BCR-ABL1 Doubling-Times and Halving-Times May Predict CML Response to Tyrosine Kinase Inhibitors.

In Chronic Myeloid Leukemia (CML), successful treatment requires accurate molecular monitoring to evaluate disease response and provide timely interventions for patients failing to achieve the desired outcomes. We wanted to determine whether measuring BCR-ABL1 mRNA doubling-times (DTs) could distinguish inconsequential rises in the oncogene's expression from resistance to tyrosine kinase inhibitors (TKIs). Thus, we retrospectively examined BCR-ABL1 evolution in 305 chronic-phase CML patients receiving imatinib mesylate (IM) as a first line treatment. Patients were subdivided in two groups: those with a confirmed rise in BCR-ABL1 transcripts without MR3.0 loss and those failing IM. We found that the DTs of the former patients were significantly longer than those of patients developing IM resistance (57.80 vs. 41.45 days, p = 0.0114). Interestingly, the DT values of individuals failing second-generation (2G) TKIs after developing IM resistance were considerably shorter than those observed at the time of IM failure (27.20 vs. 41.45 days; p = 0.0035). We next wanted to establish if decreases in BCR-ABL1 transcripts would identify subjects likely to obtain deep molecular responses. We therefore analyzed the BCR-ABL1 halving-times (HTs) of a different cohort comprising 174 individuals receiving IM in first line and observed that, regardless of the time point selected for our analyses (6, 12, or 18 months), HTs were significantly shorter in subjects achieving superior molecular responses (p = 0.002 at 6 months; p < 0.001 at 12 months; p = 0.0099 at 18 months). Moreover, 50 patients receiving 2G TKIs as first line therapy and obtaining an MR3.0 (after 6 months; p = 0.003) or an MR4.0 (after 12 months; p = 0.019) displayed significantly shorter HTs than individuals lacking these molecular responses. Our findings suggest that BCR-ABL1 DTs and HTs are reliable tools to, respectively, identify subjects in MR3.0 that are failing their assigned TKI or to recognize patients likely to achieve deep molecular responses that should be considered for treatment discontinuation.

Rapid decline of Philadelphia-positive metaphases after nilotinib treatment in a CML patient expressing a rare e14a3 BCR-ABL1 fusion transcript: A case report.

We report a case of chronic myeloid leukemia in a 52-year-old male expressing a rare e14a3 BCR-ABL1 fusion transcript. Cytogenetic analysis showed the t(9;22) translocation and multiplex RT-PCR detected an atypical fragment of approximately 230 base pairs. Using two primers recognizing exon 10 of BCR and exon 4 of ABL1, a larger PCR product was identified, cloned, sequenced and defined as an e14a3 BCR-ABL1 rearrangement. The patient was treated with nilotinib and monitored measuring cytogenetic and hematological parameters, while BCR-ABL1 transcripts were surveyed by conventional and semi-nested PCR. The patient achieved a complete hematologic response after two months of treatment followed by a complete cytogenetic remission two months later. Furthermore, PCR and semi-nested PCR failed to detect the e14a3 BCR-ABL1 mRNA after 15 and 21 months of nilotinib, respectively.

Efficacy of Nilotinib in a CML Patient Expressing the Three-way Complex Variant Translocation t(2;9;22).

BACKGROUND/AIM: Chronic myelogenous leukemia (CML) is characterized by the presence of the Philadelphia chromosome, resulting from the reciprocal translocation involving chromosomes 9 and 22. About 5-10% of newly diagnosed patients in chronic-phase (CP) CML show complex additional chromosomal aberrations (ACA), that may involve one or more chromosomes in addition to 9 and 22. Data concerning the prognostic significance of ACA in CP-CML subjects at diagnosis are controversial. Furthermore, there is no evidence showing that selection of imatinib (IM) or second-generation tyrosine kinase inhibitors (2G-TKI) would be of benefit for these patients. CASE REPORT: We report the three-way complex variant translocation t(2;9;22) in a CP-CML patient. Conventional cytogenetic analysis was employed to identify the ACA. Multiplex reverse transcription-PCR was used to identify the BCR-ABL1 transcript and its levels were measured using quantitative real-time-PCR. This rare ACA t(2;9;22) in our young patient displayed primary resistance to IM, but was responsive to second-line treatment with nilotinib. CONCLUSION: CP-CML patients exhibiting this rare aberration at diagnosis may benefit from a 2G-TKI therapy compared to IM.

Efficacy of Dasatinib in a Very Elderly CML Patient Expressing a Rare E13a3 Bcr-Abl1 Fusion Transcript: A Case Report.

