Case of primary digital embryonal rhabdomyosarcoma in a cat

An 11-year-old Turkish angora cat was presented with a mass in the right forelimb phalangeal region. Two years earlier, the cat had undergone surgical resection of a dorsal interscapular mass. Before initiating anticancer therapy, surgical incisional biopsy of a phalangeal region mass was done, followed by histopathologic and immunohistochemical analyses. The tumor cells demonstrated positive immunohistochemical labelling for desmin, vimentin, and myoblast determination protein 1, supporting a diagnosis of rhabdomyosarcoma (RMS). Histologic features were consistent with an embryonal subtype of RMS. Accordingly, a right forelimb amputation was completed. To our knowledge, this is the first reported case of a digital RMS in a cat. Because RMS is a rare tumor in cats, it is essential to study the clinical presentation, hematologic and serologic changes, treatment responses, and prognosis. Suitably, this case report provides valuable insight into the management of similar cases in cats. Key clinical message: This first reported case of digital RMS in a cat highlights the importance of studying the clinical presentation and treatment of RMS in feline patients.