An update on penile neoplasia in horses

Abstract

Tumors at the level of the penis can cause severe discomfort in the horse but can also metastasize and be lethal. Several types of neoplasia have been documented but squamous cell carcinoma is the most prevalent. As the penis is mostly hidden inside the prepuce, these tumors are often only acknowledged in a more severe stage, which can require a more radical treatment. Beside cryotherapy, chemotherapy and COX-inhibitors as non-surgical treatments, local excision is often performed either as segmental posthectomy, partial phallectomy or en bloc resection of the penis and prepuce. Treatment and prognosis depend on the type, size, location, local invasiveness and presence of tumor metastasis. The aim of this article is to provide a brief overview of the etiology, diagnosis, treatment and prognosis of penile neoplasia in the horse.