Masashi Sawa

BMI-1 is Highly Expressed in M0-Subtype Acute Myeloid Leukemia

Recent studies have suggested that one of the polycomb group genes,BMI- 1, has an important role in the maintenance of normal and leukemic stem cells by repressing theINK4a/ARF locus. Here, we quantitatively examinedBMI- 1 expression level in samples from patients with acute myeloid leukemia (AML) and other hematologic malignancies. Moderate to highBMI- 1 expression was detected in AML patients, and theBMI- 1 expression levels in AML samples were significantly higher than in normal bone marrow controls(P =.0011). Specimens of French-American-British classification subtype M0 showed higher relative expression of the BMI-1 transcript (median, 390.2 x 10-3) than the other subtypes (median, 139.0 x 10-3)(P <.0001). Leukemia other than AML showed low to moderate expression. INK4a-ARF transcript expression tended to be inverse proportion to that of BMI-1. In an M0 patient with a high BMI-1 transcript level, the INK4a-ARF transcript level fell promptly and maintained a low value after the patient achieved complete remission. These results indicated that a subgroup of M0 patients has a high expression level of polycomb group geneBMI- 1, which may contribute to leukemogenesis.

Short-term methotrexate could reduce early immune reactions and improve outcomes in umbilical cord blood transplantation for adults

Post transplant immune disorders are problematic in cord blood transplantation (CBT) for adult patients, and optimal prophylaxis has not been established. We investigated whether intensive graft-versus-host disease (GVHD) prophylaxis using short-term methotrexate (MTX) has a prognostic impact on CBT. Post-CBT immune reactions were classified according to time course as pre-engraftment immune reaction (PIR), engraftment syndrome (ES) or acute GVHD. Between March 2001 and November 2005, a total of 77 patients underwent CBT at eight transplantation centers. Median age was 48 years (range, 18–69 years). Preparative regimens comprised myeloablative (n=31) or reduced-intensity (n=46). Acute GVHD prophylaxis included cyclosporine alone (n=23), tacrolimus alone (n=12), cyclosporine plus MTX (n=17), tacrolimus plus short-term MTX (n=23) or cyclosporine plus methylprednisolone (n=2). Cumulative incidences of PIR, ES and grade II–IV GVHD were 36, 12 and 23%, respectively. Short-term MTX exerted significant favorable effects on post-CBT immune reactions (hazard ratio, 0.55; 95% confidence interval (95% CI), 0.31–0.98; P=0.04) in multivariate analysis. Overall survival rates for patients with and without short-term MTX at day 180 were 59% (95% CI, 42–73%) and 16% (95% CI, 6.6–30%) (P=0.0001), respectively. Short-term MTX could offer one optimal regimen to reduce immune reactions and improve outcomes in CBT.

Monitoring of Hepatitis B Virus (HBV) DNA and Risk of HBV Reactivation in B-Cell Lymphoma: A Prospective Observational Study

BACKGROUND There is no standard management of reactivation of hepatitis B virus (HBV) infection in HBV-resolved patients without hepatitis B surface antigen (HBsAg), but with antibodies against hepatitis B core antigen and/or antibodies against HBsAg (anti-HBs). METHODS We conducted a prospective observational study to evaluate the occurrence of HBV reactivation by serial monthly monitoring of HBV DNA and to establish preemptive therapy guided by this monitoring in B-cell non-Hodgkin lymphoma (B-NHL) treated with rituximab plus corticosteroid-containing chemotherapy (R-steroid-chemo). The primary endpoint was the incidence of HBV reactivation defined as quantifiable HBV DNA levels of ≥ 11 IU/mL. RESULTS With a median HBV DNA follow-up of 562 days, HBV reactivation was observed in 21 of the 269 analyzed patients. The incidence of HBV reactivation at 1.5 years was 8.3% (95% confidence interval, 5.5-12.4). No hepatitis due to HBV reactivation was observed in patients who received antiviral treatment when HBV DNA levels were between 11 and 432 IU/mL. An anti-HBs titer of <10 mIU/mL and detectable HBV DNA remaining below the level of quantification at baseline were independent risk factors for HBV reactivation (hazard ratio, 20.6 and 56.2, respectively; P < .001). Even in 6 patients with a rapid increase of HBV due to mutations, the monthly HBV DNA monitoring was effective at preventing HBV-related hepatitis. CONCLUSIONS Monthly monitoring of HBV DNA is useful for preventing HBV reactivation-related hepatitis among B-NHL patients with resolved HBV infection following R-steroid-chemo (UMIN000001299).

