Haemopoietic stem cell autografts for leukaemia

Autologous bone marrow transplantation in leukemia

In patients without HLA-identical donors autologous bone marrow transplantation should be considered as an alternative to conservative treatment of recurrent malignancies. Any patient in complete remission is suitable for an autologous bone marrow transplantation. Bone marrow is aspirated from the patient during complete remission, frozen, and stored at -196 degrees C, and it can be used for hematopoietic reconstitution after high-dose chemotherapy and radiotherapy of the patient. In patients with solid malignant tumors or leukemia the elimination of clonogenic tumor cells from the graft by means of physical separation techniques has not been successful. However, studies in mice and more recently in patients indicate that antibodies destroy residual leukemic cells of the bone marrow transplant without jeopardizing the capacity for regeneration. During our first study in children with acute lymphoblastic leukemia, bone marrow was taken from 50 patients in remission and cryopreserved. Preservation time ranged from 1 to 60 months and the mean number of aspirated nucleated bone marrow cells was 4 X 10(8)/kg body weight (1.9 - 7.4 X 10(8)/kg). After cryopreservation the stem cell viability of the standard samples was 80% - 100%. Autologous bone marrow was transplanted in five patients with common ALL (cALL). The transplant was prepared by incubation with specific antisera of high cytotoxic, selective activity against cALL cells. Our preliminary results show that bone marrow cells aspirated in remission and prepared with antileukemic antisera stimulate repopulation of the recipient's bone marrow and effect hematopoietic regeneration.

Histological study of the bone marrow in chronic granulocytic leukaemia in blast transformation. I. Serial observations before and after autografting

Sixteen patients with chronic granulocytic leukaemia (CGL) in blast cell transformation (BT) were studied by means of serial bone marrow trephine biopsies (BMB). The BMB were performed during the following stages of the disease: 1 at diagnosis of BT, 2 following ablative therapy and 3 during haematological recovery following autografting. In 10 of the 16 patients, BT was recognized by the presence of a distinctive infiltration with blast cells with a single large hyperchromatic nucleolus. In four of the 16 patients, the diagnosis of BT could only be made by BMB since simultaneous marrow aspiration yielded either a dry tap or no marrow fragments; in two of these four patients the BT was focal in the BMB specimen. Following ablative therapy and during haematological regeneration after autografting, BM aspirates were unsatisfactory in most cases and they were inadequate to assess cellularity or the presence of residual blasts. In contrast, sections of BMB showed clearly whether a decrease in cellularity took place or, in some, residual blasts were still present. BMB samples obtained 2 weeks after autografting showed haemopoietic regeneration consisting of discrete foci of either erythroid, granulocytic or megakaryocytic precursor cells. We conclude that BMB is essential for diagnosing CGL in BT, for monitoring the progress of these patients after therapy and in assessing the haemopoietic regeneration following autografting.

Buffy coat autografts for patients with chronic granulocytic leukaemia in transformation

We have treated 20 patients with chronic granulocytic leukaemia (CGL) in transformation with cytotoxic drugs or with cytotoxic drugs and whole-body irradiation followed by transfusion of autologous blood cells collected at diagnosis and stored in liquid nitrogen. The mean number of nucleated cells autografted was 25.1 X 10(8)/kg (range: 12.5-40.1). Full myeloid engraftment occurred in 18 patients; it was partial in one patient and unassessable in another. The median survival for the 20 patients post-graft was 14 weeks. Two patients are alive, one now in recurrent transformation, and one in second chronic phase that has lasted 52 weeks. For the 18 patients who died the mean survival was 24 weeks (range: 2-125). Two patients with predominantly myelosclerotic transformation showed evidence of engraftment. One patient successfully autografted developed features consistent with graft-versus-host disease which proved fatal. We conclude that autografting may offer substantial palliation for some but not all patients with CGL in transformation.