2716

PHENOMENON OF CHILD ACUTE LYMPHOBLASTIC LEUKAEMIA WITH INCREASE IN IMMATURE HAEMATOPOIETIC CELLS DURING THE EARLY RECOVERY PHASE CHEMOTHERAPY

Wu XD, Li CHF, Hu PH, He YL, Zhang YM

Nanfang Hospital, Guangzhou, China

Objective: To determine whether increases in marrow lymphoid progenitors and lymphoblasts during continuing consolidation treatment and extramedullary leukaemia prophylaxis following complete remission from induction chemotherapy in the course of treatment of acute lymphoblastic leukaemia are relapse.

Methods: Seven cases were our in-patient during 1992-2000. All except two were males, the oldest being eleven years old, youngest being 2 years old. The intensification depends on age, immunophenotyping and FAB classification. After intensive chemotherapy, regular bone marrow examination showed increases in immature lymphoid progenitors from 6% to 25%. We wait for 8 to 25 (average 16) days and do another regular bone marrow examination to have evaluation. The whole group of our patients did not have any clinical signs of relapse. All subjects did not have evidence of any viral infection, such as upper respiratory tract infection. Bone marrow examination showed active nucleated cell proliferation. The peripheral blood smear remained normal.

Results: Regular bone marrow examination of six patients show complete remission. Only one patient still showed increases in immature lymphoid progenitors. Two patients decided to withdraw from treatment and relapsed only after more than one year of follow up. The rest of the patients had event free survival.

Conclusion: Increases in marrow lymphoid progenitors and lymphoblasts during continuing consolidation treatment and extramedullary leukaemia prophylaxis following complete remission from induction chemotherapy in the course of treatment of acute lymphoblastic leukaemia mostly are not relapse.