Low-dose ARA-C consistently induces hematologic responses in the clinical 5q- syndrome

Five patients with the classical clinical syndrome associated with a deletion of the long arm of chromosome 5, i.e., anemia, macrocytosis, and thrombocytosis, or a normal platelet count, were treated successfully with subcutaneous low-dose cytosine arabinoside (LDARA-C). Prior therapy with other drugs had failed in four of the five patients. A total of nine complete and one partial hematologic responses were induced in five patients. Duration of the first hematologic response ranged from 3 to 30+ months. Two patients (cases 3 and 4) continue in their first hematologic response at 29 and 30 months. Upon relapse, up to three responses could be reinduced in two patients. Duration of the subsequent hematologic responses in case 1 was 16, 8, and 10 months and case 2 achieved two responses of 15 and 18+ months duration. LDARA-C therapy was associated with mild to severe neutropenia and moderate to severe thrombocytopenia. Thus, subcutaneous LDARA-C is highly effective in the treatment of patients with myelodysplasia associated with deletion of the long-arm of chromosome 5 (5q-).