ALBERT

Description: To define the basis for faulty granulopoiesis in patients with severe congenital neutropenia (SCN), the expression of granulocyte colony-stimulating factor receptor (G-CSFR) in primitive myeloid progenitor cells and their responsiveness to hematopoietic factors were studied. Flow cytometric analysis of bone marrow cells based on the expression of CD34, Kit receptor, and G-CSFR demonstrated a reduced frequency of CD34+/Kit+/ G-CSFR+cells in patients with SCN. The granulocyte-macrophage colony formation of CD34+/Kit+/G-CSFR+ cells in patients was markedly decreased in response to G-CSF alone and to the combination of stem cell factor, the ligand for flk2/flt3, and IL-3 with or without G-CSF in serum-deprived semisolid culture. In contrast, no difference in the responsiveness of CD34+/Kit+/G-CSFR− cells was noted between patients with SCN and subjects without SCN. These results demonstrate that the presence of qualitative and quantitative abnormalities of primitive myeloid progenitor cells expressing G-CSFR may play an important role in the impairment of granulopoiesis in patients with SCN.

Description: BACKGROUND: The trial JACLS ALL-02 for treatment of childhood acute lymphoblastic leukemia (ALL) was designed to reduce acute and long-term toxicity in selected patient groups with favorable prognosis and to improve outcome in unfavorable-risk groups by treatment intensification. These aims were pursued through a refined stratification strategy using white blood cell count, age, immunophenotype, unfavorable genetic aberrations, and treatment response providing an excellent discrimination of risk groups. PATIENTS AND METHODS: Between April 2002 and March 2008, 1252 children with newly diagnosed de novo ALL with 1-18 years of age were enrolled to JACLS ALL-02 trial. Ph+ALL, mature B-ALL, and NK-leukemia were excluded. Patients with BCP-ALL were stratified into 3 groups: standard-risk (SR), high-risk (HR), extremely high-risk (ER), based on initial prednisolone (PSL) response and the modified National Cancer Institute(NCI) workshop criteria. Prednisolone poor response (PPR) was determined after 7 days of monotherapy with prednisone and one intrathecal dose of methotrexate. PSL good responders (PGR; 〈 1,000 blasts/microL) were divided into SR and HR according to the modified NCI workshop criteria by WBC 10K and age 10, and received conventional therapy. BCP-ALL with PPR (≥ 1,000 blasts/microL) or t(4;11), and acute mixed lineage leukemia/ acute unclassified leukemia were assigned to ER and received intensified post-induction therapy . Patients with T-ALL were treated by a specific protocol that was different from the protocol used for BCP-ALL. Bone marrow response was also evaluated in aspiration smears on day 15 and 33 of induction treatment, and those who had slow early bone marrow response, defined as an M3 marrow on day 15 or M2/3 marrow on day33, shifted to the higher risk and received augmented post-induction therapy. Cranial irradiation was restricted to patients with initial central nerve system involvement or T-ALL with high WBC (≥10K) at diagnosis. Alternatively, protracted TIT was given during induction, intensification and maintenance depending on the risk group (12 doses in SR/T and 15 in HR/ER). Slow early responders who had an M3 marrow on day 15 in ER/T or M2/3 marrow on day33 in any risk, underwent to stem cell transplantation (SCT). PPRs without slow early bone marrow response underwent to SCT only if a matched sibling donor was available. The probability of event-free survival (EFS) and overall survival were constructed using the Kaplan-Meier method. Events in the analysis of EFS included induction failure, death, relapse and secondary malignant neoplasm. All statistical analyses were done according to intent-to treat methods. RESULTS: Estimated 4-year EFS and OS for all 1252 