Report

Solitary fibrous tumor is a very rare mesenchymal tumor that occurs mostly in the pleura, and there are few reported cases of a presence in the central nervous system, particularly in the cerebellum. In 2016, the WHO classified solitary fibrous tumors into grade I. In this article, we present a case of malignant solitary fibrous tumor recurring 8 years after surgery in a 63-year-old male. Magnetic resonance imaging showed low to intermediate mixed signal intensity on T1W1. Immunohistochemical staining positivity for Vimentin, CD99, CD34 and Bcl-2, it is consistent with the immunohistochemical characteristics of solitary fibrous tumor. We resected the patient's tumor, and the patient was followed up for 3 months with no signs of recurrence. Solitary fibrous tumors are very rare in the central nervous system. Immunohistochemical staining positivity for CD34 and Bcl-2 is strongly expressed in most solitary fibrous tumor. Surgical resection is the preferred treatment. Due to the small number of cases, the biological behavior and prognosis of this tumor need to be further explored.

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

PURPOSE

There is an imperfect correlation between the histology and behavior of solitary fibrous tumor (SFT). In addition, recurrence is common, and dedifferentiation may occur over time. Preferred primary treatment is intact excision, but friable pseudocapsules and tenacious attachments can thwart this goal in the crowded, visually sensitive orbit. This study addresses the fate and appropriate management of incompletely excised orbital SFT.

METHODS

Among a single surgeon's 7-case experience with orbital SFT, 3 cases involved incomplete primary excision, either before (2 cases) or after (1 case) referral. We reviewed the clinicopathologic data in these 3 cases, with follow-up intervals of 18, 21, and 52 years after initial presentation. We reviewed the English-language literature on SFT, with special attention to evolving nomenclature, orbital involvement, recurrence, malignant transformation, and management options.

RESULTS

Benign versus malignant designations of SFT vary with histological and behavioral criteria. Approximately 150 orbital cases have been reported. Published rates of primary malignancy and recurrence across all histologic categories are 6% to 12% and 30% to 37%, respectively. We identified 43 well-documented recurrences (range, 6 months-33 years; median, 3 years) and 10 cases of histological dedifferentiation (range, 14 months-33 years). Because of SFT's rarity and needed follow-up intervals, the value of adjuvant therapy is not yet proven. In follow up of 18, 21, and 52 years after initial presentation, our 3 cases with incomplete excision showed either no recurrence (Case 1) or no morphological dedifferentiation (Cases 2, 3).

CONCLUSION

A treatment algorithm is predicated on the completeness of surgical excision and histological features. However, we recommend case-by-case multidisciplinary decisions in a tumor-board setting.

Intracranial Solitary Fibrous Tumor of the Skull Base: 2 Cases and Systematic Review of the Literature

BACKGROUND

Intracranial solitary fibrous tumors (ISFTs) are rare neoplasms of mesenchymal origin that originate from the meninges. ISFTs of the skull base can be challenging to treat, as resection can be complicated by skull base anatomy. We present 2 cases of ISFT, the first manifesting with compressive cranial neuropathy from Meckel cave involvement and the second a posterior fossa lesion causing symptomatic hydrocephalus.

METHODS

A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The PubMed database was queried with title/abstract keywords "intracranial," "solitary fibrous tumor," "hemangiopericytoma," "SFT," and "HPC." Search results were reviewed to exclude cases not involving the skull base. References from all selected articles were reviewed for potential additional cases. Patient demographic and clinical data from 58 identified skull base cases were collected for qualitative synthesis.

RESULTS

Visual disturbances were the most common presenting symptom (30 cases, 52%) followed by headache (22 cases, 38%). The most common site of involvement was the sellar/parasellar region (18 cases, 31%) followed by middle fossa/temporal bone (14 cases, 24%). Resection was performed in 55 cases; gross total resection was reported in 26 cases (45%) and subtotal resection was reported in 21 cases (36%). Tumor recurrence was documented in 15 cases (26%) with median and mean follow-up periods of 16 and 29.9 months, respectively.

CONCLUSIONS

We discuss presentation, imaging, histopathology, and management considerations for ISFTs while highlighting the potentially complex nature of skull base lesions and need for multidisciplinary approach to treatment.

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.

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.

Intraorbital Solitary Fibrous Tumor Requiring Preoperative Embolization of Feeding Artery

Solitary fibrous tumors (SFTs) are derived from mesenchymal cells and commonly develop in thoracoabdominal organs; however, their occurrence in orbit is rare. The first-choice treatment is to surgically remove as much of the SFT as possible; however, if total removal is not achieved, the recurrence rate is high, resulting in poor prognosis. A 42-year-old man presented with painless right-sided proptosis and diplopia 4 years ago. Orbital computed tomography revealed a right extraconal mass medial to the optic nerve, measuring 25 mm. Magnetic resonance imaging demonstrated iso-signal intensity on T1- and T2-weighted imaging, including flow-void signals. During biopsy of the intraorbital mass, which was performed by ophthalmologists 3 years earlier, difficulty with hemostasis occurred due to massive hemorrhage from the mass. The mass grew to reach a maximal diameter of 33 mm, resulting in referral to the authors’ department. Diagnostic cerebral angiography revealed a hypervascular orbital tumor with multiple feeding arteries. To control intraoperative bleeding, the patient underwent preoperative endovascular embolization. Subsequently, the tumor was completely removed using a combination of microsurgical craniotomy and endoscopic endonasal approach, without the occurrence of massive intraoperative hemorrhage from the tumor. Postoperatively, his clinical course was uneventful except for the remaining preoperative diplopia. The tumor was diagnosed histologically as SFT and has not recurred for 8 months since surgery. Preoperative intravascular embolization of branches of the ophthalmic artery can be performed safely, resulting in excellent control of intraoperative bleeding and facilitating complete removal of SFT without additional complications.