First-line second generation tyrosine kinase inhibitors in patients with newly diagnosed accelerated phase chronic myeloid leukemia.

Accelerated phase (AP) CML at onset and have poorer prognosis than CP-CML. We hypothesize that off-license use of second generation TKI (TKI2) as front-line therapy might counterbalance this poor prognosis, with limited toxicity. In "real-life" conditions, newly diagnosed patients meeting the ELN cytological criteria for AP-CML or harboring ACA and treated with first-line TKI2 were included in this retrospective multicenter observational study. We enrolled 69 patients [69.5 % male, median age 49.5 years, median follow-up 43.5 months], segregated into hematologic AP [HEM-AP (n = 32)] and cytogenetically defined AP [ACA-AP (n = 37)]. Hematologic parameters were worse in HEM-AP [spleen size (p = 0.014), PB basophils (p < .001), PB blasts (p < .001), PB blasts+promyelocytes (p < .001), low hemoglobin levels (p < .001)]. Dasatinib was initiated in 56 % patients in HEM-AP and in 27 % in ACA-AP, nilotinib in 44 % and 73 % respectively. Response and survival do not differ, regardless of the TKI2: 81 % vs 84.3 % patients achieved CHR, 88 % vs 84 % CCyR, 73 % vs 75 % MMR respectively. The estimated 5-year PFS 91.5 % (95%CI: 84.51-99.06 %) and 5-year OS 96.84 % (95%CI: 92.61-100 %). Only BM blasts (p < 0.001) and BM blasts+promyelocytes (p < 0.001) at diagnosis negatively influenced OS. TKI2 as front-line therapy in newly diagnosed AP-CML induce excellent responses and survival, and counterbalance the negative impact of advanced disease phase.

Prescription of Blood Lymphocyte Immunophenotyping in the Diagnosis of Lymphoid Neoplasms in Older Adults.

Lymphoid neoplasms are a heterogeneous group of lymphoid neoplastic diseases with multiple presentations, and varying prognoses. They are especially frequent in older patients (OPs) and the atypism of this frail elderly population can make the diagnostic process even more difficult. Blood lymphocyte immunophenotyping (BLI) is essential in rapid noninvasive diagnosis orientation and guides complementary investigations. To our knowledge, BLI prescription has never been evaluated in OPs. We hypothesized that, when there is a suspicion of lymphoid neoplasm in the geriatric population, a BLI is performed in view of various clinical or biological abnormalities. This study aimed to: (1) describe the characteristics of hospitalized OPs having undergone BLI for suspected lymphoid neoplasm, (2) identify the causes leading to BLI prescription, and (3) identify the most profitable criteria for BLI prescription. This was a descriptive retrospective study on 151 OPs aged ≥75 years who underwent BLI over a 2-year period. Regarding BLI prescriptions, eight had lymphocytosis, constituting the "lymphocytosis group" (LG+), while the 143 others had BLI prescribed for reasons other than lymphocytosis (LG-), mainly general weakness and anemia. In the LG-, we compared OPs with positive and negative BLI results. The criteria found to be profitable for BLI prescription were lymphadenopathy, splenomegaly, lymphocytosis, and thrombocytopenia. BLI identified circulating lymphoid neoplasms (positive BLI) in 21/151 OPs, mainly marginal zone lymphoma and chronic lymphocytic leukemia. In polymorbid OPs, as per our study population, the diagnostic and therapeutic complexity explained in part the sole use of indirect and minimally invasive diagnostic techniques such as BLI.

Positive quantitative PCR detecting Fusarium solani in a case of mixed invasive fungal disease due to Mucorales and Fusarium solani.

