Primary intraocular ancient schwannoma: a case report and review of the literature

Orbital schwannoma arising within inferior rectus muscle: A rare orbital tumor

Purpose

To report a rare orbital schwannoma arising within inferior rectus muscle in a young woman.

Observations

In this case report, we describe a young patient with slowly progressive proptosis for one year. Preoperative imaging was suggestive of a benign tumor arising within inferior rectus muscle, and histopathologic evaluation revealed an orbital schwannoma with cystic degeneration.

Conclusion and importance

This case report highlights the importance of including schwannoma in the differential diagnosis of any orbital tumor arising within muscle.

Intraocular schwannoma: case series of 28 patients and literature review

PURPOSE

Intraocular schwannoma is a rare tumour, which is often misdiagnosed. We presented the demographics and clinical characteristics of patients with intraocular schwannoma.

METHODS

Retrospective case series were collected between May 2005 and July 2021 in Beijing Tongren Hospital.

RESULTS

A total of 28 patients were diagnosed with intraocular schwannoma on histopathological examination of surgical specimen. The median age was 39 years (range: 12-64). Fourteen patients were female and 14 were male. Among the all subjects, 21/28 patients (75.0%) presented as visual loss, and 3/28 patients (10.7%) had visual field loss. Intraocular schwannoma presented as nonpigmented mass in the ciliary body in 12/28 cases (42.9%), in the choroid in 9/28 cases (32.1%), and in ciliochoroid in 7/28 cases (25.0%). Intraocular schwannoma was often clinically misdiagnosed as uveal melanoma, which occurred in 16/28 patients (57.1%). Tumour excision with pars plana vitrectomy was performed for all included patients. Endoresection with lens removal was performed for tumours in the choroid, while transscleral resection was performed for tumours located in ciliary body or ciliochoroid. Increased light transmission was detected in 12/28 cases (42.9%). In the consecutive follow-up (median: 73 months, range: 7-193 months), no cases of recurrence or metastatic disease were detected.

CONCLUSIONS

Intraocular schwannoma is a rare benign tumour. It usually presents as nonpigmented mass, which can easily be misdiagnosed as nonpigmented uveal melanoma.

Pediatric dumbbell-shaped orbital schwannoma with extension to the cranial cavity: A case report and literature review

Orbital schwannomas are rare in children, especially those with intracranial extension. Herein, our report refers to a 12-year-old boy who had a cranial-orbital mass with a dumbbell-like appearance. The total neoplasms was successfully removed via a transcranial approach, and the pathological diagnostic result was schwannoma. Neither radiotherapy nor chemotherapy was performed after surgery, and no recurrences were observed for 3 months. Our report suggests that orbital schwannomas should be differentiated from other types of orbital tumors with sufficient evidence and that complete surgical resection remains the first choice to cure this disease.

Orbital schwannoma management: a case report, literature review, and potential paradigm shift

PURPOSE

To present a case of orbital schwannoma and assess the literature on treatment modalities.

METHODS

A MEDLINE literature search for cases of orbital schwannomas was performed using the PubMed search tool using the search terms "orbital schwannoma" and "orbital neurilemmoma." Papers were included if they were peer-reviewed, published in English, discussed management, and included the search terms. Each article was rated using the scale developed by the British Centre for Evidence-Based Medicine. In addition, we present a case report of an orbital schwannoma.

RESULTS

A total of 428 articles were found. 102 met the criteria for inclusion. Only two articles met Level 1 evidence and 16 were important to the clinical care process. We report a case of a biopsy-proven orbital schwannoma managed conservatively with observation over a 4-year period due to risk of cosmetic disfigurement with tumor removal. There has been no change in tumor size and no associated complications during follow up.

CONCLUSIONS

There is a paucity of data on the natural history of orbital schwannomas. Based on our review of the literature, we recommend observation for asymptomatic or minimally symptomatic orbital schwannomas with minimal growth over an extended period of time. For rapidly growing tumors or large tumors affecting key structures causing visual loss, diplopia, aesthetic disfigurement, or patient discomfort, a more aggressive approach may be necessary.

Intraocular schwannoma with extrascleral extension

PURPOSE

To report a rare case of intraocular schwannoma with extrascleral extension in a patient with juvenile idiopathic arthritis and to review the literature for this topic.

METHODS

Case report.

