Tongue plasmacytoma in a dog treated with adjuvant metronomic melphalan

A 9-year-old female crossbred dog was referred due to a tongue neoformation. A marginal resection was performed to proceed with the histopathological examination, which indicated malignant round cell neoplasia, and immunohistochemical staining diagnosed the mass as plasmacytoma. The owner refused another surgical intervention to extend margins and approach another growth verified on the ventral surface of the base of the tongue. Thus, the patient underwent three months of metronomic chemotherapy with melphalan. The disease progression was not detected after two years of follow-up. This report shows that daily low-dose melphalan may be used as an adjuvant treatment option for oral plasmacytoma in dogs when clean margins cannot be achieved.