We present a case of invasive fungal co-infection in a young patient treated for an acute myeloid leukemia and having undergone a twice-haploid matched unrelated donor hematopoietic stem cell transplantation (HSCT) with two different donors. A mucormycosis diagnosis was made shortly after the patient's admission using imagery and specific Mucorales qPCR which was treated with liposomal amphotericin B and posaconazole. Twenty days later, a blood culture was positive for Fusarium solani, and disseminated cutaneous lesions appeared. The antifungal treatment was changed to liposomal amphotericin B and voriconazole. Thanks to a complete hematological reconstitution and despite a co-infection with two aggressive filamentous opportunistic fungi, the patient recovered. We took advantage of this clinical case to test a specific Fusarium solani qPCR, which proved to be promising when performed retrospectively on some of the patient samples.

Influence of alternative donor type on early survival after hematopoietic stem cell transplantation for acute myeloid leukemia lacking a sibling donor.

Allogeneic hematopoietic stem cell transplantation is the only potentially curative therapy for acute myeloid leukemia. In the absence of an HLA-matched related or unrelated donor (MRD or MUD), the best alternative donor source remains controversial. Umbilical cord blood and haploidentical donors offer a shorter delay from indication to transplantation. This retrospective multicentre study of a French registry compares overall survival in the 18 months following registration in the absence of a MRD between four types of donors. Between 2012 and 2016, 1302 patients were transplanted using MUD (control, n = 803), mismatched MUD (n = 219), umbilical cord blood (n = 153) and haploidentical (n = 127) donors. Multivariate analyses were conducted for overall survival after registration, after transplant, and transplant-related mortality. After adjustment for variables, the type of donor did not influence any of the three end points. Our results confirmed the significant negative impact of longer time between registration and transplant: HR = 1.04 [1.02-1.06] (p < 0.0001). This indicates a positive correlation between better survival and shorter registration-to-transplantation wait time. In the absence of a sibling donor, the alternative stem cell source does not impact early survival in acute myeloid leukemia patients. The minimization of registration-to-transplantation time should be considered when weighing the alternative donor options.

Evaluation of Residual Disease and TKI Duration Are Critical Predictive Factors for Molecular Recurrence after Stopping Imatinib First-line in Chronic Phase CML Patients.

PURPOSE: Tyrosine kinase inhibitor (TKI) discontinuation is an emerging goal in chronic myelogenous leukemia (CML) management and several studies have demonstrated the feasibility of safely stopping imatinib. A sustained deep molecular response on long-term TKI is critical prior to attempting treatment-free remission. Reproducible results from several studies reported recently, failed to identify robust and reproducible predictive factors for the selection of the best candidates for successful TKI cessation. PATIENTS AND METHODS: We conducted a prospective national phase II study evaluating the cessation of imatinib after at least 2 years of MR4.5 obtained on imatinib first-line in patients with chronic phase CML. RESULTS: A total of 218 patients with de novo chronic phase CML were involved in the study. The median follow-up after imatinib cessation was 23.5 (1-64) months, 2 patients died from unrelated causes, and 107 experienced a confirmed increase in BCR-ABL1 levels defined as molecular recurrence. The molecular recurrence-free survival was 52% [95% confidence interval (CI), 45%-59%] at 6 months, and 50% (95% CI, 43%-57%) at 24 months. Droplet digital PCR (ddPCR) was used to evaluate more accurately low levels of BCR-ABL1 in 175 of 218 patients at imatinib cessation. To apply positive BCR-ABL1/ABL1 ratios on the international scale (IS), a conversion factor was calculated for ddPCR and the significant cut-off point was established at 0.0023%IS. In a multivariate analysis, the duration of TKI (≥74.8 months) and ddPCR (≥0.0023%IS) were the two identified predictive factors of molecular recurrence, with P = 0.0366 (HR, 0.635; 95% CI, 0.415-0.972] and P = 0.008 (HR, 0.556; 95% CI, 0.360-0.858), respectively. CONCLUSIONS: We conclude that the duration of TKI and residual leukemic cell load as determined by ddPCR are key factors for predicting successful treatment-free remission for patients with de novo chronic phase CML.See related commentary by Yan et al., p. 6561.

