What Is Your Diagnosis? Fine-Needle Aspirate From a Subcutaneous Preputial Mass in a Ferret

A 3-year-old male ferret presented with alopecia, lethargy, and a subcutaneous preputial mass, which was diagnosed as apocrine gland adenocarcinoma through cytologic and histologic evaluation. The mass exhibited aggressive characteristics typical of malignant apocrine neoplasms, which are common in ferrets and often found in areas with high concentrations of apocrine glands. Despite surgical intervention, the ferret did not survive post-operatively. The study highlights the cytologic features of the tumor, including unique eosinophilic granules, and suggests further investigation into their potential prognostic significance. The case adds to the understanding of apocrine adenocarcinomas in ferrets.