Unusual extramedullary relapse of acute lymphoblastic leukemia in a bone marrow transplant patient.

An unusual form of relapse of acute lymphoblastic leukemia is described in a woman who developed a solitary large focal mass of lymphoblasts in her liver and an isolated polypoid lymphoblastic mass in her uterus after bone marrow transplantation, despite continued marrow remission. Extramedullary visceral leukemic relapse in the form of such discreet focal masses is highly unusual and to our knowledge has not been described in this setting. Awareness and recognition of atypical forms of relapse are important since such a diagnosis carries critical therapeutic and prognostic implications.