Altered thymic CD4+ T-cell recovery after allogeneic hematopoietic stem cell transplantation is critical for nocardiosis.

PURPOSE OF THE STUDY: Nocardia affects immunocompromised human host exhibiting an altered cell-mediated immunity. Infectious risk after allogeneic hematopoietic cell transplantation (AHCT) is significantly correlated to the recovery status of donor-derived immune system, especially CD4+ T-cells reconstitution and thymopoiesis. The purpose of this paper is to highlight a lack of cell-mediated immunity recovery for patients presenting a nocardiosis compared to a control cohort. PATIENTS AND METHODS: This is a case control retrospective monocentric study. We retrospectively analyzed a monocentric cohort of 15 cases of nocardiosis after AHCT and we explored the degree of patients' immunosuppression by phenotyping circulating lymphoid subpopulations, including NK cells, CD8+ T-cells, CD4+ T-cells and CD19+ B-cells. We focused on CD4+ T-cell subsets to appreciate thymic output, especially on naive CD4+ T-cells (NTE, CD45RA+/RO- CD4+ T-cells) and recent thymic emigrants (RTE, CD4+CD45RA+/RO-/CD31+). Infected patients were paired with a control cohort of patients with identical transplantation characteristics screened on hematological disease, AHCT conditioning, primary graft-versus-host disease (GHVD) prophylaxis, graft type, sex, age, and season at the AHCT and data concerning immunological reconstitution were compared. RESULTS: At onset of nocardiosis, circulating lymphocytes and CD4+ T-cells means count were respectively 730/µL and 162/µL. CD8+ T-cells, CD56+ NK cells and CD19+ B-cells means count were respectively 362/µL, 160/µL, 112/µL. CD4+ T-cells subpopulations, naïve CD4+ T-cells production was impaired with NTE and RTE means count at 26/µL and 11/µL respectively. Comparison between nocardiosis cohort and control cohort over time highlight significant lower cellular count for lymphocytes, CD4+ T-cells, NTE and RTE with p = 0.001, p < 0.001, p < 0.001, p < 0.001 respectively. CONCLUSION: Immune recovery monitoring follow-up after AHCT is of particular importance to identify patients susceptible to develop Nocardiosis. Efficient microbiological investigations toward Nocardia such PCR should be used in case of compatible clinical presentation.

CML Hematopoietic Stem Cells Expressing IL1RAP Can Be Targeted by Chimeric Antigen Receptor-Engineered T Cells.

Chronic myeloid leukemia (CML) is a chronic disease resulting in myeloid cell expansion through expression of the BCR-ABL1 fusion transcript. Tyrosine kinase inhibitors (TKI) have significantly increased survival of patients with CML, and deep responders may consider stopping the treatment. However, more than 50% of patients relapse and restart TKI, subsequently suffering unknown toxicity. Because CML is a model immune system-sensitive disease, we hypothesize that chimeric antigen receptor (CAR) T cells targeting IL1 receptor-associated protein (IL1RAP) in quiescent CML stem cells may offer an opportunity for a permanent cure. In this study, we produced and molecularly characterized a specific monoclonal anti-IL1RAP antibody from which fragment antigen-binding nucleotide coding sequences were cloned as a single chain into a lentiviral backbone and secured with the suicide gene iCASP9/rimiducid system. Our CAR T-cell therapy exhibited cytotoxicity against both leukemic stem cells and, to a lesser extent, monocytes expressing IL1RAP, with no apparent effect on the hematopoietic system, including CD34+ stem cells. This suggests IL1RAP as a tumor-associated antigen for immunotherapy cell targeting. IL1RAP CAR T cells were activated in the presence of IL1RAP+ cell lines or primary CML cells, resulting in secretion of proinflammatory cytokines and specifically killing in vitro and in a xenograft murine model. Overall, we demonstrate the proof of concept of a CAR T-cell immunotherapy approach in the context of CML that is applicable for young patients and primary TKI-resistant, intolerant, or allograft candidate patients. SIGNIFICANCE: These findings present the first characterization and proof of concept of a chimeric antigen receptor directed against IL1RAP expressed by leukemic stem cells in the context of CML.

