Fludarabine/cyclophosphamide was well tolerated and allowed consistent engraftment in lymphoma allografted patients. Response rates were high in this group of refractory and heavily pretreated patients. This dual procedure seems to be most promising in patients with end-stage malignant lymphomas.

Intensive chemotherapy given in early chronic phase of CML is well tolerated and results in high numbers of circulating Ph1-negative precursor cells.

We have previously reported that mobilization of Philadelphia (Ph) chromosome-negative progenitors is possible in a significant number of Ph1-positive acute lymphoblastic leukaemia (ALL) and chronic myelogenous leukaemia (CML) patients. In this pilot study we employed the same approach for patients with RAEB-t, secondary AML (sAML) and therapy-related AML (t-AML). All patients except one had double or complex cytogenetic abnormalities in marrow cells before mobilization therapy. All patients received an idarubicin-containing regimen (mini-ICE protocol) followed by rh-G-CSF and the first leukapheresis was performed as they were recovering from aplasia. In six out of nine patients the leukapheresis product was entirely karyotypically normal, combined with a significant number of CFU-GM. CD34+ cells and LTC-IC. Recovery time from mobilization therapy was short and no patient died as a result of the procedure. To date, three patients have undergone autografting using their karyotypically normal collections, of which two (sAML) are alive with karyotypically normal marrow a few months after autografting.

Summary.To determine if reducing the intensity of the mobilizing chemotherapy protocol used would alter the number and/or quality of the progenitors mobilized in patients with chronic myelogenous leukaemia (CML), we undertook a pilot study. 36 consecutive CML patients previously treated only with hydroxyurea were given mobilization therapy within 12 months of diagnosis. 17 patients were treated by the ICE protocol and 19 patients received the mini-ICE protocol. The leukapheresis product collected from 22/36 patients (62%) was entirely Ph-negative. The cytogenetic results between ICE and mini-ICE-treated protocols were not significant, although the reduction in median days of hospitalization required for the mini-ICE versus the ICE protocol was highly significant (P < 0·0001). There was no significant difference in the yield of CD34 þ cells and CFU-GM collected. No patient in the mini-ICE protocol experienced high-grade oral mucositis and GI toxicity whereas three such cases occurred with the ICE protocol. No patient died of the mobilization procedure in either group.

Intensive chemotherapy given in early chronic phase of chronic myelogenous leukemia (CML) has resulted in high numbers of circulating Philadelphia (Ph) chromosome–negative hematopoietic progenitor cells (HPC). We have autografted 30 consecutive patients with CML in chronic phase with HPC collected in this way to facilitate restoration of Ph-negative hematopoiesis in bone marrow after high-dose therapy. Hematopoietic recovery to greater than 0.5 ×109/L neutrophils and to greater than 25 × 109/L platelets occurred in all patients, a median of 13 (range, 9 to 32) days and 16 (range, 6 to 106) days postautograft, respectively. Regenerating marrow cells were Ph-negative in 16 (53%) patients and greater than 66% Ph-negative in 10 (33%) patients. Twenty-eight patients are alive 6 to 76 months (median, 24 months) after autografting. Three patients have developed blast crisis from which 2 have died. Eight patients are in complete cytogenetic remission at a median of 20 (range, 6 to 44) months with a median ratio BCR-ABL/ABL of 0.002 (range, <0.001 to 0.01). Eight patients are in major cytogenetic remission at a median of 22 (range, 6 to 48) months. No patient died as a consequence of the treatment. All patients had some degree of stomatitis that was severe in 15 (50%) patients. Gastrointestinal and hepatic toxicities were observed in about one fourth of patients. Thus, autografting with Ph-negative mobilized HPC can result in prolonged restoration of Ph-negative hematopoiesis for some patients with CML; moreover, most autograft recipients report normal or near normal activity levels, suggesting that this procedure need not to be associated either with prolonged convalescence or with chronic debility.