Optic nerve sheath solitary fibrous tumor

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.

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.

[Solitary fibrous tumor of the orbit: Possibly recurrent in the long-run]

Solitary fibrous tumor (SFT) is a rare etiology of progressive unilateral exophthalmia. The tumor is of mesenchymal origin and it is usually well defined. But recurrences can occur despite of complete surgical resection. Metastases have been observed. Tumors of the SFT spectrum are considered as benign or low-grade malignant. Histological features do not currently allow any prognosis. The most important prognostic factor is complete surgical resection. Craniofacial approaches provide a good view of the tumor extensions and orbital contents. Recurrent tumors must be surgically removed when possible. Complementary treatments have not proved effective. A very long-term follow-up is mandatory.