[Successful treatment with combination of all-trans retinoic acid (ATRA) and rhG-CSF a relapsed acute promyelocytic leukemia with umbilical tumor].

A 48-year-old female was admitted to our hospital because of pancytopenia and pneumonia in February, 1993. The increase of abnormal promyelocytes with t (15; 17) and PML-RAR mRNA was detected in bone marrow aspirate and a diagnosis of acute promyelocytic leukemia was made. She obtained complete remission after the administration of all-trans retinoic acid (ATRA) and following chemotherapy. Then she received peripheral blood stem cell transplantation in September, 1993. However she noticed a umbilical tumor in June, 1995. Abnormal promyelocytes were demonstrated not only in bone marrow aspirate but also in the umbilical tumor. Because of the poor response to ATRA and development of fever, a side effect of ATRA, G-CSF and prednisolone were administrated together with ATRA. After the combined therapy, umbilical tumor disappeared and she obtained complete remission again. These findings suggest that combined therapy of ATRA and G-CSF is effective to the low responder to ATRA and that combined use of ATRA and prednisolone reduces the side effect of ATRA without diminishing the favorable effect on differentiation.