ABSTRACT
The small molecule receptor tyrosine kinase (RTK) inhibitor SU5416 targets the vascular endothelial growth factor receptor 2 and the stem cell factor receptor c-kit. Herein is described the successful treatment of a 65-year-old woman with SU5416, in second relapse of acute myeloid leukemia (AML) and refractory toward standard chemotherapy regimens. After 12 weeks of treatment with SU5416, the blast cell counts (blood and bone marrow) decreased to undetectable levels and the peripheral blood cell counts normalized with the exception of the platelet count (50-80 x 10(9)/L [50-80 x 10(3)/microL]). The duration of the remission is longer than 4 months during maintenance therapy with SU5416. Microvessel density in the patient's bone marrow dropped from 33.4 to 12.3 microvessels/x500-field 8 weeks after SU5416 administration and remains in the normal range. This is the first report of a stable remission achieved after administration of the RTK inhibitor SU5416 in a patient with AML relapse.
Subject(s)
Indoles/administration & dosage , Leukemia, Myeloid/drug therapy , Pyrroles/administration & dosage , Acute Disease , Angiogenesis Inhibitors/administration & dosage , Antineoplastic Agents/administration & dosage , Bone Marrow Cells/chemistry , Endothelium, Vascular/chemistry , Endothelium, Vascular/cytology , Female , Humans , Immunohistochemistry , Middle Aged , Protein-Tyrosine Kinases/antagonists & inhibitors , Receptor Protein-Tyrosine Kinases/drug effects , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Growth Factor/drug effects , Receptors, Growth Factor/metabolism , Receptors, Vascular Endothelial Growth Factor , Remission Induction/methodsABSTRACT
We report a case of a 28-year-old man with acute lymphoblastic leukemia who developed rhinocerebral zygomycosis during induction chemotherapy. This life-threatening fungal infection is an infrequent cause of neutropenic fever, and is occasionally found in patients with leukemia and lymphoma, or patients with severely compromised defence mechanisms due to other diseases. It is caused by moulds belonging to the Mucoraceae family, and is characterized by local destruction of the affected organ. In our patient, the infection spread from the paranasal sinuses to the right orbit, destroyed intraorbital structures and resulted in blindness within days. Biopsy from the right maxillary sinus was performed and mucormycosis was suspected through microscopic examination. Culture of the resected specimen identified Rhizopus arrhizus as the causing agent. Treatment of zygomycosis should consist of radical surgical debridement of the infected tissue, together with intensive broad-spectrum antimycotic therapy with amphotericin B. What could be learned from this case is, that aggressive approaches to identify the cause of infection is necessary, and that aggressive treatment strategies are inevitable to overcome the infection. Furthermore, treatment of the underlying disease should be continued as soon as possible.
