- Group I: Patients are observed if their transient myeloproliferative disorder (TMD) does not require intervention. Patients who require therapy for TMD undergo leukapheresis or exchange transfusion for up to 3 consecutive days. If the TMD does not resolve or there is significant organ involvement, patients receive low-dose cytarabine IV continuously on days 0-4. Treatment repeats at least every 2 weeks for up to 4 courses. Patients who experience a recurrence of TMD at least 8 weeks after resolution or have refractory disease may proceed to group II for further treatment.