patients was 83.7% (SE=1.1) and 90.3% (SE=0.89), slightly better in EFS than the former study (ALL-97; 79.3%, SE=1.7, p=0.054). The SR group (N=457, 37%) achieved excellent 4-year EFS of 90.4% (95%CI: 87.2, 92.7) and 4-year OS 97.3% (95.3, 98.5); in SR without slow early bone marrow response, patients with hyperdiploid and triple trisomy showed excellent 4-year EFS/OS of 100%. In the HR group (N=542, 43%), the estimated 4-year EFS and 4-year OS were 84.9% (81.5, 87.7) and 89.3% (86.3, 91.6), respectively; older age (≥ 6 years) was predictive for inferior OS (hazard ratio=1.14, p

Description: BACKGROUND: With current intensified chemotherapy, more than 70% of children with acute lymphoblastic leukemia (ALL) are curable. However, prognosis of the patients at higher risk has been unsatisfied. More appropriate risk assignment and innovative treatment is expected to be developed. We conducted a clinical trial of JACLS ALL-97 including multi-agent block therapy followed by hematopoietic stem cell transplantation (SCT) for the selected higher risk patients. PATIENTS AND METHODS: Between April 1997 and March 2002, 674 patients aged 1 to 15 years with newly diagnosed ALL (excluding mature B-cell ALL) were enrolled on the JACLS ALL-97 protocol. Excluding 75 T-ALL, 26 mixed lineage leukemia other than B-precursor ALL with myeloid markers, 9 acute unclassified leukemia and 1 B-precursor ALL with pretreatment, 563 patients with B-precursor ALL were eligible for this analysis. Treatment group was divided 5 groups according to the modified National Cancer Institute (NCI) workshop criteria. Standard risk (SR) and IR (intermediate risk) divided by WBC10 × 103 account for NCI-SR. High risk (HR) and ER (extremely high risk) divided by WBC 100 × 103 account for NCI-HR. The patients with ALL positive for Philadelphia chromosome and for translocation with chromosome11q23 were assigned to the highest risk group F. The patients in complete remission (CR) at day 35 with M2/M3 at the day 14 marrow were assigned to shift higher risk after induction therapy. Treatment of ALL-97 consists of early phase and maintenance phase. Early phase includes induction therapy, consolidation therapy, sanctuary therapy, and re-induction therapy for 19 to 26 weeks dependent on risk group. Early phase in IR/HR protocol is identical to the SR protocol except the addition of two doses of DNR and three doses of CPM. Maintenance phase contains standard MTX and MP with monthly VCR and PSL intensification for SR, and rotational therapy of a set of MTX and MP with a set of VCR, PSL, ASP, and (DNR or CPM) for IR/HR/ER/F. The IR protocol is identical to the HR protocol without cranial irradiation. Treatment duration is 24 months for any risk. The patients assigned ER and F were candidate for allogeneic stem cell transplantation by the end of early phase. Transplant procedures depended on the institute. RESULTS: Number of patients at each risk was 204 for SR, 158 for IR, 128 for HR, 36 for ER, 27 for Ph+ and 10 for 11q23. Six of them were treated with incorrect risk protocol. Thirty-four patients received SCT in first CR. Following the induction therapy, 550 of 564 patients (97.5%) achieved CR. 23 patients(8 in SR, 9 in IR, 4 in HR and 2 in ER, 4.4% of all) were shift to higher risk due to the findings of day 14 marrow. Five-year overall survival rate (OS) and event-free survival rate (EFS) for all patients was 90.6% and 77.0%, respectively. Five-year EFS for NCI-SR and HR was 81.6% and 67.6%, respectively. According to risk group, 5-year EFS for SR, IR, HR, ER, Ph+ ALL, and ALL with 11q23 were 86.6%, 77.0%, 71.9%, 68.7%, 40.7%, and 70.0%, respectively. 5-year OS for them were 94.0%, 93.9%, 92.1%, 83.8%, 55.6%, and 68.6%, respectively. CONCLUSIONS: By the risk-adapted therapy in the JACLS ALL-97 trial, high cure rate could be achieved for children with B-precursor ALL.