Clinicopathological manifestations and treatment of intestinal transplant-associated microangiopathy

Intestinal transplant-associated microangiopathy (i-TAM) is an important complication after allogeneic hematopoietic SCT. From 1997 to 2006, 87 of 886 patients with diarrhea after transplantation received colonoscopic biopsy. i-TAM, GVHD and CMV colitis were diagnosed histopathologically. The median duration from transplantation to the onset of diarrhea was 32 days (range: 9–130 days) and that from the onset of diarrhea to biopsy was 12 days (range: 0–74 days). The median maximal amount of diarrhea was 2 l/day (range: 130–5600 ml/day). Histopathological diagnosis included i-TAM (n=80), GVHD (n=26), CMV colitis (n=17) and nonspecific findings (n=2) with overlapping. Among 80 patients with i-TAM, abdominal pain was a major symptom, and only 11 patients fulfilled the proposed criteria for systemic TAM. Non-relapse mortality (NRM) among patients without resolution of diarrhea was 72% and i-TAM comprised 57% of NRM. NRM was 25% among patients without intensified immunosuppression, but was 52, 79 and 100% among those with intensified immunosuppression before diarrhea, after diarrhea, and before and after diarrhea, respectively. In conclusion, i-TAM is a major complication presenting massive refractory diarrhea and abdominal pain, which causes NRM. Avoiding intensified immunosuppression that damages vascular endothelium until the resolution of i-TAM may improve transplant outcome.

Tamibarotene As Maintenance Therapy for Acute Promyelocytic Leukemia: Results From a Randomized Controlled Trial

PURPOSE The introduction of all-trans-retinoic acid (ATRA) has significantly improved outcomes for acute promyelocytic leukemia (APL), although a subset of patients still suffer relapse. The purpose of this study was to evaluate the role of maintenance therapy with the synthetic retinoid tamibarotene in APL. PATIENTS AND METHODS Patients with newly diagnosed APL in molecular remission at the end of consolidation therapy were randomly assigned to receive ATRA or tamibarotene, both orally, for 14 days every 3 months for up to 2 years. RESULTS A total of 347 patients were enrolled. Of the 344 eligible patients, 319 (93%) achieved complete remission. After completing three courses of consolidation therapy, 269 patients underwent maintenance random assignment. The relapse-free survival (RFS) rate at 4 years was 84% for the ATRA arm and 91% for the tamibarotene arm (hazard ratio [HR], 0.54; 95% CI, 0.26 to 1.13). When the analysis was restricted to 52 high-risk patients with an initial WBC count ≥ 10.0 × 10(9)/L, the intergroup difference was statistically significant, with 4-year RFS rates of 58% for the ATRA arm and 87% for the tamibarotene arm (HR, 0.26; 95% CI, 0.07 to 0.95). For patients with non-high-risk disease, the HR was 0.82 (95% CI, 0.32 to 2.01). The test for interaction between treatment effects and these subgroups resulted in P = .075. Both treatments were generally well tolerated. CONCLUSION In this trial, no difference was detected between ATRA and tamibarotene for maintenance therapy. In an exploratory analysis, there was a suggestion of improved efficacy of tamibarotene in high-risk patients, but this requires further study.

Irrespective of CD34 expression, lineage-committed cell fraction reconstitutes and re-establishes transformed Philadelphia chromosome-positive leukemia in NOD / SCID / IL-2Rγc−/− mice

(Cancer Sci 2010; 101: 631–638)

Hematopoietic stem cell transplantation for acute promyelocytic leukemia in second or third complete remission: a retrospective analysis in the Nagoya Blood and Marrow Transplantation Group

Acute promyelocytic leukemia (APL) is the most curable subtype of acute myeloid leukemia. Second complete remission (CR2) can be easily achieved with several therapeutic options even after relapse. However, the optimal strategy to treat APL in CR2 is still controversial. We retrospectively compared the outcome of autologous (auto) and allogeneic (allo) hematopoietic stem cell transplantation (HSCT) for patients with APL in CR2 or CR3. Fifteen patients received auto and 13 received allo HSCT between 1999 and 2004 at eight hospitals belonging to the Nagoya Blood and Marrow Transplantation Group. Four-year disease-free survival (DFS) and overall survival (OS) for autografted patients were 68.9 and 75.8%, whereas those for allografted patients were 46.2 (P = 0.350) and 46.2% (P = 0.185), respectively. Three autografted patients and one allografted patient relapsed, and one autografted patient and five allografted patients died without leukemia relapse. Among 14 autografted patients who were evaluated for MRD with molecular analysis, relapse occurred in one with positive MRD (n = 2) and two with negative MRD (n = 12). These data suggest that auto HSCT is very effective for APL in CR2 or CR3, and may be preferable to allo HSCT for a portion of patients. Prospective studies are required to define the role of auto HSCT in the treatment of relapsed APL.

