Epidemiology, clinical picture and long-term outcomes of FIP1L1-PDGFRA-positive myeloid neoplasm with eosinophilia: Data from 151 patients

FIP1L1-PDGFRA-positive myeloid neoplasm with eosinophilia (F/P+ MN-eo) is a rare disease: robust epidemiological data are lacking and reported issues are scarce, of low sample-size and limited follow-up. Imatinib mesylate (IM) is highly efficient but no predictive factor of relapse after discontinuation has yet been identified. One hundred and fifty-one patients with F/P+ MN-eo (143 males; mean age at diagnosis 49 years; mean annual incidence: 0.18 case per million population) were included in this retrospective nationwide study involving all French laboratories who perform the search of F/P fusion gene (study period: 2003-2019). The main organs involved included the spleen (44%), skin (32%), lungs (30%), heart (19%) and central nervous system (9%). Serum vitamin B12 and tryptase levels were elevated in 74/79 (94%) and 45/57 (79%) patients, respectively, and none of the 31 patients initially treated with corticosteroids achieved complete hematologic remission. All 148 (98%) IM-treated patients achieved complete hematologic and molecular (when tested, n = 84) responses. Forty-six patients eventually discontinued IM, among whom 20 (57%) relapsed. In multivariate analysis, time to IM initiation (continuous HR: 1,01 [0.99-1,03]; P = .05) and duration of IM treatment (continuous HR: 0,97 [0,95-0,99]; P = .004) were independent factors of relapse after discontinuation of IM. After a mean follow-up of 80 (56) months, the 1, 5- and 10-year overall survival rates in IM-treated patients were 99%, 95% and 84% respectively. In F/P+ MN-eo, prompt initiation of IM and longer treatment durations may prevent relapses after discontinuation of IM.

Frontline treatment in multiple myeloma patients not eligible for stem-cell transplantation

Melphalan-prednisone-thalidomide (MPT) currently appears to be the treatment of choice for a large proportion of elderly patients ineligible for autologous stem-cell transplantation (ASCT). It seems certain that in the near future melphalan-prednisone-Velcade (MPV) and melphalan-prednisone-lenalidomide (MPR) will also be proved superior to melphalan-prednisone (MP), thus providing three therapeutic options (MPT, MPV and MPR) in this patient group with multiple myeloma (MM). These therapeutic options could lead to more personalized treatment approaches, based on patient comorbidities, as the three novel therapies have somewhat different toxicity profiles. MP would be appropriate for only a minority of patients with poor performance status and/or significant comorbidities, such as severe neuropathy or a contraindication to anticoagulants. Questions regarding the relative efficacy of melphalan-based regimens versus dexamethasone-based regimens (preferably with low-dose dexamethasone) will require randomized phase-III trials. More intensive approaches with new drug combinations or with the incorporation of polyethylene glycolated (PEGylated) liposomal doxorubicin will also require additional studies. Additionally, the important issue of maintenance treatment needs to be further investigated, especially in elderly patients.

An 18-case outbreak of drug-resistant Pseudomonas aeruginosa bacteriemia in hematology patients

We retrospectively identified an outbreak of 18 episodes of P. aeruginosa bacteriemia in 17 patients with hematologic malignancies in 2004. All strains were ticarcillin I/R, 77% ciprofloxacin I/R, 72% ceftazidime I/R, 72% amikacin I/R and 50% imipenem I/R. The outbreak was multiclonal. Colistin was employed for documented therapy in ten cases including seven in which it was the only active drug. Outcomes were resolution of infection in 12 out of 18 episodes (67%), and death in six cases, five (25%) of which were attributable to the infection. Colistin was useful even in highly resistant strains and the efficacy of antibacterial therapy was similar (57%)in bacteriemia due to strains only susceptible to colistin.

Imatinib and methylprednisolone alternated with chemotherapy improve the outcome of elderly patients with Philadelphia-positive acute lymphoblastic leukemia: results of the GRAALL AFR09 study

Acute lymphoblastic leukemia (ALL) in the elderly is characterized by its ominous prognosis. On the other hand, imatinib has demonstrated remarkable, although transient, activity in relapsed and refractory Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL), which prompted us to assess the use of imatinib in previously untreated elderly patients. ALL patients aged 55 years or older were given steroids during 1 week. Ph+ve cases were then offered a chemotherapy-based induction followed by a consolidation phase with imatinib and steroids during 2 months. Patients in complete response (CR) after consolidation were given 10 maintenance blocks of alternating chemotherapy, including two additional 2-month blocks of imatinib. Thirty patients were included in this study and are compared with 21 historical controls. Out of 29 assessable patients, 21 (72%, confidence interval (CI): 53-87%) were in CR after induction chemotherapy vs 6/21 (29%, CI: 11-52%) in controls (P=0.003). Five additional CRs were obtained after salvage with imatinib and four after salvage with additional chemotherapy in the control group. Overall survival (OS) is 66% at 1 year vs 43% in the control group (P=0.005). The 1-year relapse-free survival is 58 vs 11% (P=0.0003). The use of imatinib in elderly patients with Ph+ ALL is very likely to improve outcome, including OS.

Prognostic value of real-time quantitative PCR (RQ-PCR) in AML with t(8;21)

Despite the favorable prognosis of patients with acute myeloid leukemia (AML) with t(8;21)(q22;q22) translocation, relapses still occur in about 30% of the cases but no initial factors can strongly predict the risk of relapse. Several recent studies suggest that monitoring minimal residual disease (MRD) may identify patients at risk of relapse. We prospectively monitored AML1-ETO rearrangement by real-time quantitative PCR (RQ-PCR) in 21 patients uniformly treated in our center. Blood (PB) and bone marrow (BM) samples were collected during and after therapy. At diagnosis, levels of AML1-ETO transcript showed large variations and there was a trend for a higher relapse rate in patients with high pretreatment expression levels (P=0.065). After induction therapy, absolute transcript levels (below 10(-3), compared to Kasumi cell line), or a greater than 3 log decrease by comparison to diagnosis levels, were significant predictors of the absence of relapse (P=0.02 and P=0.02, respectively). MRD levels after consolidation therapy were also significant indicators of relapse (P=10(-5)). Comparison of BM and PB samples showed similar sensitivity for detecting AML1-ETO transcript. In conclusion, RQ-PCR appears to be an early predictive factor of the relapse risk in AML with t(8;21). PB samples can be used adequately to evaluate the level of MRD by this technique.