Tongue hyperpigmentation following idarubicin-based induction therapy in adverse-risk acute myeloid leukemia

Anthracycline-derived antibiotics are prescribed frequently for treating patients diagnosed with acute myeloid leukemia (AML) and are notable for their association with mucositis and myelosuppressive properties; however, chemotherapy-induced oral hyperpigmentation resulting from the use of anthracycline antibiotics is rare and poorly documented, especially for idarubicin. A 29-year-old female presenting with fever and anemia along with bleeding manifestations was subsequently diagnosed with AML (FAB M4) based on laboratory findings of a hemoglobin level of 8.9 g/dL, a platelet count of 12 × 10 ⁹ /L, and leukocytosis. The diagnosis was confirmed by bone marrow examination, which also identified FLT3-ITD and WT1 mutations through molecular studies, indicating that she had an European Leukemia Net 2017 risk classification of high risk. Induction chemotherapy was given using a 5 + 3 regimen (idarubicin + cytarabine). Day 19 after beginning therapy, the patient developed diffuse hyperpigmentation of the lesion, which was asymptomatic and showed no evidence of ulceration and infection. According to the Naranjo scale, the association between the drug and adverse reaction is possible. The patient was treated with topical triamcinolone but was allowed to continue the chemotherapy treatment without interruption. Idarubicin-associated tongue hyperpigmentation is a rare, benign, and reversible adverse effect. Recognition of this entity is important to avoid misdiagnosis and unnecessary modification of potentially life-saving chemotherapy.