Summary Analysis of short tandem repeats (STR) is the predominant method for post‐transplant monitoring of donor engraftment. It can enable early detection of disease relapse, level of engraftment and provide useful information on the graft‐versus‐host disease (GVHD)/graft‐versus‐tumour (GVT) effect, facilitating therapeutic intervention. Harmonization and standardization of techniques and result interpretation is essential to reduce the impact of laboratory variability on both clinical management and the results of multi‐centre clinical trials. However, the United Kingdom National External Quality Assessment Service for Leucocyte Immunophenotyping (UK NEQAS LI) has highlighted significant issues inherent in STR testing that impact upon inter‐ and intra‐ laboratory variation. We present here consensus best practice guidelines and recommendations for STR chimerism testing, data interpretation and reporting that have been drawn up and agreed by a consortium of 11 UK and Eire clinical laboratories. This document uses data obtained from the UK NEQAS LI Post‐Stem Cell Transplant (SCT) Chimerism Monitoring Programme.

SummaryMolecular testing for the BCR-ABL1 fusion gene by real time quantitative polymerase chain reaction (RT-qPCR) is the most sensitive routine approach for monitoring the response to therapy of patients with chronic myeloid leukaemia. In the context of tyrosine kinase inhibitor (TKI) therapy, the technique is most appropriate for patients who have achieved complete cytogenetic remission and can be used to define specific therapeutic milestones. To achieve this effectively, standardization of the laboratory procedures and the interpretation of results are essential. We present here consensus best practice guidelines for RT-qPCR testing, data interpretation and reporting that have been drawn up and agreed by a consortium of 21 testing laboratories in the United Kingdom and Ireland in accordance with the procedures of the UK Clinical Molecular Genetics Society.

Summary Twenty‐two patients with acute myeloid leukaemia were recruited into a phase I/II clinical trial investigating the vaccination of patients in complete remission (CR) with autologous dendritic‐like leukaemia cells (DLLC). At trial entry, leukaemia cells were harvested and tested for their ability to undergo cytokine‐induced dendritic cell differentiation. Patients were then treated with intensive chemotherapy. Five patients achieved both CR and had leukaemia cells that successfully underwent differentiation and therefore proceeded to vaccination. Four escalating doses of DLLC were administered weekly by subcutaneous injection. Vaccination was generally well tolerated although one patient developed extensive eczema and an increased antinuclear factor titre possibly indicating induction of autoimmunity. Development of anti‐leukaemic T‐cell responses was assessed by enzyme‐linked immunospot analysis of gamma‐interferon secreting T lymphocytes and by human leucocyte antigen tetramer analysis for WT1‐specific T cells. Increases in anti‐leukaemic T‐cell responses were demonstrated in four patients, but only two of the five remained in remission more than 12 months postvaccination. The study has demonstrated that generation of DLLC is feasible in only a subgroup of patients and is currently neither broadly applicable or clinically effective.

No abstract

Summary. Peripheral blood stem cell (PBSC) mobilization using idarubicin and cytarabine was investigated in 40 patients with chronic myeloid leukaemia in first chronic phase (CML CP1). Disease contamination was evaluated in harvests from 41/44 (93%) mobilization episodes. Using cytogenetics, 22/37 (59%) showed a complete or major response; Southern blot analysis demonstrated a complete or major response in 9/17 (53%). No harvests were RT-PCR negative. In the 41 evaluable episodes, more complete or major responses were seen when PBSC mobilization occurred within 24 months [17/23 (74%) versus 6/18 (33%); P ¼ 0 : 02] and within 12 months of diagnosis [10/11 (91%) versus 13/30 (43%); P ¼ 0 : 018]. 20 patients underwent PBSC transplantation and 18/20 successfully engrafted. Post-transplant cytogenetic analysis was available on 15 cases, of whom five achieved a major cytogenetic response at 1-3 months, with five partial cytogenetic remissions. Two of 40 patients died during mobilization therapy (5%) and three of 20 after the transplant (15%). Overall mortality was high at five of 40 patients, and the procedural mortality was 20%. This study demonstrates that Ph-negative PBSCs can be mobilized in a significant proportion of patients with CML CP1, with the best results observed within a year of diagnosis. These cells can subsequently be used for autologous transplantation, however, the impact on long-term survival requires longer follow-up, and potential benefits may be compromised by the high mortality.