Kenji Kishi

Myeloablative allogeneic hematopoietic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia in adults: significant roles of total body irradiation and chronic graft-versus-host disease.

Summary:Disease-free survival in Philadelphia chromosome-positive ALL (Ph+ALL) is very poor, and allogeneic hematopoietic stem cell transplantation (allo-HSCT) is currently considered the only procedure with curative potential. To identify factors affecting transplant outcome, we analyzed the data from 197 Ph+ALL patients aged 16 years or older who had undergone allo-HSCT. The 5-year survival rates were 34% for patients in first complete remission (CR), 21% for those in second or subsequent CR, and 9% for those with active disease (P<0.0001). Multivariate analysis showed four pre-transplant factors as significantly associated with better survival: younger age, CR at the time of transplantation, conditioning with total body irradiation, and HLA-identical sibling donor (P<0.0001, P<0.0001, P=0.0301, P=0.0412, respectively). Severe acute GVHD increased the risk of treatment-related mortality (TRM) without diminishing the risk of relapse, whereas chronic GVHD reduced the risk of relapse without increasing the risk of TRM. Thus, patients who developed extensive chronic GVHD had better survivals (P=0.0217), and those who developed grade III–IV acute GVHD had worse survivals (P=0.0023) than did the others.

Human herpesvirus 6 meningoencephalitis in allogeneic hematopoietic stem cell transplant recipients

We retrospectively investigated the clinical characteristics of human herpesvirus 6 (HHV-6) meningoencephalitis within 100 days after allogeneic hematopoietic stem cell transplantation (HSCT). Of 1148 patients who received transplants between January 1999 and December 2003, 11 patients (0.96%) with HHV-6 meningoencephalitis were identified. Ten of 11 recipients received hematopoietic stem cells from donors other than HLA-identical siblings. Confusion was the most frequent central nervous system (CNS) symptom, and a skin rash with high-grade fever preceded the CNS symptoms in 9 patients. Magnetic resonance imaging of the brain showed an abnormal increased T2 signal in the hypothalamus of 5 patients. Eight patients were treated with ganciclovir, and an improvement of CNS symptoms was obtained in 3 patients; 3 patients treated with acyclovir showed no improvement. Improvement in the meningoencephalitis seemed less frequent in patients with abnormal findings in the hypothalamus than in those without such findings. Because the symptoms of HHV-6 meningoencephalitis mimicked those of cyclosporine- or tacrolimus-induced encephalopathy, the drugs were withdrawn at the onset of CNS symptoms in 10 patients, resulting in the development of grade IV graft-versus-host disease (GVHD) in 5 patients.Three patients died of HHV-6 menin-goencephalitis, and 6 died of other causes, including GVHD. In conclusion, HHV-6 meningoencephalitis is a rare but potentially life-threatening complication in patients who undergo allogeneic HSCT. Careful assessment of the clinical findings and the brain may allow early and precise diagnosis of HHV-6 meningoencephalitis and contribute to improving its prognosis.

Comparative analysis of clinical outcomes after allogeneic bone marrow transplantation versus peripheral blood stem cell transplantation from a related donor in Japanese patients

A reduced incidence of graft versus host disease (GvHD) has been documented among Japanese allogeneic bone marrow transplantation (BMT) patients, as the Japanese are genetically more homogeneous than western populations. To clarify whether this ethnic difference affects the results of allogeneic peripheral blood stem cell transplantation (PBSCT), we conducted a nationwide survey to compare clinical outcomes of allogeneic PBSCT (n = 214) and BMT (n = 295) from a human leucocyte antigen‐identical‐related donor in Japanese patients. The cumulative incidence of grades II–IV acute GvHD was 37·4% for PBSCT and 32·0% for BMT. The cumulative incidence of extensive chronic GvHD at 1 year was significantly higher after PBSCT than BMT (42% vs. 27%; P < 0·01). The organ involvement patterns of GvHD were different between the two groups. By multivariate analyses, the incidence of chronic GvHD was significantly increased in PBSCT, whereas the stem cell source did not affect the incidence of acute GvHD, transplant‐related mortality, relapse or survival. We concluded that Japanese PBSCT patients have an increased risk of chronic GvHD compared with BMT patients, but the incidence of acute GvHD was still lower than in western populations. Thus, the choice of haematopoietic stem cell source should be considered based on data for individual ethnic populations.

Secondary solid tumors after allogeneic hematopoietic SCT in Japan.

To evaluate the incidence and risk factors for secondary solid tumors in Japan after allogeneic hematopoietic SCT (allo-HSCT), 2062 patients who had received allo-HSCT between 1984 and 2005 were retrospectively analyzed. Twenty-eight patients who developed 30 solid tumors were identified a median of 5.6 years after transplantation. The risk for developing tumors was 2.16-fold higher than that of the age- and sex-adjusted general population. The cumulative incidence of solid tumors at 10 years after allo-HSCT was 2.4%. The risk was significantly higher for tumors of the skin, oral cavity and esophagus (standard incidental ratio 40.23, 35.25 and 10.73, respectively). No increase in gastric, colon or lung cancer, despite being the most prevalent neoplasm in the Japanese, was observed. In multivariate analysis, occurrence of chronic GVHD and malignant lymphoma as a primary disease was associated with a higher risk for developing solid tumors. Eighteen patients are still alive, and their 5-year probability of survival since diagnosis of solid tumors is 59.7%. Our data suggest that the incidence and risk factors of secondary solid tumors in Japanese allo-HSCT recipients are comparable to those reported in Western countries and emphasize that the early detection of solid tumors has a crucial role in improving OS.