mucocutaneous relapse as an unusual presentation of t-lineage acute lymphoblastic leukemia

acute leukemias represent approximately 30% of malignant diseases in patients under the age of 15 years. leukemic infiltration of the central nervous system and testis are common events, particularly as sites of relapse in the third year after diagnosis. management of acute lymphoblastic leukemia is based on long-term chemotherapy, leading to a cure rate of approximately 80% of children and adolescents. despite this elevated cure rate, approximately 20% have disease relapse. bone marrow is the most frequent site of relapse followed by the central nervous system. nevertheless, relapse can occur in any tissue or organ. recurrence in the mucocutaneous area is extremely uncommon and rare in childhood acute lymphoblastic leukemia. to our knowledge, a few case reports (mostly in adolescents or adults) have been published regarding relapse in the mucosal area (oral cavity) and skin. most patients had concomitant bone marrow relapse. in this paper we report a case of recurrence of t-cell acute lymphoblastic leukemia in the hard palate, lip and skin of a child without bone marrow relapse.