Torsade de pointes in a patient with severe hypercalcaemia and multiple myeloma.

We report a case of a 48-year-old female patient with newly diagnosed multiple myeloma. She developed recurrent torsade de pointes and required cardiopulmonary resuscitation and defibrillation. Atrial arrhythmias in patients with multiple myeloma and hypercalcaemia have been described, but, to the best of our knowledge, this is the first report of torsade de pointes in this setting.

Alemtuzumab in chronic lymphocytic leukemia: final results of a large observational multicenter study in mostly pretreated patients.

This retrospective study evaluated the benefit of alemtuzumab monotherapy in unselected patients with advanced B-cell chronic lymphocytic leukemia (CLL) and prolymphocytic leukemia (B-PLL) to definitely describe the impact of this antibody in clinical routine use. Data were collected from 208 consecutive, mainly pretreated, patients with CLL (n = 202), and B-PLL (n = 6) who had received alemtuzumab. Response, progression-free survival (PFS), and overall survival (OS) in various settings were assessed, and toxicities were documented. In these routine patients, a comparably low cumulative dose of alemtuzumab (median, 403 mg) was applied. In CLL, overall response rate was 32 %, and various pre-therapeutic parameters were predictive for inferior response, among them, the prior administration of ≥3 therapy lines (P < 0.001), refractoriness to fludarabine (P = 0.002), and bulky lymphadenopathy (P = 0.003). PFS and OS after start of alemtuzumab were 6.2 and 21.0 months, respectively. Bulky lymphadenopathy was the prominent risk factor for both inferior PFS (P < 0.001) and OS (P = 0.002). In B-PLL, four patients experienced a fatal outcome, whereas two patients had some benefit with alemtuzumab. The main adverse effects were CMV reactivation (20 %) and a broad spectrum of infections, which together were the main reasons for treatment interruption and/or premature termination. In conclusion, alemtuzumab administered even at low dose levels was effective but overall considerably toxic in routine CLL patients. We emphasize that alemtuzumab remains an important therapeutic option in subsets of CLL patients.

Use of five-color staining improves the sensitivity of multiparameter flow cytomeric assessment of minimal residual disease in patients with acute myeloid leukemia.

Application of five-color staining may improve quantification of minimal residual disease by multiparameter flow cytometry in acute myeloid leukemia. We analysed bone marrow samples in 139 cases using a comprehensive antibody panel with five-color combinations. Sensitivity was estimated by quantification of leukemia-associated aberrant immunophenotype (LAIP)-positive cells for each LAIP in 18 normal bone marrow (BM) samples. The logarithmic difference (LD) in LAIP-positive cells between leukemic and normal BM amounted to a median of 3.32 (range 1.76 - 4.89). Skipping one color resulted in an increase of LAIP-positive normal bone marrow cells while percentages of LAIP-positive leukemic cells changed only marginally (median gain in LD = 0.54; maximum gain = 3.30). Because regenerating bone marrow has not been used as control data are most important to post-therapy checkpoints. In 32 patients with clinical follow-up, a LD higher than the median (3.25) at the follow-up checkpoint corresponded to a longer event-free survival. These data suggest that the application of five-color staining significantly improves the sensitivity and accuracy of the method.

Leukemic cells and aberrant phenotypes in acute leukemia patients: a flow cytometry analysis.

The aim of this study was to evaluate the heterogeneity of immunophenotype features in acute leukemia patients and to detect the presence of leukemia-associated immunophenotypes. We prospectively investigated the phenotype of blast cells from 44 adult acute leukemia patients using a large panel of monoclonal antibodies by multiparametric flow cytometry. Thirty-three patients were classified as AML according to the FAB classification. Eleven patients were diagnosed as ALL (10 cases B-ALL, 1 case T-ALL) according to both FAB and immunnophenotyping. We found leukemia-associated phenotypes in 28 of 33 AML patients (84.8%) and in 8 of 11 ALL patients (72.7%). In 61.1% of patients more than one aberrant phenotype was observed. Linear infidelity was the most frequent aberrancy in both AML (64.3%) and ALL (37.5%) subgroups. The present study shows that MFC is a helpful method for sufficient identification of leukemic cells and for determination of blast cells immunophenotype heterogeneity. The double stain flow cytometry in our study revealed aberrant phenotypes in up to 81.8% patients.

[New findings in the diagnosis of minimal residual disease in acute leukemia with emphasis on flow cytometry]. / Novsie poznatky o diagnostike minimálnej reziduálnej choroby u akútnych leukémií so zameraním na prietokovú cytometriu.

The authors present a review of contemporary findings of investigations of minimal residual disease in patients with acute leukaemia. They present brief information on different monitoring techniques and on their practical application. Attention is paid above all to multiparameter flow cytometry as this method is used in their laboratory work.