REASONS FOR PERFORMING STUDY: Preputial and penile tumours are more common in horses than in other domestic animals, but no large surveys of male horses with tumours of the external genitalia are available. OBJECTIVE: To present a retrospective analysis of male horses with neoplasms of the external genitalia. METHODS: The penile and preputial tumours of 114 horses were evaluated. Data recorded included age, gelding or stallion and breed; type and site of lesion; involvement of regional lymph nodes; histopathology (including grading of squamous cell carcinoma); and results of radiographic examination of the thorax. RESULTS: Mean age of horses was 19.5 years with no apparent breed predilection. Common presenting clinical signs were irregularities (e.g. the presence of a mass and/or ulceration) on the integument of the penis and prepuce, and purulent or sanguineous discharge from preputial orifice. Squamous cell carcinoma (SCC) was the most prevalent neoplasm followed by papillomas and melanomas. A basal cell carcinoma, neurofibrosarcoma, adenocarcinoma or fibrosarcoma were each found on single horses. Squamous cell carcinomas with poor differentiation had a higher tendency to metastasise than did more differentiated tumours. CONCLUSIONS: Squamous cell carcinoma is the most common urogenital tumour of the male horse and occurs primarily in old horses. Horses with poorly differentiated SCCs tend to have a higher incidence of regional metastases. Pathology of lymph nodes, even when not palpably enlarged, is a valuable diagnostic exercise. Radiology of the thorax to detect lung metastases is of little value.
REASONS FOR PERFORMING STUDY: Preputial and penile tumours are more common in horses than in other domestic animals, but no large surveys of male horses with tumours of the external genitalia are available. OBJECTIVE: To present a retrospective analysis of male horses with neoplasms of the external genitalia. METHODS: The penile and preputial tumours of 114 horses were evaluated. Data recorded included age, gelding or stallion and breed; type and site of lesion; involvement of regional lymph nodes; histopathology (including grading of squamous cell carcinoma); and results of radiographic examination of the thorax. RESULTS: Mean age of horses was 19.5 years with no apparent breed predilection. Common presenting clinical signs were irregularities (e.g. the presence of a mass and/or ulceration) on the integument of the penis and prepuce, and purulent or sanguineous discharge from preputial orifice. Squamous cell carcinoma (SCC) was the most prevalent neoplasm followed by papillomas and melanomas. A basal cell carcinoma, neurofibrosarcoma, adenocarcinoma or fibrosarcoma were each found on single horses. Squamous cell carcinomas with poor differentiation had a higher tendency to metastasise than did more differentiated tumours. CONCLUSIONS:Squamous cell carcinoma is the most common urogenital tumour of the male horse and occurs primarily in old horses. Horses with poorly differentiated SCCs tend to have a higher incidence of regional metastases. Pathology of lymph nodes, even when not palpably enlarged, is a valuable diagnostic exercise. Radiology of the thorax to detect lung metastases is of little value.
Authors: Moriel H Singer-Berk; Kelly E Knickelbein; Zachary T Lounsberry; Margo Crausaz; Savanna Vig; Nikhil Joshi; Monica Britton; Matthew L Settles; Christopher M Reilly; Ellison Bentley; Catherine Nunnery; Ann Dwyer; Mary E Lassaline; Rebecca R Bellone Journal: Int J Genomics Date: 2019-09-15 Impact factor: 2.326
Authors: Anna Sophie Ramsauer; Garrett Louis Wachoski-Dark; Cornel Fraefel; Kurt Tobler; Sabine Brandt; Cameron Greig Knight; Claude Favrot; Paula Grest Journal: BMC Vet Res Date: 2019-10-22 Impact factor: 2.741
Authors: Lucia Unger; Carlos Abril; Vinzenz Gerber; Vidhya Jagannathan; Christoph Koch; Eman Hamza Journal: J Vet Intern Med Date: 2021-01-07 Impact factor: 3.175