SALL4 oncogene is an immunogenic antigen presented in various HLA-DR contexts.

Purpose: To investigate the immunoprevalence of SALL4-derived peptides in healthy volunteers and cancer patients. Experimental Design: A multistep approach including prediction algorithms was used to design in silico SALL4-derived peptides theoretically able to bind on common HLA-DR and HLA-A/B molecules. The presence of T-cell responses after a long term T-cell assay (28 days) against SALL4 was monitored in 14 healthy donors and the presence of T-cell responses after a short term T-cell assay (10 days) was monitored in 67 cancer patients using IFN-γ ELISPOT assay. A T-cell clone specific for the immunoprevalent A18 K-derived peptide was isolated, characterized and used as a tool to characterize the natural processing of A18 K. Results: A SALL4 specific T-cell repertoire was present in healthy donors (8/14) and cancer patients (29/67) after short term T-cell assay. We further identified two immunoprevalant SALL4-derived peptides, R18 A and A18 K, which bind MHC-class II. In parallel, an A18 K specific Th1 clone recognized monocyte derived Dendritic Cell (moDC) loaded with SALL4 containing cell lysate. The level of IFN-γ secreted by specific T-cell clone was greater in presence of moDC loaded with SALL4 containing cell lysate (49.23 ± 14.02%) than with moDC alone (18.03 ± 3.072%) (p = 0.0477) Conclusion: These results show for the first time immunogenicity of SALL4 oncogenic protein-derived peptides, especially A18 K and R18 A peptides and make them potential targets for personalized medicine. Thus, SALL4 possess major characteristics of a tumor antigen.

Cytotect®CP as salvage therapy in patients with CMV infection following allogeneic hematopoietic cell transplantation: a multicenter retrospective study.

Cytomegalovirus is one of the main contributing factors to high mortality rates in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT). The main factors of treatment failure are both drug resistance and intolerance. In some cases, Cytotect®CP CMV-hyperimmune globulin is used as salvage therapy. This study aims to investigate the safety and efficacy of Cytotect®CP as a salvage therapy in patients with CMV infection after allo-HCT. Twenty-three consecutive patients received Cytotect®CP for CMV infection after prior CMV therapy. At the time of Cytotect®CP introduction, 17 patients (74%) had developed acute GVHD and 15 patients (64%) were receiving steroid treatment; Cytotect®CP was used as monotherapy (n = 7) and in combination (n = 16). Overall, response was observed in 18 patients (78%) with a median time of 15 days (range: 3-51). Of the 18 responders, 4 experienced CMV reactivation, while 5 responders died within 100 days of beginning treatment. Of these 5 deaths, 4 were due to causes unrelated to CMV. Estimated 100-day OS from the introduction of Cytotect®CP was 69.6%. No statistically significant difference was observed in 100-day OS between responders and non-responders (73.7% vs 50.0%, p = 0.258). Cytotect®CP as salvage therapy is effective and well-tolerated. Given its safety profile, early treatment use should be considered.

Impact of body-surface area on patients' outcome in younger adults with acute myeloid leukemia.

OBJECTIVES: Anthracyclines and cytarabine are cornerstones for intensive chemotherapy in acute myeloid leukemia (AML). The goals of this study were to comprehensively assess deviations from theoretical doses and the impact of body-surface area (BSA) on patients' characteristics, physicians' strategy, dose adjustment, and clinical outcome. METHODS: The GOELAMS 2001 phase III trial included 823 AML patients below 60 years of age. In the course of treatment, anthropomorphic parameters and chemotherapy doses were prospectively registered. RESULTS: Very high BSA (≥2.15 m2 ) was the factor most significantly associated with the physician's decision to reduce chemotherapy doses during induction and postremission therapy. Despite similar AML characteristics and therapeutic strategies, the very high BSA group exhibited a significantly worse survival (5-years OS of 27%) compared to the low (BSA≤1.5 m2 ), intermediate (1.5 m2

The p16(INK4A)/pRb pathway and telomerase activity define a subgroup of Ph+ adult Acute Lymphoblastic Leukemia associated with inferior outcome.

