Hiroki Yokoyama

Potential efficacy of the oral histone deacetylase inhibitor vorinostat in a phase I trial in follicular and mantle cell lymphoma

Vorinostat (suberoylanilide hydroxamic acid, SAHA, Zolinza) is a histone deacetylase inhibitor with clinical activity in cutaneous T‐cell lymphoma (CTCL). A phase I trial of oral vorinostat was conducted in Japanese patients with malignant lymphoma. Vorinostat 100 or 200 mg was administered twice daily for 14 consecutive days followed by a 1‐week rest interval. Of 10 patients enrolled, four had follicular lymphoma (FL), two mantle cell lymphoma (MCL), two diffuse large B‐cell lymphoma, and two CTCL (median age, 60 years; median number of prior regimens, 3). Vorinostat was well tolerated up to 200 mg with only one of six patients developing a dose‐limiting toxicity (DLT; Grade 3 anorexia/hypokalemia). Common Grade 3 events were reversible neutropenia (30%), thrombocytopenia, and hypermagnesemia (20% each). The median number of treatment cycles was five (range, 1–36); two patients were continuing treatment. The overall response rate was 40%, with two complete responses/unconfirmed (CRu) and one partial response among FL patients and one CRu among MCL patients. One FL patient maintained CRu for 18.0 months. The median time to achieve CRu among the three patients was 8 months. These data suggest that further investigations of vorinostat in non‐Hodgkin lymphoma, focusing on FL and MCL, are warranted. (Cancer Sci 2009)

Phase I and pharmacokinetic study of bendamustine hydrochloride in relapsed or refractory indolent B-cell non-Hodgkin lymphoma and mantle cell lymphoma

Bendamustine is a cytotoxic agent with a novel mechanism of action. This phase I, dose‐escalation study evaluated the safety, tolerability, efficacy, and pharmacokinetics of bendamustine in Japanese patients with relapsed/refractory indolent B‐cell non‐Hodgkin lymphoma (B‐NHL) or mantle cell lymphoma (MCL) without major organ dysfunction. Bendamustine 90 or 120 mg/m2 (dose escalation) was administered intravenously over 60 min on days 1 and 2 every 3 weeks for up to three cycles. Nine patients (eight indolent B‐NHL and one MCL) received per‐protocol treatment, three at 90 mg/m2 and six at 120 mg/m2. No dose‐limiting toxicities were observed; thus, the maximum‐tolerated dose was not reached. Grade 3/4 hematologic toxicities were neutropenia (33%) and leukopenia (33%). Non‐hematologic toxicities were grade 1/2 and included gastrointestinal events and fatigue. Peak plasma concentrations of bendamustine occurred near the end of infusion in both dose groups and were equivalent to therapeutic concentrations observed in vitro. Bendamustine was rapidly eliminated, with a mean elimination half‐life (t1/2) of 29 min. Plasma concentrations of active metabolites M3 and M4 were approximately 4 and <1% of the plasma concentration of the parent molecule, with t1/2 of 42 and 33 min, respectively. Two unconfirmed complete responses and six partial responses were observed for an overall response rate (ORR) of 89%. The recommended dose for this schedule in phase II trials is 120 mg/m2. The acceptable safety profile and high ORR warrant further investigation of bendamustine in relapsed or refractory indolent B‐NHL and MCL. (ClinicalTrials.gov ID: NCT00389051). (Cancer Sci 2010)

Impact of T Cell Chimerism on Clinical Outcome in 117 Patients Who Underwent Allogeneic Stem Cell Transplantation with a Busulfan-Containing Reduced-Intensity Conditioning Regimen

