Rare Non-Hodgkin Lymphoma in Childhood; A Single Center Experience / 임상소아혈액종양

BACKGROUND: Among pediatric non-Hodgkin lymphomas, there are 4 major subtypes: Burkitt lymphoma, lymphoblastic lymphoma, diffuse large B-cell lymphoma, and anaplastic large-cell lymphoma. Understanding of other rare subtypes derives only from small pediatric case series. We report our institutional experience with rare pediatric NHLs.METHODS: Thirty-six cases of rare NHL subtypes diagnosed at the Asan Medical Center from 1995 to 2015 were evaluated. We retrospectively reviewed the clinical and pathologic features and outcomes of these patients, excluding peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS), and extranodal NK/T-cell lymphoma (ENKL), on which we have previously reported.RESULTS: There were 23 cases of T-cell lineage (13 PTCL, 6 ENKL, 2 subcutaneous panniculitis-like T-cell lymphoma, 1 primary cutaneous CD4+2016-11-22 small/medium sized T-cell lymphoma, 1 enteropathy-associated T-cell lymphoma) and 13 cases of B-cell lineage lymphoma (5 marginal zone lymphoma, 6 primary mediastinal large B-cell lymphoma, 2 immunoblastic and plasmablastic lymphoma). All patients were treated with chemotherapy with or without surgery, except 4 out of 5 patients with marginal zone lymphoma who received surgery only. Two patients died and 6 patients relapsed. One patient with primary mediastinal large B-cell lymphoma received autologous peripheral blood stem cell transplantation. The 5-year overall survival and event-free survival rates of rare pediatric NHL excluding PTCL, NOS, and ENKL was 80.0% and 72.0%, respectively.CONCLUSION: Children diagnosed with rare pediatric NHL other than PTCL, NOS, and ENKL showed variable incidence and treatment outcomes. Multicenter studies in larger cohorts are needed for better understanding of these rare NHL subtypes in childhood.

Rare Non-Hodgkin Lymphoma in Childhood; A Single Center Experience / 임상소아혈액종양

BACKGROUND: Among pediatric non-Hodgkin lymphomas, there are 4 major subtypes: Burkitt lymphoma, lymphoblastic lymphoma, diffuse large B-cell lymphoma, and anaplastic large-cell lymphoma. Understanding of other rare subtypes derives only from small pediatric case series. We report our institutional experience with rare pediatric NHLs. METHODS: Thirty-six cases of rare NHL subtypes diagnosed at the Asan Medical Center from 1995 to 2015 were evaluated. We retrospectively reviewed the clinical and pathologic features and outcomes of these patients, excluding peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS), and extranodal NK/T-cell lymphoma (ENKL), on which we have previously reported. RESULTS: There were 23 cases of T-cell lineage (13 PTCL, 6 ENKL, 2 subcutaneous panniculitis-like T-cell lymphoma, 1 primary cutaneous CD4+2016-11-22 small/medium sized T-cell lymphoma, 1 enteropathy-associated T-cell lymphoma) and 13 cases of B-cell lineage lymphoma (5 marginal zone lymphoma, 6 primary mediastinal large B-cell lymphoma, 2 immunoblastic and plasmablastic lymphoma). All patients were treated with chemotherapy with or without surgery, except 4 out of 5 patients with marginal zone lymphoma who received surgery only. Two patients died and 6 patients relapsed. One patient with primary mediastinal large B-cell lymphoma received autologous peripheral blood stem cell transplantation. The 5-year overall survival and event-free survival rates of rare pediatric NHL excluding PTCL, NOS, and ENKL was 80.0% and 72.0%, respectively. CONCLUSION: Children diagnosed with rare pediatric NHL other than PTCL, NOS, and ENKL showed variable incidence and treatment outcomes. Multicenter studies in larger cohorts are needed for better understanding of these rare NHL subtypes in childhood.

Favorable outcome of allogeneic hematopoietic stem cell transplantation followed by post-transplant treatment with imatinib in children with Philadelphia chromosome-positive acute lymphoblastic leukemia

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) is the preferred curative therapy for children with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL). We evaluated the treatment outcomes of children with Ph+ ALL who underwent allogeneic HSCT. METHODS: Fifteen children diagnosed with Ph+ ALL in Asan Medical Center Children's Hospital between 1998 and 2012 were retrospectively analyzed. RESULTS: Of 521 children diagnosed with ALL during the study period, 15 had a Philadelphia chromosome. Among these 15 patients, 13 attained complete remission (CR) following induction chemotherapy, and two died of intracerebral hemorrhage during leukapheresis and induction chemotherapy, respectively. Of the 13 patients who attained CR, 12 received allogeneic HSCT, mainly from unrelated donors. Of the 12 patients who received HSCT, one died of a transplant-related cause, one died of relapse after HSCT, and 10 remain in continuous CR. Of the 10 patients who remained in CR longer than six months after HSCT, seven received post-HSCT imatinib. For all 15 patients, the 5-year overall survival, event-free survival, and cumulative incidence of relapse were 60.0%, 48.6%, and 38.8%, respectively, with a median follow-up of 70 months. For the HSCT group, the 5-year overall survival, event-free survival, and cumulative incidence of relapse were 80.2%, 72.9%, and 29.3%, respectively, with a median follow-up of 100 months. CONCLUSION: Allogeneic HSCT cures a significant proportion of Ph+ ALL patients. Because the use of imatinib appears to be a promising approach, strategies that include tyrosine kinase inhibitors before and after HSCT require further evaluation.