Description: T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LBL) account for most of the childhood T-lymphoid malignancy(LM). T-ALL is usually treated by the same protocol to the B-progenitor ALL. It is obvious that biologically, T-cell behaviors are different from those of B-progenitor cell, and cell origins are same among T-ALL and T-LBL. Thus we conducted a strategy initiating T-ALL specific protocol, differing from protocols for B-progenitor ALL. Furthermore, we indicated the same protocol to advanced T-LBL. The aims of this study were to evaluate the efficacy and safety of indicating the same protocol for childhood T-ALL and advanced T-LBL, and to reveal the prognostic factors of childhood T-LM. 70 eligibleT-ALL patients enrolled in the JACLS ALL-97 study between 1997-2001, and 32 eligible patients with stage III and IV T-LBL enrolled in the JACLS NHL-T98 trial between 1998-2002 were analyzed. Median age was 9y8m (2y~15y3m) for T-ALL and 11y11m (3y~15y4m) for T-LBL. Male/female ratio was 46/24, 26/6, respectively. Mediastinal mass was found in 31/70(44.3%) for T-ALL, 19/21(90.5%) for stageIII and 6/11(54.5%) for stageIV T-LBL. The treatment for 2 years consisted of the induction therapy (VCR, HD-MTX, CA, PSL, ASP), the 5-drug consolidation therapy A and B, both including high dose of ASP, and maintenance therapy with block-rotated treatment using drugs above. Complete remission(CR) at the end of induction therapy was obtained 65/70(92.9%) for T-ALL, 15/21(71.4%) for stage III and 10/11(90.9%) for stage IV T-NHL. 5-year overall survival(OAS) rate for T-ALL, stage III and stage IV T-LBL was 81.1%, 63.9% and 81.8%, respectively. 5-year event free survival (EFS) rate was 72.9%, 47.6% and 72.3%, respectively. Relapse after CR occurred in 12/65 with T-ALL, 6/15 with stage III and 1/10 with stage IV T-LBL. Single variant analysis revealed that there were no significant difference in OAS or EFS for T-ALL patients based on WBC, NCI index, but statistical difference in OAS or EFS based on age(older than 10y worse), the existence of mediastinal mass(absence, worse) In T-LBL, there were no statistical differences based on age, existence of mediastinal mass. Multivariate analysis revealed, for T-ALL and T-LBL patients as a whole, that age 〉 10 years was a risk factor in both OAS and EFS, absence of mediastinal mass and stage III T-LBL were risk factors in OAS. Our data shows that indicating same T-cell specific protocol, for T-ALL and advanced T-LBL has a potential to improve the prognosis of T-LM. The older age, and stage III T-LBL appeared as prognostic factors. Moreover, mediastinal mass with bone marrow involvement was a favorable factor for childhood T-LM. Although some risk factors were documented, it is needed to clarify unknown prognostic factors and develop the more effective, stratified T-cell specific protocols.

Description: With modern risk-adapted multi-agent chemotherapy, complete remission (CR) is obtained in the majority of children with acute lymphoblastic leukemia (ALL) and long-term survival free from disease can be expected in more than 70% of them. However, the prognosis of the patients without CR (induction failure; IF) has been dismal. We conducted a prospective study of F-protocol followed by a hematopoietic stem cell transplantation (SCT) in patients with IF. Purpose: To evaluate the efficacy and safety of the treatment strategy adopted in the JACLS ALL F-protocol. Patients and methods: Between April 1997 and March 2005, 1,254 patients with newly diagnosed ALL (excluding mature B-cell ALL) were enrolled on two consecutive JACLS ALL protocols (ALL-97 and ALL-02). Excluding induction death, 19 (1.6%) out of 1,207 patients with non-Ph+ ALL and 9 (30%) out of 30 patients with Ph+ ALL could not achieve CR following four- or five-drug induction chemotherapy. Among them, 25 patients in total were entered the study with guardian’s written consent. F-protocol consisted of the AML oriented re-induction chemotherapy (3 days of 8 mg/m2 MIT, 500 mg/m2 CA, and 40 mg/m2 PSL, followed by 3 days of 200 mg/m2 VP16, CA, and PSL a week later), four block consolidation therapy consisting of two alternative regimens A and B (A: HD-DEX, VP16, CA, MIT, B: HD-MTX, ASP, PSL, CA, THP-ADR) and maintenance therapy. Patients with CR were scheduled to receive SCT after the second consolidation therapy before the maintenance therapy. Transplant procedures depended on the institute. Results: Following the re-induction therapy, 15 of 16 patients with non-Ph+ ALL (93.8%) achieved CR and 13 (86.7%) of them had continued CR until 27th week of treatment (CCR), which was the expected limiting time of SCT. Eight of 11 patients receiving SCT at the first CCR are alive. Two of 13 patients with CCR did not receive SCT by a physician’s decision, and relapsed during maintenance therapy. However they are alive following SCT in second CR. Five-year overall survival rate (OS) and event free survival rate for all 16 cases was 53% and 32.8%, respectively. Estimated five-year OS for patients receiving SCT at the first CCR was 59.7%. On the other hand, only 3 of 9 patients with Ph+ ALL (33.3%) achieved CR. No patients without response to re-induction therapy could achieve CR by any subsequent chemotherapy, but one success with SCT. Among 3 patients attaining a CR with re-induction therapy, 2 could continue CR and underwent SCT. One is alive in CCR and the other deceased from TRM. The other patient, relapsed during consolidation therapy, underwent SCT with success. Five-year OS for all 9 patients with Ph+ ALL was 33.3%. Concerning about adverse events of F-protocol, there was only one non-hematological toxicity NCI-CTC grade 4, which was pancreatitis due to ASP. Conclusions: F-protocol could produce a high remission induction rate in non-Ph+ ALL, but not in Ph+ ALL. Improved outcome of non-Ph+ ALL patients with IF seemed to be obtained with F-protocol timely followed by SCT.

