[A case of intraorbital solitary fibrous tumor resected successfully with preoperative arterial embolization]

Solitary fibrous tumour of lacrimal sac masquerading as lacrimal sac mucocele: a diagnostic and surgical dilemma

Swellings in medial canthal area in eye most often involve the lacrimal sac, the commonest aetiology being chronic dacryocystitis. Very rarely, there is a deviation in the routine diagnosis when the pathology comes out to be a lacrimal sac tumour. We report the case of a young man who presented with a medial canthal mass not extending above the medial canthal ligament. The clinical presentation was typical for a lacrimal sac mucocele, however on histopathological evaluation was diagnosed as a rare case of solitary fibrous tumour of lacrimal sac. We recommend radiological investigation in medial canthal masses where there is negative regurgitation on pressure over lacrimal sac area to avoid misdiagnoses.

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.

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.