Clinical Characteristics and Treatment Outcomes of Non-anaplastic Peripheral T-Cell Lymphoma in Children and Adolescents: A Single-center Experience / 임상소아혈액종양

BACKGROUND: Peripheral T-cell lymphoma (PTCL) is a rare form of non-Hodgkin's lymphoma (NHL), and it is usually associated with poor outcome. Here, we report our experience in treating this disease over 19 years, with the aim of helping to establish better treatment methods.METHODS: We retrospectively investigated 18 non-anaplastic PTCL cases that were diagnosed at a medical center in Seoul between October 1995 and October 2014. The clinical characteristics, treatments, and outcomes were reviewed.RESULTS: According to the World Health Organization (WHO) classifications for PTCL, 11 patients had PTCL, not otherwise specified (PTCL-NOS), 6 patients had extranodal natural killer/T-cell lymphoma, nasal type (ENKL), and 1 patient had subcutaneous panniculitis-like T-cell lymphoma. Patients were treated with various chemotherapeutic regimens. Of these 18 patients, 5 (27.7%) relapsed and 7 (38.9%) died from disease progression. Two relapsed patients received high-dose chemotherapy with autologous hematopoietic stem cell transplantation (HDCT-ASCT). The 5-year event-free and overall survival rates were 43.2% and 66.7% in all cases, 45.5% and 54.5% in PTCL-NOS, and, 25.0% and 83.3% in ENKL, respectively.CONCLUSION: PTCL-NOS showed a suboptimal outcome. Among 6 ENKL patients, 3 relapsed, but 2 of 3 relapsed patients were salvaged. For better prognosis, HDCT-ASCT in relapsing and refractory PTCL and chemo-radiotherapy in ENKL could be considered as a salvage treatment. Larger studies are needed to confirm the outcome. Furthermore, an effort should be made to develop more efficient initial therapies through collaborative research.

Clinical Characteristics and Treatment Outcomes of Non-anaplastic Peripheral T-Cell Lymphoma in Children and Adolescents: A Single-center Experience / 임상소아혈액종양

BACKGROUND: Peripheral T-cell lymphoma (PTCL) is a rare form of non-Hodgkin's lymphoma (NHL), and it is usually associated with poor outcome. Here, we report our experience in treating this disease over 19 years, with the aim of helping to establish better treatment methods. METHODS: We retrospectively investigated 18 non-anaplastic PTCL cases that were diagnosed at a medical center in Seoul between October 1995 and October 2014. The clinical characteristics, treatments, and outcomes were reviewed. RESULTS: According to the World Health Organization (WHO) classifications for PTCL, 11 patients had PTCL, not otherwise specified (PTCL-NOS), 6 patients had extranodal natural killer/T-cell lymphoma, nasal type (ENKL), and 1 patient had subcutaneous panniculitis-like T-cell lymphoma. Patients were treated with various chemotherapeutic regimens. Of these 18 patients, 5 (27.7%) relapsed and 7 (38.9%) died from disease progression. Two relapsed patients received high-dose chemotherapy with autologous hematopoietic stem cell transplantation (HDCT-ASCT). The 5-year event-free and overall survival rates were 43.2% and 66.7% in all cases, 45.5% and 54.5% in PTCL-NOS, and, 25.0% and 83.3% in ENKL, respectively. CONCLUSION: PTCL-NOS showed a suboptimal outcome. Among 6 ENKL patients, 3 relapsed, but 2 of 3 relapsed patients were salvaged. For better prognosis, HDCT-ASCT in relapsing and refractory PTCL and chemo-radiotherapy in ENKL could be considered as a salvage treatment. Larger studies are needed to confirm the outcome. Furthermore, an effort should be made to develop more efficient initial therapies through collaborative research.

A case of Mowat-Wilson syndrome with developmental delays and Hirschsprung's disease

Mowat-Wilson syndrome is an extremely rare genetic disease that is characterized by intellectual disability, facial dysmorphism, Hirschsprung's disease, and other congenital anomalies. This disorder is caused by heterozygous mutations or deletions in the zinc finger E-box-binding homeobox-2 gene (ZEB2). Thus far, approximately 200 cases of Mowat-Wilson syndrome have been reported worldwide. In Korea, only one case with a 2q22 deletion, which also affects ZEB2, has been previously reported. Here, we describe a patient with Mowat-Wilson syndrome who presented with developmental delays, typical facial dysmorphism, and Hirschsprung's disease. Molecular analysis of ZEB2 identified a novel heterozygous mutation at c.190dup (p.S64Kfs*6). To our knowledge, this is the second report of a Korean patient with Mowat-Wilson syndrome that has been confirmed genetically.