Description: [Background] According to the nation-wide retrospective study for pediatric leukemia phenotyping, immunological diagnostic committee of Japanese Pediatric Leukemia/Lymphoma Study Group (JPLSG) established diagnostic criteria and panel to pediatric hematological malignancies in 2008. Then Nation-wide standardized central immnophenotyping in Japan was started from 2011, and done in more than 2,500 cases by the end of 2014. Most cases were determined immunological diagnosis, but it was of note that we found 11 acute unclassified leukemia cases, including typical and atypical blastic plasmacytoid dendritic cell neoplasms (BPDCN). BPDCN is a rare subtype of leukemia/lymphoma, which has been categorized in the 2008 World Health Organization (WHO) classification of hematological diseases under acute myeloid leukemia and related precursor neoplasms. It was well known for high incidence of extra medullary regions. Most cases of BPDCN were found in elder people, so pediatric cases were extremely rare. We report here the characteristics of pediatric BPDCN cases, including clinical manifestations and peculiar immunophenotype. [Materials and Methods] Immunophenotyping was done on bone marrow (BM) aspiration samples according to diagnostic panel and criteria established by JPLSG immunological diagnostic committee. Immunophenotyping data from July 2011 to June 2015 were collected from JPLSG immunophenotyping centers and analyzed. BPDCN cases were screened by typically CD4+ 56+ HLA-DRhi profile. Other lineage markers such as CD7, CD34, CD13, CD33, CD36, CD64, CD123, and NG2 were also analyzed. As it is well known that existence of atypical phenotype in a substantial proportion, including absence of CD56 and/or CD4, immunophenotype data were prudently investigated and compared with 21 acute myelogenous leukemia (AML) presenting M5 characteristics in FAB criteria. [Result] Out of more than 2,500 cases, 4 cases were diagnosed as typical BPDCN (CD4+ 56+ HLA-DRhi), and 2 atypical BPDCN (1 CD56-, 1 CD4-) by immunophenotyping. All 6 cases presented leukemic dissemination, but only 4 typical cases indicated extra medullary regions. Gender ratio (M: F) was 3:1 and 0:2, and median age were 6.9 years (3.3 to 11.3) and 13.8 (12.8, 14.7) respectively. All 6 cases were negative for CD34 and CD13, and positive for NG2. CD123 was also positive in all (5/5) cases. CD33 and CD36 were positive in 5 cases respectively. It was of note that CD64, typical monocytic marker, was negative in all 6 cases although it was positive in all AML-M5 cases. All BPDCN cases could be distinguished with expression patterns of NG2, CD7, CD33, CD36 (positive) or CD13, CD64 (negative). Additionally, CD2 was positive in 3/6 cases, TdT was positive in 2/6 cases. CD117 was positive in 2 cases (1 typical, 1 atypical). [Discussion] BPDCN is a rare, clinically aggressive hematologic malignancy that most commonly manifests as cutaneous lesions with or without bone marrow involvement and leukemic dissemination. Diagnosis of BPDCN has been usually made by histopathologic examination with cutaneous lesions, which is typically positive for interleukin-3 receptor (CD123), blood dendritic cell antigen 2 (BDCA2)/CD303, and TCL-1. Morphologic and immunophenotypic studies were usually performed on BM and/or peripheral blood prior to histopathologic examination, however diagnosis with these examinations as BPDCN is not so easy because of the lack of morphological peculiarity or traditional lineage-specific markers. Treatments for BPDCN patients have been also inconsistent, because there are no prospective clinical trial data to define the optimal frontline treatment. AML-like or acute lymphoblastic leukemia (ALL)-like regimens have been used for induction therapy, as well as lymphoma-like regimens. The difficulty of BPDCN diagnosis might affect to choose inconsistent frontline therapy. Recently some reports documented ALL oriented therapy indicated more effectiveness to BPDCN, so the diagnosis should be made precisely to evaluate the treatment effectiveness. Here we indicated new diagnostic strategy by immunophenotyping with NG2, CD7, CD33, CD36, CD13, and CD64 as well as CD4, CD56 and HLA-DR. This approach contributes not only to select treatment regimen but also to investigate molecular pathogenesis such as whole exome sequence. Disclosures No relevant conflicts of interest to declare.

