A Roman goose (Anser anser domesticus) was presented with a large mass on the left lateral side of the neck with a smaller satellite mass on the right. Utilizing radiography, blood tests, and histological and immunohistochemical investigations, a diagnosis of cutaneous T-cell lymphoma associated with hypercalcemia of malignancy was established. The involvement of oncogenic viruses was ruled out through PCR and RT-PCRs. Due to the mass's considerable size, location, and post-treatment management challenges, the owner opted against surgery and chemotherapy. Glucocorticoids were administered upon the great enlargement of a second mass on the base of the right side of the neck and the worsening of clinical signs but proved entirely ineffective. Due to the disease progression, euthanasia was elected, and a post-mortem investigation ensued to clarify the extent and confirm the lesion's nature. Similar histological and immunohistochemical findings confirmed the final diagnosis of epitheliotropic T-cell lymphoma with cutaneous and esophageal involvement.