A first Czech analysis of 1887 cases with monoclonal gammopathy of undetermined significance.

INTRODUCTION: Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant condition with a risk of malignant conversion. PATIENTS AND METHODS: With the aim to estimate the cumulative risk MGUS progression to hematologic malignancies, we analyzed a nationwide population-based cohort of 1887 MGUS patients from the Czech Registry of Monoclonal Gammopathies (RMG) between 2007 and 2013. RESULTS: During the follow-up period (median 4 years; range 0.6-34.8), progression to hematologic malignancies was observed in 8.6% (162 of 1887) of patients. Factors associated with progression were as follows: M-protein concentration ≥1.5 g/dL, pathological sFLC (<0.26 or >1.65) ratio, bone marrow plasma cells (BMPCs) in cytology >5%, immunoparesis, age ≥69 years, and the level of serum hemoglobin at baseline <12.0 g/dL. Combining these factors, we propose a new risk model (CMG model). The risk of progression at 10 years was 1.6%, 16.9%, 22.9%, 39.4%, and 52.3%, respectively, if 0 (reference group), one, two, three, or four to five risk factors are present (P<.001) with HR 63 times higher compared to the reference MGUS group. CONCLUSION: The new CMG model was established with an advantage for better identification of MGUS patients at low risk.

Subcutaneous bortezomib in multiple myeloma patients induces similar therapeutic response rates as intravenous application but it does not reduce the incidence of peripheral neuropathy.

OBJECTIVE: Subcutaneous (SC) application of bortezomib has been recently introduced as a new application route in multiple myeloma (MM) patients. We performed an analysis to compare the outcomes of bortezomib-based therapy in multiple myeloma (MM) patients treated using either intravenous (IV) or subcutaneous (SC) route of administration. PATIENTS AND METHODS: During January 2012 through December 2013, we performed a retrospective analysis of 446 patients with MM treated with bortezomib-based regimens (either once weekly - 63% or twice weekly - 27%) in both, the first line setting, and in relapse, with separate analysis of patients undergoing autologous stem cell transplantation. We assessed the response rates and toxicity profiles in both, IV and SC route of bortezomib administration. RESULTS: The response rates in both IV and SC arm were similar with overall response rate 71.7% vs 70.7%, complete remissions in 13.9% vs 8.6%, very good partial remissions in 30.8% vs 34.5% and partial remissions in 27% vs 27.6%. The most frequent grade ≥ 3 toxicities were anemia, thrombocytopenia and neutropenia, with no significant differences between IV and SC group. There were no significant differences in the rate of peripheral neuropathy (PN). PN of any grade was present in 48% in the IV arm and in 41% in the SC arm. PN grade ≥ 2 was present in 20% vs 18% and PN grade ≥ 3 was present in 6% vs 4%. CONCLUSIONS: We conclude that subcutaneous application of bortezomib has similar therapeutic outcomes and toxicity profile as intravenous route of application. In our cohort there was no difference in the incidence of PN, suggesting that PN is dose dependent and might be reduced by lower intensity schemes rather than by the route of administration.

10 years of experience with thalidomide in multiple myeloma patients: report of the Czech Myeloma Group.

We analyzed 1156 multiple myeloma (MM) patients treated with thalidomide. The overall response rate was 63.6%, with complete remission in 13.4%. Combined regimens had better outcomes than thalidomide plus dexamethasone or single agent thalidomide. Thalidomide was not able to overcome adverse cytogenetics. Superior results were seen in patients undergoing subsequent autologous stem cell transplantation. The rate of adverse events was low. Thalidomide has a strong potential to improve response and survival measures in patients with standard risk MM. Combined regimens should be used, with lower doses of thalidomide. High risk myelomas should be treated individually.

Efficacy and safety of administration of oral iron chelator deferiprone in patients with early myelodysplastic syndrome.

Forty-eight patients with early myelodysplastic syndrome (MDS) without excess of blasts, with average initial serum ferritin levels of 2739.5 µg/L (range 825-11287 µg/L), were treated with deferiprone (L1) in a daily dose of 40-90 mg/kg. Median duration of chelation treatment was 10.9 months (range 4-24 months). Chelation was effective (maintained or decreased iron stores) in 16 out of 22 patients (73%) with serum ferritin levels <2000 µg/L in contrast to only 12 out of 26 patients with serum ferritin levels >2000 µg/L. Combination of L1 with recombinant human erythropoietin (rHuEPO) (30-40 kU/week) resulted in effective chelation in five additional patients with serum ferritin levels >3000 µg/L. Incidence of adverse effects was comparable to that in thalassemic patients. Gastrointestinal symptoms represented the most frequent adverse effect of L1 therapy (37.5% of patients) that limited an effective escalation of the daily dose of the drug and led to discontinuation of the treatment for six patients. A decreased number of granulocytes was observed in five (13%) patients and agranulocytosis occurred in two patients (4%). Granulocyte counts were restored after cessation of L1 treatment and administration of granulocyte colony stimulating factor (G-CSF) in all but one patient. Administration of L1 in a daily dose of at least 75 mg/kg may represent an alternative approach in treatment of mild and moderate iron overload in MDS patients who cannot be treated with deferasirox (DFRA) or deferoxamine (DFO).

A novel fibrinogen variant--Liberec: dysfibrinogenaemia associated with gamma Tyr262Cys substitution.

OBJECTIVE: A 22-yr-old woman had abnormal preoperative coagulation test results and congenital dysfibrinogenaemia was suspected. PATIENTS AND METHODS: The patient from Liberec (Czech Republic) had a low fibrinogen plasma level as determined by Clauss method, normal fibrinogen level as determined by immunoturbidimetrical method, and prolonged thrombin time. To identify the genetic mutation responsible for this dysfibrinogen, genomic DNA extracted from the blood was analysed. Fibrin polymerisation measurement, kinetics of fibrinopeptide release, fibrinogen clottability measurement and scanning electron microscopy were performed. RESULTS: DNA sequencing showed the heterozygous fibrinogen gamma Y262C mutation. Kinetics of fibrinopeptide release was normal, however fibrin polymerisation was impaired. Fibrinogen clottability measurement showed that only about 45% molecules of fibrinogen are involved in the clot formation. Scanning electron microscopy revealed thicker fibres, which were significantly different from the normal control. CONCLUSION: A case of dysfibrinogenaemia, found by routine coagulation testing, was genetically identified as a novel fibrinogen variant (gamma Y262C) that has been named Liberec.