Description: [Background] Acute leukemia of ambiguous lineage is a very rare subtype defined by WHO 2008 classification. It is classified as mixed phenotype acute leukemia (MPAL), acute undifferentiated leukemia (AUL) and natural killer lymphoblastic leukemia. Basically, these category of leukemia consist of heterogenous pathogenesis. Determination of the lineage were usually decided by major lineage markers such as myeloperoxidase (MPO), CD19, and cytoplasmic CD3. However, more detailed immunophenotyping is necessary to confirm the cell lineages, especially in case of MPAL. Japanese pediatric leukemia/lymphoma study group (JPLSG) started nation-wide immunophenotyping with unified panel including more than 50 antigens for childhood hematological malignancy. Throughout this study, we found 32 acute leukemia of ambiguous lineage, including 3 AUL and 29 MPAL cases. MPAL cases were divided into several peculiar groups by our detailed phenotyping. We report here the characteristics of pediatric AUL/MPAL cases, including clinical manifestations and peculiar immunophenotype. [Result] In 3,229 case from January 2012 to December 2015, 32 cases were diagnosed as acute leukemia of ambiguous lineage. Gender ratio (M:F) was 18:14 and median age were 8.4 years (0.3 to 18.1) respectively. These cases were consisted of 3 AUL and 29 MPAL. According to detailed immunophenotyping, MPAL cases could be divided into 4 distinct clusters, (1) 7 T cell (T-) acute lymphoblastic leukemia (T-ALL)/acute myelogenous leukemia (AML)-M1 biphenotypic, (2) 4 early T-cell precursor (ETP)-like, (3) 8 B cell precursor (BCP-) ALL/Myelomonocytic bilineal, and (4) 10 BCP-ALL with MPO expression subtypes. T-ALL associated cases indicated relatively older age; (1) 12.3 and (2) 10.2 vs (3) 5.9 and (4) 7.5 respectively. 3 of (4) cases indicated characteristic genotypes; 1 minor bcr-abl, 1 major bcr-abl, and 1 AML1-ETO/Flt3-ITD. 4 out of 8 bilineal cases (3) were infantile ALL with MLL rearrangement, but other 4 older cases did not indicate MLL rearrangement. [Discussion] Acute leukemia of ambiguous lineage is a rare subtype of leukemia. According to WHO 2008 classification, it is further classified as MPAL, AUL and natural killer lymphoblastic leukemia. In this study, we evaluate 32 patients of acute leukemia of ambiguous lineage. It is of note that we could not identify no natural killer lymphoblastic leukemia in this childhood leukemia cohort. We also evaluate 29 MPAL cases, which showed 4 distinct subgroups. T-ALL/AML-M1 biphenotypic cases indicated relatively older age, usually diagnosed as AML-M1 with morphologic FAB classification, and received mostly myeloid oriented therapy. ETP-ALL like cases were positive for T cell antigens such as CD2 and/or CD7 and also some myeloid antigens but lacked cytoplasmic CD3 expression. BCP-ALL related cases were also divided into two groups, BCP-ALL/Myelomonocytic bilineal and BCP-ALL with MPO expression. Bilineal leukemia often found in infantile ALL with MLL gene rearrangement. In this study, we also found 4 non-infantile bilineal leukemia without MLL gene rearrangement. These cases occasionally cause lineage-switch relapse, so diagnosis of bilineal leukemia seems to be very significant. Recent studies showed EP300-ZNF384 fusion indicate CD10 negative or low BCP-ALL with MPO expression. Our cases also tended to indicate negative or low CD10 expression. In conclusion, we identified a spectrum of immunophenotype in MPAL patients. In childhood cases, most of MPAL cases were divided into 4 distinct categories. It must be useful information before examination of genetic abnormality. Disclosures No relevant conflicts of interest to declare.