High-dose idarubicin in combination with Ara-C in patients with relapsed or refractory acute lymphoblastic leukemia: a pharmacokinetic and clinical study.

OBJECTIVE: High dose (HD) Ara-C combined with a single HD idarubicin dose (IDA) is an efficient and safe salvage regimen for patients with refractory or relapsed acute lymphoblastic leukemia as indicated by phase II studies. No data are available on the pharmacokinetics of IDA after a rapid HD intravenous infusion. An open phase II pharmacokinetic and clinical study was performed to evaluate antileukemic efficacy, IDA pharmacokinetics and to investigate the presence of IDA and its reduced metabolite idarubicinol (IDAol) in cerebrospinal fluid (CSF) of patients treated with HD-IDA. PATIENTS AND METHODS: Twenty-five patients with refractory or relapsed acute lymphoblastic leukemia received Ara-C 3 g/m2 from days 1-5, idarubicin (HD-IDA) 40 mg/m2 as rapid intravenous (i.v.) infusion on day 3 and subcutaneous G-CSF 5 microg/kg from day 7 until PMN recovery. Pharmacokinetics of IDA was evaluated after HD idarubicin administration in nine of these patients. CSF samples were collected in 15 patients at different times. IDA and IDAol concentrations were quantified by a validated HPLC assay described in detail elsewhere. RESULTS: Eleven patients (44%, 95% CI: 23-65%) achieved complete remission with median disease free survival for 6 months. After administration of HD-IDA i.v. bolus of 40 mg/m2, plasma level profiles of unchanged drug and IDAol were similar to those previously described after standard dose and measured with the same analytical method. The mean terminal half-life measured for IDA in this group of patients (14.9 h) was not significantly different from the mean value observed after standard dose (13.9 h, P=0.72). IDAol t1/2 was also similar after HD-IDA (46.2 h) and standard dose (39.4 h, P=0.79). Pharmacokinetic data reveal that in our series of patients IDA and IDAol clearances are significantly higher than those observed in patients treated with 12 mg/m2 of IDA but, although the administered dose (mg/m2) of the drug is 3.3 times higher, IDA exposure (measured in terms of AUC) is only 2.3 times and IDAol exposition 2.1 times greater. Furthermore, HD infusion resulted in a ratio between the AUC of parent drug and idarubicinol not different from the value observed with the standard-dose. IDA and IDAol were measurable only in 3 of the 15 cerebrospinal fluid samples collected. CONCLUSION: Responses observed in our series are comparable to those reported with other salvage regimens. The IDA exposure lower than expected may explain the safety of the single i.v. administration of 40 mg/m2 of IDA, combined with HD Ara-C, with a degree of myelosuppression equivalent to that reported with this agent administered in standard doses. Our data do not allow us to clearly attribute this behavior to a pharmacokinetic non-linearity since the baseline creatinine clearance, even within normal values, and patient age are significantly different in the two groups. Cerebrospinal fluid penetration was poor, reaching levels not considered as cytotoxic.

The role of quantitative polymerase chain reaction in the management of follicular lymphoma patients.

AIMS AND BACKGROUND: In order to increase the prognostic significance of polymerase chain reaction (PCR) data it has been suggested that quantitative PCR can be used to measure tumor burden. However, this option has not yet been definitely supported or refuted in patients with follicular lymphoma (FL). We decided to evaluate whether knowledge of the quantitative level of minimal residual disease and its variations can be of use in the management of FL patients. METHODS: We used qualitative and competitive PCR to study 11 patients with refractory or relapsed FL harboring the t(14;18) translocation who underwent autologous (nine patients) or allogeneic (two patients) stem cell transplantation (SCT). Competitive PCR was performed with a multiple competitor carrying specific sequences including Bcl2/IgH MBR and mcr, and the beta-globin gene. RESULTS: After a median post-SCT follow-up of 44 months (range, 12-62), overall survival was 91% and disease-free survival 82%. The quantitative PCR data showed that: 1) effective chemotherapy before SCT substantially (1-2 log) reduced the tumor burden in the bone marrow (BM); 2) the increase in rearranged DNA detected in BM was associated with disease progression and relapse; 3) a PCR-negative autograft seemed to lead to lasting molecular remission even when it was performed in patients with a low level of BM infiltration before transplant; and 4) allo-SCT made and maintained the BM PCR negative even in the presence of a greater tumor burden before SCT. Six of the nine patients having CR after SCT (four auto and two allo) are in continuous molecular remission. CONCLUSIONS: In FL patients qualitative and quantitative PCR may provide data that can be helpful for the prognostic evaluation of tumor progression and the early detection of impending relapse by highlighting biological features such as the quality of the infused material, the tumor burden at transplant, and the behavior of tumor cells after transplant.

Predictive variables for malignant transformation in 452 patients with asymptomatic IgM monoclonal gammopathy.

The natural history of asymptomatic IgM monoclonal gammopathies (MG) and variables predicting evolution to symptomatic lymphoproliferative disorders were investigated in 452 patients diagnosed from 1975 to 2001. Univariate and multivariate Cox models were used to identify possible predictors of disease progression. At a median follow-up of 49 months (range, 12 to 233), 41 cases (9.1%) evolved to symptomatic Waldenstrom's macroglobulinemia (n = 36), non-Hodgkin's lymphoma (n = 2), B-cell chronic lymphocytic leukemia (n = 1), IgM multiple myeloma (n = 1), and primary amyloidosis (n = 1); the median interval from diagnosis was 53 months (range, 12 to 154). The cumulative probabilities of transformation into a symptomatic lymphoproliferative disease at 5 and 10 years were 8% (95% confidence interval [CI], 6% to 12%) and 21% (95% CI, 16% to 29%), respectively. At univariate analysis, monoclonal component size and hemoglobin level as continuous parameters, lymphocytosis (>4 x 10(9)/L), bone marrow lymphoplasmacytoid infiltration (>10%), erythrocyte sedimentation rate (>40 mm/h), and detectable Bence Jones proteinuria were significantly related with evolution probability. At multivariate analysis, paraprotein level (P <.0001), hemoglobin level (P <.05), and lymphocytosis (P <.0001) independently predicted malignant evolution (P <.0001). In conclusion, patients with asymptomatic IgM-MG showing hematological features predictive of progression should be carefully monitored in view of an early treatment of the disease.

Smouldering Waldenstrom's macroglobulinemia: factors predicting evolution to symptomatic disease.

Factors predicting evolution to symptomatic disease were investigated in 27 patients with smouldering Waldenstrom's macroglobulinemia (SWM) among 172 patients with Waldenstom's macroglobulinemia (WM), selected on the basis of the following criteria: (1) IgM paraprotein > 3 g/dL, and/or (2) bone marrow (BM) lymphoplasmacytoid (LPC) infiltration >or= 30%, and/or (3) diffuse infiltration pattern on BM biopsy, and (4) no treatment requirement for at least 12 months. Cumulative probability of survival was calculated by means of Kaplan-Meier. The Mantel and Haenszel test and multivariate Cox model were used to identify possible predictors for evolution. At a median follow-up of 79 months (range, 14 to 204), 11 patients (40.7%) showed progression to symptomatic disease, with the median interval from diagnosis being 46 months (range, 12 to 154). Event-free survival (EFS) at 5 and 10 years was 65% (95% confidence interval [CI], 45% to 85%) and 53% (95% CI, 31% to 75%), respectively. At multivariate analysis, paraprotein > 3 g/dL (hazard ratio [HR], 15.1; 95% CI, 3.01 to 75.64; P <.0009) and hemoglobin 3 g/dL and hemoglobin levels