We report the case of an 89-year-old male diagnosed with chronic-phase CML and expressing a rare e13a3 BCR-ABL1 fusion transcript. His cytogenetic analysis showed the t(9;22) translocation generating the Philadelphia chromosome (Ph), with a multiplex RT-PCR detecting an atypical fragment. Using two primers complementary to exon 10 of BCR and exon 4 of ABL1, a larger PCR product was observed, where after Sanger sequencing, an e13a3 BCR-ABL1 transcript was revealed. Given the diagnosis, the patient received 100 mg of dasatinib every other day and was then monitored by measuring both hematological and cytogenetic parameters, while his BCR-ABL1 transcripts were examined by PCR and semi-nested-PCR. According to the 2013 European Leukemia Network criteria, after six months of dasatinib the patient's response was classified as warning as he displayed 20% of Philadelphia-positive metaphases. Sequencing of the ABL1 catalytic domain did not detect point mutations. A complete cytogenetic response was achieved after one year of dasatinib. However, semi-nested-PCR confirmed the presence of the e13a3 BCR-ABL1 fusion transcript that has persisted up to the latest follow-up visit.

Clinical Implications of Discordant Early Molecular Responses in CML Patients Treated with Imatinib.

A reduction in BCR-ABL1/ABL1IS transcript levels to <10% after 3 months or <1% after 6 months of tyrosine kinase inhibitor therapy are associated with superior clinical outcomes in chronic myeloid leukemia (CML) patients. In this study, we investigated the reliability of multiple BCR-ABL1 thresholds in predicting treatment outcomes for 184 subjects diagnosed with CML and treated with standard-dose imatinib mesylate (IM). With a median follow-up of 61 months, patients with concordant BCR-ABL1/ABL1IS transcripts below the defined thresholds (10% at 3 months and 1% at 6 months) displayed significantly superior rates of event-free survival (86.1% vs. 26.6%) and deep molecular response (≥ MR4; 71.5% vs. 16.1%) compared to individuals with BCR-ABL1/ABL1IS levels above these defined thresholds. We then analyzed the outcomes of subjects displaying discordant molecular transcripts at 3- and 6-month time points. Among these patients, those with BCR-ABL1/ABL1IS values >10% at 3 months but <1% at 6 months fared significantly better than individuals with BCR-ABL1/ABL1IS <10% at 3 months but >1% at 6 months (event-free survival 68.2% vs. 32.7%; p < 0.001). Likewise, subjects with BCR-ABL1/ABL1IS at 3 months >10% but <1% at 6 months showed a higher cumulative incidence of MR4 compared to patients with BCR-ABL1/ABL1IS <10% at 3 months but >1% at 6 months (75% vs. 18.2%; p < 0.001). Finally, lower BCR-ABL1/GUSIS transcripts at diagnosis were associated with BCR-ABL1/ABL1IS values <1% at 6 months (p < 0.001). Our data suggest that when assessing early molecular responses to therapy, the 6-month BCR-ABL1/ABL1IS level displays a superior prognostic value compared to the 3-month measurement in patients with discordant oncogenic transcripts at these two pivotal time points.

Colony-Forming Cell Assay Detecting the Co-Expression of JAK2V617F and BCR-ABL1 in the Same Clone: A Case Report.

BCR-ABL1-negative myeloproliferative disorders and chronic myeloid leukaemia are haematologic malignancies characterised by single and mutually exclusive genetic alterations. Nevertheless, several patients co-expressing the JAK2V617F mutation and the BCR-ABL1 transcript have been described in the literature. We report the case of a 61-year-old male who presented with an essential thrombocythaemia phenotype and had a subsequent diagnosis of chronic phase chronic myeloid leukaemia. Colony-forming assays demonstrated the coexistence of 2 different haematopoietic clones: one was positive for the JAK2V617F mutation and the other co-expressed both JAK2V617F and the BCR-ABL1 fusion gene. No colonies displayed the BCR-ABL1 transcript alone. These findings indicate that the JAK2V617F mutation was the founding genetic alteration of the disease, followed by the acquisition of the BCR-ABL1 chimeric oncogene. Our data support the hypothesis that a heterozygous JAK2V617F clone may have favoured the bi-clonal nature of this myeloproliferative disorder, generating clones harbouring a second transforming genetic event.

Cost-effectiveness of on-demand plerixafor added to chemotherapy and granulocyte-colony stimulating factor for peripheral blood stem cell mobilization in multiple myeloma.

We here report final results of a phase II/III prospective study that evaluated in Multiple Myeloma the use of on-demand plerixafor (PLX) added to mobilizing chemotherapy for patients showing predictive signs of mobilization failure. A total of 111 patients with MM were registered, all received cyclophosphamide 4 g/m2 and granulocyte colony-stimulating factor (G-CSF). Overall, a successful CD34+ cell mobilization was achieved in 97.2% (108/111) of patients. Minimum harvest (≥2.0 × 106 CD34+ cells/kg) was achieved in 97.2% (108/111) and optimal harvest success (≥4.0 × 106 CD34+ cells/kg) was achieved in 84.6% (94/111). Multivariate analysis showed that patients who received on-demand PLX treatment had significantly higher likelihoods of successfully achieving both the minimal (p = .006) and optimal harvest (p = .05) in respect to a historical control group mobilized without any PLX. The incremental cost-effectiveness ratio, for each 1% increase in probability of achieving a successful minimal harvest, was €40.6 per patient.