Within the concept of reduced-intensity stem cell transplantation (RIST) there is a wide range of different regimens used, and little information is available on the clinical impact of chimerism status in patients conditioned with a busulfan-containing regimen. Therefore, we retrospectively reviewed lineage-specific chimerism and the subsequent clinical outcome in 117 patients (median age, 55 years; range: 29-68) who underwent busulfan-containing RIST. The conditioning regimen consisted of busulfan (oral 8 mg/kg or i.v. 6.4 mg/kg) and fludarabine (180 mg/m(2), n = 64) or cladribine (0.66 mg/kg, n = 53), with or without 2-4 Gy total-body irridiation (TBI) (n = 26) or antihuman T-lymphocyte immunoglobulin (ATG; 5-10 mg/kg; n = 31). Chimerism was evaluated with peripheral blood samples taken on days 30, 60, and 90 after transplantation by polymerase chain reaction (PCR)-based amplification of polymorphic short tandem repeat regions. The median follow-up of surviving patients was 1039 days (153-2535). The percent donor-chimerism was significantly higher in granulocyte than T cell fraction throughout the entire course, and the median (mean) values were, respectively, 100% (96%) versus 95% (83%), 100% (98%) versus 100% (89%), and 100% (98%) versus 100% (91%) at days 30, 60, and 90 after RIST. In a multivariate analysis, having received <2 types of chemotherapy regimens before RIST was the only factor that was significantly associated with low donor T cell chimerism (<60%) at day 30 (hazard ratio [HR]: 6.1; 95% confidence interval [CI], 2.1-18.4; P < .01). The median percentage of donor T cell chimerism at day 30 was 9% (0%-63%) in 5 patients who experienced graft failure, which was significantly lower than that (97%; 15%-100%) in the rest of the patients (P < .01). No correlation was found between the kinetics of T cell chimerism and the occurrence of acute or chronic GVHD (aGVHD, cGVHD). The stem cell source and the addition of TBI or ATG were not associated with the degree of T cell chimerism, overall survival (OS) or event-free survival (EFS). In a Cox proportional hazard model, low donor T cell chimerism of <60% at day 30 was associated with both poor OS (HR: 2.2; 95% CI, 1.1-4.5; P = .02) and EFS (HR: 2.0; 95% CI, 1.1-3.8; P = .02). In conclusion, we found that 43% of the patients retained mixed donor T cell chimerism (<90% donor) at day 30, whereas 92% achieved complete chimerism in granulocyte fraction. Low donor T cell chimerism of <60% at day 30 may predict a poor outcome, and a prospective study to examine the value of early intervention based on chimerism data is warranted.

Donor Lymphocyte Infusion for the Treatment of Relapsed Acute Myeloid Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation: A Retrospective Analysis by the Adult Acute Myeloid Leukemia Working Group of the Japan Society for Hematopoietic Cell Transplantation

Because the efficacy of donor lymphocyte infusion (DLI) for acute myeloid leukemia (AML) relapse after allogeneic hematopoietic stem cell transplantation (HSCT) remains uncertain, especially in the Asian population, a nationwide registry study was retrospectively performed by the Adult AML Working Group of the Japan Society for Hematopoietic Cell Transplantation to identify the factors affecting the patient survival after DLI. Among 143 adult AML patients who received DLI for the treatment of first hematological relapse after HSCT, the overall survival rates at 1 year, 2 years, and 5 years were 32% ± 4%, 17% ± 3%, and 7% ± 3%, respectively. Complete remission (CR) at the time of DLI, which was obtained in 8% of the patients, was the strongest predictive factor for survival after DLI. Therefore, long-term survival after DLI was achieved almost exclusively in patients who successfully achieved a CR before DLI, indicating the limited efficacy of DLI in a minority of patients.

Prognosis of acute myeloid leukemia harboring monosomal karyotype in patients treated with or without allogeneic hematopoietic cell transplantation after achieving complete remission

To evaluate the prognostic impact of monosomal karyotype on post-remission outcome in acute myeloid leukemia, we retrospectively analyzed 2,099 patients who had achieved complete remission. Monosomal karyotype was noted in 73 patients (4%). Of these, the probability of overall survival from first complete remission was 14% at four years, which was significantly lower than that reported in patients without monosomal karyotype, primarily due to a high relapse rate (86%). Monosomal karyotype remained significantly associated with worse overall survival among patients with unfavorable cytogenetics or complex karyotype, and even in patients who underwent allogeneic hematopoietic cell transplantation during first complete remission. These findings confirm that monosomal karyotype has a significantly adverse effect on post-remission outcome in patients with acute myeloid leukemia treated with and without allogeneic hematopoietic cell transplantation in first complete remission, emphasizing the need for the development of alternative therapies for this patient population.

Outcome of 93 patients with relapse or progression following allogeneic hematopoietic cell transplantation

Relapse/progression after allogeneic hematopoietic cell transplantation (allo‐HCT) remains the major cause of treatment failure. In this study, the subsequent clinical outcome was overviewed in 292 patients with leukemia/myelodysplastic syndrome who received allo‐HCT. Among them, 93 (32%) showed relapse/progression. Cohort 1 was chosen to receive no interventions with curative intent (n = 25). Cohort 2 received reinduction chemotherapy and/or donor lymphocyte infusion (n = 48), and Cohort 3 underwent a second allo‐HCT (n = 20). Sixty‐three patients received reinduction chemotherapy, and 27 (43%) achieved subsequent complete remission (CR). The incidence of nonrelapse mortality (NRM) was similar among the three cohorts (4, 15, and 5%). The 1‐year overall survival (OS) after relapse was significantly better in patients with a second HCT (58%) than in others (14%, Cohorts 1 and 2; P <.001). However, the 2‐year OS did not differ between the two groups, which suggests that it is difficult to maintain CR after the second HCT. Multivariate analysis showed that reinduction chemotherapy, CR after intervention, second HCT, and longer time to post‐transplant relapse were associated with improved survival. In conclusion, for patients with relapse after allo‐HCT, successful reinduction chemotherapy and a second HCT may be effective for prolonging survival without excessive NRM. However, effective measures to prevent disease progression after a second HCT clearly need to be developed. Am. J. Hematol. 2009.