Adult Acute Lymphoblastic Leukemia (ALL) therapies have been improved by pediatric-like approaches. However, treatment failures and relapses are common and new markers are needed to identify patients with poor prognosis in prospective trials. The p16(INK4A)/CDK4-6/pRb pathway and telomerase activity, which are implicated in cell activation and aging, were analyzed to identify new prognostic markers. Proteins of the p16(INK4A)/CDK4-6/pRb pathway and telomerase activity were analyzed in 123 adult B-cell precursor (BCP) ALL cases included in the GRAALL/GRAAPH trials. We found a significantly increased expression of p16(INK4A) in BCP-ALLs with MLL rearrangement. Telomerase activity was significantly lower in Philadelphia chromosome-negative/IKAROS-deleted (BCR-ABL1(-)/IKAROS(del)) cases compared to Philadelphia chromosome-positive (BCR-ABL1+) BCP-ALLs. In BCR-ABL1+ ALLs, high CDK4 expression, phosphorylated pRb (p-pRb) and telomerase activity were significantly associated with a shorter disease-free survival (DFS) and event-free survival (EFS). Enhanced p16(INK4A) expression was only related to a significantly shorter DFS. In vitro analyses of normal stimulated lymphocytes after short- and long-term cultures demonstrated that the observed protein variations of poor prognosis in BCR-ABL1+ ALLs may be related to cell activation but not to cell aging. For these patients, our findings argue for the development of therapeutic strategies including the addition of new lymphocyte activation inhibitors to current treatments.

Erratum to: New CD20 alternative splice variants: molecular identification and differential expression within hematological B cell malignancies.

[This corrects the article DOI: 10.1186/s40164-016-0036-3.].

New CD20 alternative splice variants: molecular identification and differential expression within hematological B cell malignancies.

BACKGROUND: CD20 is a B cell lineage-specific marker expressed by normal and leukemic B cells and targeted by several antibody immunotherapies. We have previously shown that the protein from a CD20 mRNA splice variant (D393-CD20) is expressed at various levels in leukemic B cells or lymphoma B cells but not in resting, sorted B cells from the peripheral blood of healthy donors. RESULTS: Western blot (WB) analysis of B malignancy primary samples showed additional CD20 signals. Deep molecular PCR analysis revealed four new sequences corresponding to in-frame CD20 splice variants (D657-CD20, D618-CD20, D480-CD20, and D177-CD20) matching the length of WB signals. We demonstrated that the cell spliceosome machinery can process ex vivo D480-, D657-, and D618-CD20 transcript variants by involving canonical sites associated with cryptic splice sites. Results of specific and quantitative RT-PCR assays showed that these CD20 splice variants are differentially expressed in B malignancies. Moreover, Epstein-Barr virus (EBV) transformation modified the CD20 splicing profile and mainly increased the D393-CD20 variant transcripts. Finally, investigation of three cohorts of chronic lymphocytic leukemia (CLL) patients showed that the total CD20 splice variant expression was higher in a stage B and C sample collection compared to routinely collected CLL samples or relapsed refractory stage A, B, or C CLL. CONCLUSION: The involvement of these newly discovered alternative CD20 transcript variants in EBV transformation makes them interesting molecular indicators, as does their association with oncogenesis rather than non-oncogenic B cell diseases, differential expression in B cell malignancies, and correlation with CLL stage and some predictive CLL markers. This potential should be investigated in further studies.

Posaconazole prophylaxis in neutropenic patients with hematological malignancies: limits in clinical practice.