Low-dose lenalidomide plus cytarabine in very elderly, unfit acute myeloid leukemia patients: Final result of a phase II study.

Outcome for elderly patients with acute myeloid leukemia (AML) is extremely poor. Intensive induction chemotherapy is often unsuitable. Sixty-six newly diagnosed AML patients (median age: 76years), ineligible for standard therapy, were consecutively treated with low-dose lenalidomide (10mg/day orally, days 1-21) plus 10mg/m2 low-dose cytarabine, subcutaneously, twice a day (days 1-15) every six weeks, up to 6 cycles. Complete remission (CR) rate was 36.3% according to intention-to-treat. Responding patients had a longer median overall survival than non-responders (517 vs. 70days, P<0.001). The achievement of CR was not predicted by bone marrow blast count, cytogenetics, molecular markers, prior MDS, white blood cell count. Conversely, by studying the global gene expression profile, we identified a molecular signature, including 309 genes associated with clinical response (CR versus no CR). Based on the expression of a minimal set of 16 genes, we developed an algorithm to predict treatment response, that was successfully validated by showing an overall accuracy of 88%. We met the primary endpoint of the study, by beating the estimated successful CR rate (P1) fixed at 30%. Moreover, CR induced by this 2-drug combo was efficiently predicted by genetic profiling, identifying a biomarker that warrants validation in independent series.

Cancer patients requiring interruption of long-term warfarin because of surgery or chemotherapy induced thrombocytopenia: the use of fixed sub-therapeutic doses of low-molecular weight heparin.

No data are available regarding the management of cancer patients requiring interruption of long-term vitamin-K antagonist (VKA) therapy. For this purpose, we tested the efficacy and safety of fixed doses of low-molecular weight heparin (LMWH) in substitution of VKA because of invasive procedures or chemotherapy-induced thrombocytopenia. In cancer patients on VKA, therapy was discontinued 5 ± 1 days before surgery or chemotherapy. Heparin was given at prophylactic dosage in patients at low risk and at fixed subtherapeutic doses (3,800 or 4,000 UI anti-FXa, b.i.d.) in those at high-risk for thrombosis. LMWH was reinitiated 12 hr after surgery and VKA the day after. In patients receiving chemotherapy, LMWH was reinitiated 12/24 hr after obtaining a stable platelet count ≥ 30,000 mmc(3) and VKA after a stable platelet count ≥ 50,000 mmc(3) . Thromboembolism and major bleeding events were recorded from the time of VKA suspension to 30 ± 2 days postprocedure or until the next chemotherapy. Overall, 156 patients (56.4% at low risk and 43.5% at high risk for thrombosis) were enrolled; 34.6% underwent major surgery, 40.4% nonmajor surgery, and 25% chemotherapy. Thrombotic events occurred in five patients [3.2%, 95% confidence interval (CI): 1.41-7.27], four belonging to the high-risk and one to the low-risk group. Major bleeding occurred in five patients (3.2%, 95 CI: 1.41-7.27), all belonging to the high-risk group (three during major surgery and two during chemotherapy). In conclusion, LMWH given at fixed subtherapeutic is a feasible and relatively safe approach for bridging therapy in cancer patients on long-term VKA.

Safety of plasma-derived protein C for treating disseminated intravascular coagulation in adult patients with active cancer.

Cancer-related disseminated intravascular coagulation (DIC) is a life-threatening condition for which no effective treatment is currently available. Protein C (PC), a modulator of coagulation as well as the inflammatory system, has been successfully tested (in its activated recombinant form [a-rPC]) in sepsis-related coagulopathy, but with an increased risk for major bleeding. Plasma-derived PC (pd-PC) is more suitable than a-rPC in patients at high risk from bleeding due to its self-limiting process. We carried out a single-arm study evaluating the role of pd-PC in adult cancer patients with overt DIC. Over a period of 3 years, we treated 19 patients with overt DIC and a PC plasma concentration <50%; all received PC concentrate (Ceprotin(®), Baxter) for 72 hr in adjusted doses to restore normal PC values (70-120%). Blood coagulation, haematological tests, and the DIC score were recorded after 12, 24, 48 hr, 7 and 10 days, while clinical outcomes (bleeding, thrombosis and mortality) were recorded up to 28 days. Within 48 hr of starting pd-PC therapy, laboratory tests as well as the DIC score improved in all patients. At 28-days follow-up, no bleeding or thrombosis was observed. This is the first study to investigate the use of pd- PC for treatment of cancer-related overt DIC.