The indolent course and high incidence of t(14;18) in primary duodenal follicular lymphoma

BACKGROUND Information on the clinical behavior of the recently proposed primary duodenal follicular lymphoma (DFL) is limited. PATIENTS AND METHODS Demographic data, signs, symptoms, disease stage, and treatment of the patients diagnosed in National Cancer Center Hospital from 1999 to 2007 were collected and analyzed. RESULTS Twenty-seven patients were studied. Nineteen patients were asymptomatic at the time of diagnosis. Twenty patients had stage I disease. The histological grade was 1 or 2 in 26 patients. IgH/BCL2 fusion was shown in 20 of the examined 24 cases (83%). Fourteen patients received therapy upon diagnosis (local radiotherapy in 2 patients and chemotherapy in 12 including rituximab therapy), their response rate was 85%, and the estimated progression-free survival (PFS) rate at 3 years was 70%. One patient developed histological transformation. The other 13 patients were followed up; their estimated PFS rate at 3 years was 74%. Five among six cases responded to treatment even after progressive disease. All 27 patients have survived with a median follow-up time of 47.9 months. CONCLUSIONS The majority of primary DFL patients have a localized tumor of low-grade histology and are positive for t(14;18). Watchful waiting might be an alternative approach for its indolent course; however, further studies are warranted.

Stromal cells in bone marrow play important roles in pro-inflammatory cytokine secretion causing fever following bortezomib administration in patients with multiple myeloma

Bortezomib blocks the activation of nuclear factor-κB-mediated pro-inflammatory cytokines, however, systemic inflammatory symptoms following bortezomib administration have been reported, although their mechanisms remain elusive. Serum samples were obtained from five patients, who participated in a phase I/II study of Japanese patients with relapsed or refractory multiple myeloma (MM), and developed cyclic fever following bortezomib administration, to measure cytokine levels. Significant correlations between interleukin (IL)-6 or interferon (IFN)-γ and the body temperature were observed in two patients each. Furthermore, we found that IL-6 elevation was not observed after the addition of bortezomib to any examined MM cells alone, but was noted in a case of bone marrow stromal cells (BMSCs) of macrophage origin alone or co-cultured with MM cells. Similarly, a marked increase in IFN-γ levels was induced by adding bortezomib to BMSCs of fibroblast origin. Although this investigation was a preliminary study with a small number of patients, our results suggested that pro-inflammatory cytokines causing bortezomib-associated fever were secreted from BMSCs rather than MM cells.

Rapid progression and unusual premortal diagnosis of mucormycosis in patients with hematologic malignancies: analysis of eight patients

Mucormycosis is a rare but emerging group of life-threatening opportunistic mycoses. We described experience of eight patients who developed mucormycosis. These patients had developed hematologic malignancies, and none achieved complete remission. Six of the eight patients presented with neutropenia, five received corticosteroid, and four had concomitant hyperglycemia. The most frequent physical finding was fever, and five patients complained of facial pain, headache, or chest pain. Four patients presented with concomitant bacterial infection, pulmonary aspergillosis, or intestinal candidiasis. Premortal diagnosis of mucormycosis was made in only one patient. Postmortem biopsy or autopsy was the diagnostic tool for the other patients. Although patients who were treated with amphotericin B survived longer than those treated with micafungin or voriconazole, all patients died due to the progression of mucormycosis. Estimated median survival was 23 days. Premortal diagnosis was rarely achieved as biopsy of infected tissues was the only diagnostic tool, and four patients who revealed dual infection were diagnosed with aspergillosis or bacterial infections. In patients with a high risk of mucormycosis presenting with pain and uncontrollable fever, mucormycosis should be included in the differential diagnosis. High dosages of liposomal amphotericin B should be given and surgical debridement should be performed promptly in cases highly suggestive of mucormycosis.

Epstein-Barr Virus-associated Lymphoproliferative Disorder with Encephalitis Following Anti-thymocyte Globulin for Aplastic Anemia Resolved with Rituximab Therapy: A Case Report and Literature Review

Epstein-Barr virus (EBV)-associated lymphoproliferative disorders (LPDs) sometimes occur following Anti-thymocyte globulin (ATG) administration for allogenic stem cell transplantation but are rare in aplastic anemia (AA) patients. A 55-year-old woman with AA following ATG developed refractory fever and was diagnosed with EBV-LPD. She was successfully treated with weekly rituximab monotherapy; however, she developed EBV encephalitis. She was admitted to the intensive care unit and finally recovered from unconsciousness. EBV-LPD should be considered after ATG for AA when symptoms appear. Because EBV-LPD following ATG for AA can rapidly progress, weekly monitoring of EBV-DNA and early intervention may be necessary.