Retrospective Evaluation of Canine Cutaneous Periocular Idiopathic Histiocytic Disease

To describe the clinical presentation, management, and histopathologic findings in dogs with cutaneous periocular histiocytic disease.

Retrospective review of 14 dogs (18 eyes) with cutaneous periocular histiocytic disease from January 2015 to January 2025. Follow-up data were obtained for 9 dogs (12 eyes). Variables evaluated included age, sex, breed, lesion location, characteristics and duration, histopathologic diagnosis, additional histopathologic staining or further testing performed, treatment, presence of other ocular/periocular disease, and recurrence of the mass after surgery.

The most prevalent lesion location was the lower eyelid followed by the lateral canthus. All of the lesions were interpreted as histiocyte-rich lesions with no identifiable underlying cause. Successful treatment for the 9 dogs (12 eyes) with follow-up was achieved by surgical excision alone in 2 dogs (2 eyes) and surgical excision with medical management in 7 dogs (10 eyes). Medical management included oral corticosteroids and/or other oral immunosuppressive drugs, subconjunctival corticosteroids, and topical immunomodulatory therapies. Of the nine dogs with follow up, only three dogs experienced lesion recurrence. Following medical management, none of the lesions had recurred in dogs with follow up at the final recheck exam.

Histiocytic lesions can affect the periocular tissues and should be included in differential diagnoses for mass lesions around the eyes. Recurrence is uncommon after surgical excision and lesions appear to respond to various immunomodulatory treatments.