Posaconazole (PSZ) is being used for prophylaxis in hematological patients who are at high risk for invasive fungal disease (IFD), but absorption limitations have been reported. Our objective was to assess both the feasibility and the efficacy of PSZ prophylaxis in clinical practice. From March 2010 to September 2010, all patients admitted to our unit for chemotherapy for acute leukemia or hematopoietic stem cell transplantation received optimized PSZ prophylaxis 200 mg four times daily with cola soda. PSZ trough concentrations (Cmin) were monitored at days 5, 7, 14, and 21. The incidence of IFDs was determined and compared to that of a historical control group. Thirty-five consecutive patients were prospectively included. PSZ prophylaxis was interrupted for 29% of them at day 14 and 51% of them at day 21. The main limitations were impracticality of oral feeding (29%) and occurrence of suspected IFDs (23%). PSZ median Cmin were 0.47, 0.40, 0.24, 0.36 µg/mL at days 5, 7, 14, and 21, respectively. Eighty percent of patient results were lower than the target Cmin of 0.5 µg/ml on day 14, the higher-risk period associated with neutropenia. Four probable breakthrough IFDs (11%) were diagnosed in 2010; no clear association between PSZ Cmin and occurrence of infection was observed. The incidence of IFDs was unchanged (historical control group: 9.7%; P = 0.72). Implementation of systematic PSZ prophylaxis did not significantly decrease the incidence of IFDs at our center. PSZ interruptions related to mucositis and too low Cmin were the main limitations to its use.

A successful renal transplantation for renal failure after dasatinib-induced thrombotic thrombocytopenic purpura in a patient with imatinib-resistant chronic myelogenous leukaemia on nilotinib.

Second-generation tyrosine kinase inhibitors (TKI2) often induce molecular remission, and prolonged survival with a better tolerance in imatinib-resistant chronic myelogenous leukaemia (CML) patients. We report the case of a CML in first chronic phase who was diagnosed in August 2003 in a young 24 year-old Caucasian woman. Our patient received first imatinib and then dasatinib and nilotinib. Imatinib was well tolerated and she developed TTP/HUS on dasatinib without documented evolution of CML and finally obtained MR5.0 with nilotinib and without any side effect. This case also illustrates the absence of cross-resistance and side-effects between the different TKIs and the feasibility of kidney transplantation associated with a nilotinib treatment of CML allowing a continuing MR5.0 and no further side effects.

Early matched sibling hematopoietic cell transplantation for adult AML in first remission using an age-adapted strategy: long-term results of a prospective GOELAMS study.

The LAM2001 phase 3 trial, involving 832 patients with acute myeloid leukemia (AML; median: 46 years) proposed HLA-identical sibling allograft HSCT for all patients with an identified donor. The trial compared reduced-intensity conditioning (RIC) for patients older than 50 years of age (N = 47) and myeloablative conditioning for younger patients (N = 117). BM HSCT was performed in the younger patients, while the older ones received a consolidation course, followed by peripheral blood allo-HSCT using RIC. The incidence of grade II-IV acute GVHD, was 51.9% (95% confidence interval [CI]: 42.1-61.8) and 11.3% (1.6-21.2) after myeloablative or RIC, respectively (P < .0001) and that of chronic GVHD 45.8% (95% CI: 34.8-56.7) and 41.7% (24.7-58.6; NS). Cumulative incidence of nonrelapse mortality at 108 months was 15.8% (95% CI: 9.8-23.2) for myeloablative, and 6.5% (0.2-16.2) for RIC (NS). CI of relapse at 108 months was 21.7% (95% CI: 13.9-28.6) and 28.6% (16.5-43.4; NS). Overall survival at 108 months was 63.4% (95% CI: 54.6-72.2) and 65.8% (52.2-72.2), respectively, after myeloablative or RIC (NS). RIC peripheral blood stem cell allo-HSCT is prospectively feasible for patients between the ages of 51 and 60 years without excess of relapse or nonrelapse mortality, and compares favorably with myeloablative marrow allo-HSCT proposed to younger patients.

