Aryepiglottic lymphoma in a 19-year-old Paint gelding treated with excision and adjunctive radiotherapy

This case report describes the diagnosis and treatment of an aryepiglottic tumour in a 19-year-old Paint gelding. Diagnostic work-up included physical examination, endoscopic evaluation of the upper airway, and histopathology of the mass following removal. Treatment consisted of surgical excision of the aryepiglottic mass under endoscopic guidance followed by a 100 Gy dose of radiation delivered with strontium-90 plesiotherapy to the surgical bed at 72 h post-operatively. The radiation applicator was passed through the left nostril and the application area was confirmed via endoscopic evaluation. Histopathology, including immunohistochemistry, confirmed that the aryepiglottic tumour was T cell lymphoma. Recheck examination, including physical examination and upper airway endoscopy, was performed 1, 3 and 6 months following treatment and local recurrence was not observed. Local control with minimal morbidity can be achieved with surgical excision of equine lymphoma followed by strontium-90 plesiotherapy.