Abstract: To describe the clinical appearance, histopathology, and treatment of equine intraocular melanocytic neoplasia in adult horses. Unassigned: A retrospective review of medical records was conducted. Data recorded included signalment, ocular examination findings, physical examination findings, therapeutic interventions, and case outcomes. Histopathologic characteristics of enucleated globes were evaluated. A Student's -test was used to evaluate differences in the interval from diagnosis to last known outcome between horses receiving therapeutic interventions and horses undergoing monitoring alone. Unassigned: Of the 55 horses included, Arabian was the most common breed (15/55, 27%). Gray was the most common coat color (85%). Physical examination was completed for 75% of horses at time of diagnosis, and of those, 67% had cutaneous melanoma. The interval from diagnosis to last known outcome was not different ( = 0.312) between horses that underwent monitoring alone (median: 2.0 y) and those that received treatment (mean: 2.25 y). Unassigned: Equine intraocular melanocytic neoplasms are highly associated with cutaneous melanoma and gray coat color, and they are more prevalent than previously published reports suggest. Unassigned: A complete ophthalmic examination is indicated for all horses with cutaneous melanoma. Additional research into the timing and rationale for treatment of intraocular melanocytic neoplasia is necessary. Néoplasie mélanocytaire intraoculaire équine. Unassigned: Décrire l’aspect clinique, l’histopathologie et le traitement de la néoplasie mélanocytaire intraoculaire équine chez le cheval adulte. Unassigned: Une étude rétrospective des dossiers médicaux a été réalisée. Les données enregistrées comprenaient le signalement, les résultats de l’examen oculaire, les résultats de l’examen physique, les interventions thérapeutiques et les résultats des cas. Les caractéristiques histopathologiques des globes énucléés ont été évaluées. Un test de Student a été utilisé pour évaluer les différences dans l’intervalle entre le diagnostic et le dernier résultat connu entre les chevaux recevant des interventions thérapeutiques et les chevaux soumis à une surveillance seule. Unassigned: Sur les 55 chevaux inclus, l’Arabe était la race la plus répandue (15/55, 27 %). Le gris était la couleur de robe la plus courante (85 %). L’examen physique a été réalisé pour 75 % des chevaux au moment du diagnostic, et parmi eux, 67 % présentaient un mélanome cutané. L’intervalle entre le diagnostic et le dernier résultat connu n’était pas différent ( = 0,312) entre les chevaux ayant subi une surveillance seule (médiane : 2,0 ans) et ceux ayant reçu un traitement (moyenne : 2,25 ans). Unassigned: Les néoplasmes mélanocytaires intraoculaires équins sont fortement associés au mélanome cutané et à la couleur du pelage gris, et ils sont plus fréquents que ne le suggèrent les rapports publiés précédemment. Unassigned: Un examen ophtalmologique complet est indiqué pour tous les chevaux atteints de mélanome cutané. Des recherches supplémentaires sur la planification et la justification du traitement de la néoplasie mélanocytaire intraoculaire sont nécessaires.(Traduit par D Serge Messier).
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This study investigates equine intraocular melanocytic neoplasia in adult horses, focusing on its clinical appearance, histopathology, and treatment methods. The research indicates that this condition is often related to cutaneous melanoma and gray coat color in horses. However, further research is necessary to refine treatment approaches for this type of cancer.
About the Study
The researchers conducted a retrospective review of medical records for this study, with 55 horses involved.
Several different factors were recorded from the medical records, including breed, coat color, findings from ocular and physical examinations, therapeutic interventions, and case outcomes.
The histopathological features of enucleated globes (globes that had been removed from the eye socket) were evaluated as a part of this study.
A statistical method called Student’s t-test was used to analyze the differences in the period from diagnosis to last known result between horses that were monitored alone and those that received treatment.
Key Findings
Of the 55 horses included in the study, the Arabian breed was most common, accounting for 27% of the total number. Additionally, gray was found to be the most common coat color, present in 85% of cases.
Physical examinations were conducted on 75% of the horses at the time of diagnosis. Of this 75%, two-thirds (67%) were found to have cutaneous melanoma.
There were no significant differences in the time from diagnosis to the last known outcome between horses that were monitored alone and those that received treatment, with a median of 2.0 years for monitored horses and a mean of 2.25 years for treated horses.
Conclusions and Future Directions
The results of the study suggested that equine intraocular melanocytic neoplasms are closely linked with cutaneous melanoma and the gray coat color. Furthermore, these conditions were found to be more common than previous reports had suggested.
A complete ophthalmic examination is recommended for all horses diagnosed with cutaneous melanoma, given the association found in this study.
Further research is necessary to investigate the timing and rationale behind treatment strategies for intraocular melanocytic neoplasia in horses.
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, 1008 West Hazelwood Drive, Urbana, Illinois 61802, USA.
Gemensky Metzler, Anne M
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, 1008 West Hazelwood Drive, Urbana, Illinois 61802, USA.
McMullen, Richard J
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, 1008 West Hazelwood Drive, Urbana, Illinois 61802, USA.
Wiggans, K Tomo
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, 1008 West Hazelwood Drive, Urbana, Illinois 61802, USA.
Labelle, Philippe
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, 1008 West Hazelwood Drive, Urbana, Illinois 61802, USA.
Hamor, Ralph E
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, 1008 West Hazelwood Drive, Urbana, Illinois 61802, USA.
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