Systematic donor blood qualification by flow cytometry would have been able to avoid CLL-type MBL transmission after unrelated hematopoietic stem cell transplantation.

The current screening for eligibility of unrelated volunteer marrow donors comprises a complete clinical check-up, a blood CBC and serum protein immunoelectrophoresis. This allows to eliminate acute leukemias, myeloproliferative and myelodysplastic disorders, myelomas and MGUS. To date, the risk of transmission of chronic lymphocytic leukemia (CLL) disease is only evaluated by the clinical evaluation and CBC. We report here the case of a CLL-type MBL disease occurring in a 12-year-old boy after unrelated BMT. Deep biological investigations, as Immunophenotyping, cytogenetic and molecular biology allow us to determine the donor origin of the CLL clone. In 2010, 14.2% donor (105/737) for unrelated hematopoietic stem cell transplantation were over 45y. It is currently estimated (USA) that 1 in 210 men and women will be diagnosed with CLL during their lifetime. Given the long asymptomatic phase of CLL, this raises the case for a detection strategy analog to that used for MGUS and myeloma through serum protein electrophoresis. This case-report, to our knowledge, of a CLL-type MBL unrelated donor-to-recipient transmission through BMT raises ethical and practical questions, such as the proper information about disease transmission risk. The cost-effectiveness of a systematic peripheral blood Immunophenotyping in donors elder than 40y at time of stem cell donation should be evaluated.

Intrathecal liposomal cytarabine (lipoCIT) administration in patients with leukemic or lymphomatous meningitis: efficacy and long-term safety in a single institution.

BACKGROUND: There is limited information regarding the efficacy and long term safety of intrathecal injection of liposomal cytarabine in leukemic or lymphomatous meningitis. DESIGN AND METHODS: We studied 20 consecutive HIV-negative patients with leukemic or lymphomatous meningitis who were treated with intrathecal liposomal cytarabine between 2004 and 2007. We focused on efficacy and on any late effects of the drug. RESULTS: Twenty patients who received intrathecal liposomal cytarabine injection as part of their treatment; of these, 9 were alive and in complete remission at the end of the study. Median survival from the time of the first injection was 22.7 months (range, 0.5 to 64 months). Short-term toxicity related to intrathecal of liposomal cytarabine was observed in 2 cases; headache in 1 case and regressive facial palsy and diplopy in 1 case. Long-term toxicity was seen in 2 cases; clinical symptoms were urinary and fecal dysfunction with confusion in 1 case, and urinary dysfunction in 1 case. Both patients had been heavily pre-treated with neurotoxic drugs and neuraxis irradiation. CONCLUSION: In our experience, intrathecal liposomal cytarabine injections were convenient in the management of leukemic and lymphomatous meningitis, and can lead to long-term survival. Although neurotoxicity was rare, clinicians should exercise caution when retreatment is required in relapsing patients.

CD304 is preferentially expressed on a subset of B-lineage acute lymphoblastic leukemia and represents a novel marker for minimal residual disease detection by flow cytometry.

Minimal residual disease (MRD) has emerged as a major prognostic factor for monitoring patients with B-lineage acute lymphoblastic leukemia (B-ALL). The quantification of MRD by flow cytometry (FC) is based on the identification of a leukemia-associated phenotype (LAP). Because phenotypic switch is common during treatment, multiple LAPs must be available and used for MRD detection over time. We evaluated the potential usefulness of CD304 as a new marker for monitoring MRD. CD304 was expressed in 48% of B-ALL (24/50) with discriminative fluorescence intensity compared with CD304-negative normal B-cell precursors (n = 15). The sensitivity of CD304-based MRD detection reached 10(-4), as with some of established LAPs. The stability of CD304 expression evaluated during therapy and at relapse confirms the usefulness of this marker for MRD quantification. Finally, CD304 was repeatedly expressed in patients with TEL-AML1 gene rearrangement, which warrants further investigation on its potential relevance as a prognosis marker or therapeutic target.