Ciliary body myxoid epithelioid sarcoma in a cat: a case report

• Published in: BMC veterinary research Vol. 20; no. 1; pp. 442 - 5
• Main Authors: Leis, Marina L, Sayi, Soraya, Grahn, Bruce H
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 01.10.2024; BioMed Central; BMC
• Subjects: Animals; Case Report; Cat; Cat Diseases - diagnosis; Cat Diseases - pathology; Cat Diseases - surgery; Cats; Ciliary body; Ciliary Body - pathology; Ciliary body tumor; Diagnosis; Diseases; Female; Glaucoma; Health aspects; Keratin; Melanoma; Myxoid sarcoma; Myxosarcoma - diagnosis; Myxosarcoma - pathology; Myxosarcoma - veterinary; Non-Hodgkin's lymphomas; Sarcoma; Sarcoma - diagnosis; Sarcoma - pathology; Sarcoma - veterinary; Uveal Neoplasms - diagnosis; Uveal Neoplasms - pathology; Uveal Neoplasms - veterinary; Canada; Myxoid sarcoma; Cat; Ciliary body tumor
• ISSN: 1746-6148; 1746-6148
• DOI: 10.1186/s12917-024-04286-3

The majority of primary, intraocular tumors in cats originate from the uvea and include feline diffuse iris melanoma, lymphoma, and iridociliary epithelial adenoma or adenocarcinoma. In this case report, we describe for the first time the clinical, histological, and immunohistochemical findings of a rare myxoid intraocular neoplasm arising from the ciliary body in a cat. A 14-year-old, female, spayed domestic shorthaired cat was presented for evaluation of discolouration of the right eye. Upon examination, a clear to light whitish-tan, bubble-shaped intraocular mass adherent to the inferior ciliary body and extending into the anterior chamber was noted. Within five weeks, the tumor was significantly larger and the eye had developed secondary glaucoma so was enucleated. Light microscopic examination of the globe revealed a multinodular, hypocellular neoplasm arising from the ciliary body composed of interwoven spindle cells embedded in abundant amounts of a lightly basophilic myxoid matrix. Neoplastic cells exhibited strong immunoreactivity for cytokeratin while also showing moderate to strong immunoreactivity to vimentin. A diagnosis was therefore made of an unusual intraocular myxoid epithelioid sarcoma arising from the ciliary body. Although apparently exceedingly rare, epithelioid myxosarcoma should be included as a differential diagnosis for intraocular tumors in cats and they represent a clinical, histologic, and immunohistochemical diagnostic challenge. Early surgical intervention should be considered to prevent local invasion and ascension to the brain.