RESULTS

A 19-year-old male with a history of juvenile idiopathic arthritis was referred for diagnosis and management of an episcleral mass, initially thought to be focal nodular scleritis. The ocular surface of the right eye revealed an elevated amelanotic episcleral nodule inferonasally, with thin strands of overlying sclera, feeding episcleral vessels, and measuring 11 mm × 11 mm in diameter and 5 mm in thickness. Ophthalmoscopic examination revealed a minimally pigmented ciliochoroidal tumor measuring 13 mm in diameter and 11.4 mm in total thickness and without associated subretinal fluid, orange pigment, or drusen. Ultrasound biomicroscopy and anterior-segment optical coherence tomography confirmed a solid mass with scleral disruption and extraocular extension. Shave biopsy revealed palisading spindle cells and interspersed eosinophilic fibrillary cytoplasmic processes, forming Verocay bodies. The specimen stained positive for S-100 and negative for Melan-A, consistent with benign schwannoma. Observation was recommended.

CONCLUSION

Intraocular schwannoma is a rare, benign uveal tumor that can demonstrate extrascleral extension, mimicking inflammatory and malignant neoplastic processes. Clinical diagnosis is challenging, and tissue biopsy is required for definite diagnosis.

Intraocular schwannoma: A case series of 3 patients

Schwannoma is a proliferation of neoplastic Schwann cells. Schwannomas comprise 8-10% of all primary intracranial tumors. Primary intraorbital schwannoma arising from the ciliary nerves in the uvea, which accounts for 1-2% of all intracranial tumors, is a rare intraocular neoplasm. Intraocular schwannoma frequently masquerades as melanoma, reflecting the difficulty in clinically distinguishing it from malignant melanoma and the requirement for a histopathological diagnosis. The aim of the present study was to report a case series of 3 patients diagnosed with intraocular schwannoma at the Department of Ophthalmology, Peking University People's Hospital (Beijing, China). Patients with intraocular schwannoma were identified by searching the computerized database and patient medical records of the Department of Ophthalmology of Peking University People's Hospital. The patients (2 men and 1 woman; mean age, 34 years; age range, 25-48 years) were all treated by trans-scleral local resection, and schwannoma was confirmed by biopsy. The study found that choroidal schwannoma has a variety of clinical manifestations, with iridodialysis, subluxation of the lens and exudative detachment of the retina observed. The present study indicates that a pathological biopsy is required for diagnosis and that the optimal therapy is local resection.

Clinicopathological features of peripheral nerve sheath tumors involving the eye and ocular adnexa

Peripheral nerve sheath tumors (PNSTs) are known to occur in the orbit and comprise 4% of all orbital tumors, but have not been well studied in contemporary literature. Ninety specimens involving the eye and ocular adnexa (1979-2015) from 67 patients were studied. The mean age was 32.5years. Locations included orbit (58.9%), eyelid (60.0%), and other ocular adnexa. Most specimens were neurofibromas (70.0%), followed by schwannomas (11.1%), neuromas (11.1%), granular cell tumors (n=4), nerve sheath myxomas (n=2), and malignant PNST (n=1). Fifty-six (88.9%) neurofibroma cases were neurofibromatosis 1 associated. Among neurofibromas, 31.7% were localized, 38.1% were plexiform, 25.4% were diffuse, and 4.8% were diffuse and plexiform. These tumors involved skin (31.7%), soft tissue (11.1%), skeletal muscle (22.2%), peripheral nerve (63.0%), lacrimal gland (20.6%), and choroid (n=1). Other histologic findings included pseudo-Meissner corpuscles (27%), Schwann cell nodules (4.8%), prominent myxoid component (7.9%), melanin-like pigment (3.2%), and inflammation (14.3%). Available immunostains included S100 (+ in 15/15 cases), EMA (+ in 2/4 cases), CD34 (+ in 4/4 cases), and Ki-67 (<1% in 4/4 cases). Among 10 schwannomas, 8 were conventional and 2 were plexiform. Observed features included capsule (n=5), hyalinized vessels (n=5), Verocay bodies (n=7), and Antoni B pattern (n=5). Immunostaining included S100+ in 4 of 4 cases, and collagen IV+ and Ki-67 <1% in 3 of 3 cases. Neurofibromas are the most common PNST involving the eye and ocular adnexa, and the majority are associated with neurofibromatosis 1. Plexiform and diffuse patterns and the presence of pseudo-Meissner corpuscles are relatively frequent in this area.