Clinicopathologic Features of Peripheral Nerve Sheath Tumors Involving the Eye and Ocular Adnexa

• Published in: Human pathology 2017-02, Vol.63, p.70-78
• Main Authors: Zhang, Mingjuan L., MD, Suarez, Maria J., MD, Bosley, Thomas M., MD, Rodriguez, Fausto J., MD
• Format: Article
• Language: English
• Subjects: Pathology
• ISSN: 0046-8177; 1532-8392
• DOI: 10.1016/j.humpath.2017.02.006

Summary 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 32.5 years. Locations included orbit (58.9%), eyelid (60.0%) and other ocular adnexa. A large majority of 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 peripheral nerve sheath tumor (n = 1). Fifty-six (88.9%) neurofibroma cases were neurofibromatosis 1 (NF1)-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 Ki67 (