Comparison of transplant outcomes from matched sibling bone marrow or peripheral blood stem cell and unrelated cord blood in patients 50 years or older.

Older recipient and donor age were associated with higher incidences of severe graft‐versus‐host disease (GVHD) and mortality after allogeneic hematopoietic stem cell transplantation from matched sibling donors (MSDs) and matched unrelated donors. Since a lower incidence of severe GVHD is advantageous in unrelated cord blood transplantation (CBT), a higher incidence of GVHD using older MSDs could be overcome using cord blood for older patients. We retrospectively analyzed Japanese registration data of 2,091 patients with acute myeloid leukemia, acute lymphoblastic leukemia (ALL), and myelodysplastic syndrome aged 50 years or older who underwent MSD bone marrow transplantation (BMT) (n = 319), MSD peripheral blood stem cell transplantation (PBSCT) (n = 462), or unrelated CBT (n = 1,310) between 2007 and 2012. Median age of MSD was 56 (range, 38–74) years. Compared with CBT, the risk of developing extensive chronic GVHD was higher after BMT (hazard ratio [HR], 2.00; P = 0.001) or PBSCT (HR, 2.38; P < 0.001), and transplant‐related mortality was lower after BMT (HR, 0.61; P < 0.001) or PBSCT (HR, 0.63; P < 0.001). Relapse rates were not significant difference between three groups. Although overall mortality was lower after BMT (HR, 0.67; P < 0.001) or PBSCT (HR, 0.75; P = 0.002) compared with CBT, the rates of a composite endpoint of GVHD‐free, relapse‐free survival (GRFS) were not significant difference between three groups. These data showed that MSDs remain the best donor source for older patients, but CBT led to similar GRFS to BMT and PBSCT. Am. J. Hematol. 91:E284–E292, 2016.

Ki-67 is a strong predictor of central nervous system relapse in patients with mantle cell lymphoma (MCL)

BACKGROUND Central nervous system (CNS) relapse is an uncommon but challenging complication in patients with mantle cell lymphoma (MCL). Survival after CNS relapse is extremely poor. Identification of high-risk populations is therefore critical in determining patients who might be candidates for a prophylactic approach. PATIENTS AND METHODS A total of 608 patients (median age, 67 years; range 22-92) with MCL newly diagnosed between 1994 and 2012 were evaluated. Pretreatment characteristics and treatment regimens were evaluated for their association with CNS relapse by competing risk regression analysis. RESULTS None of the patients received intrathecal prophylaxis. Overall, 33 patients (5.4%) experienced CNS relapse during a median follow-up of 42.7 months. Median time from diagnosis to CNS relapse was 20.3 months (range: 2.2-141.3 months). Three-year cumulative incidence of CNS relapse was 5.6% [95% confidence interval (95% CI) 3.7% to 8.0%]. Univariate analysis revealed several risk factors including blastoid variant, leukemic presentation, high-risk MCL International Prognostic Index and high Ki-67 (proliferation marker). Multivariate analyses revealed that Ki-67 ≥ 30 was the only significant risk factor for CNS relapse (hazard ratio: 6.0, 95% CI 1.9-19.4, P = 0.003). Two-year cumulative incidence of CNS relapse in patients with Ki-67 ≥ 30 was 25.4% (95% CI 13.5-39.1), while that in the patients with Ki-67 < 30 was 1.6% (95% CI 0.4-4.2). None of the treatment modalities, including rituximab, high-dose cytarabine, high-dose methotrexate or consolidative autologous stem-cell transplant, were associated with a lower incidence of CNS relapse. Survival after CNS relapse was poor, with median survival time of 8.3 months. There was no significant difference in the survival by the site of CNS involvement.

Impact of low-dose TBI on outcomes of reduced intensity conditioning allogeneic hematopoietic stem cell transplantation for AML

Impact of low-dose TBI on outcomes of reduced intensity conditioning allogeneic hematopoietic stem cell transplantation for AML