Management of Peripheral T-Cell Lymphoma in Children and Adolescents Including STAT 3 Mutation Hyper-IgE Syndrome: One Size Does Not Fit All.

Peripheral T-cell lymphoma (PTCL) is a rare form of lymphoma in children with limited published data on treatment and lack of a uniformly accepted treatment algorithm. We retrospectively analyzed the data in children up to 18 years of age diagnosed to have PTCL from January 2016 to June 2020. The study included six children with a median age of 10 years, the youngest being a 7-month-old girl. According to the WHO-PTCL classification, three had PTCL-not otherwise specified (NOS), 2 had hepatosplenic TCL, and 1 had subcutaneous panniculitis-like TCL. All children had presented with advanced disease, 4 in St. Jude stage IV, 2 in St. Jude stage III. Three children received CHOEP chemotherapy including cyclophosphamide, doxorubicin, vincristine, prednisone, etoposide, while 1 child received CHOP. Two children received induction as per acute lymphoblastic leukemia followed by Bendamustine. Two patients succumbed to progressive disease, the infant with PTCL-NOS and 1 child with hepatosplenic TCL. Three children were in remission (median follow up of 44 mo). One child with PTCL-NOS Stage IV had an underlying STAT3 mutated hyperimmunoglobulin E syndrome and was in remission 12 months post a matched unrelated donor hematopoietic stem cell transplantation. He had grade 4 skin graft versus host disease and required extracorporeal photopheresis and ibrutinib, to which he had responded. CHOEP chemotherapy is well-tolerated and subcutaneous panniculitis-like TCL has the best prognosis thus far.

FLAG With Bortezomib in Childhood Relapsed/Refractory Leukemia: Remission Induction With Limited Toxicity in the Era of Multidrug-resistant Bacteria.

We present our experience on the use of fludarabine, cytarabine, granulocyte colony-stimulating factor in combination with Bortezomib. In total, 13 children with relapsed/refractory leukemia (acute lymphoblastic leukemia=9 and acute myeloid leukemia=4) were included from January 2018 to May 2019. Culture-positive sepsis and intensive care unit admission rates were 38% and 30%, respectively, with no postchemotherapy mortality in this cohort. Morphologic remission was documented in 92% and negative minimal residual disease was achieved in 61%, with 100% remission in those with acute myeloid leukemia. These results bear significant relevance in developing countries where multidrug-resistant sepsis is on the rise.

Augmented immunosuppression and PTCY-based haploidentical hematopoietic stem cell transplantation for thalassemia major.

Alternate donor HSCT for thalassemia major from a matched unrelated donor or haploidentical family donor is a feasible therapeutic option in children with no matched family donor. Aggressive pretransplant immunosuppression, reduced toxicity conditioning, and PTCY result in excellent thalassemia-free survival. We describe here our experience in this cohort. We performed a retrospective analysis of the data on children who underwent a haploidentical HSCT for thalassemia major with PTCY at our center from August 2017 to August 2019. All children received pretransplant immune suppression for 6 weeks with fludarabine and dexamethasone, hypertransfusion and chelation with intravenous desferrioxamine. Conditioning included thiotepa, fludarabine, rabbit ATG, and cyclophosphamide, and GvHD prophylaxis included PTCY with tacrolimus. Twenty children were included and nineteen children engrafted. Acute hypertension occurred in five children, bacterial infection in eight children and viral respiratory infection in three children. Three children suffered from graft rejection. Reactivation of viruses namely CMV, adenovirus, and BK virus was seen in 60% of children. Grades 1-2 acute GvHD of the skin in four children (20%) and limited chronic GvHD of the skin in four children (20%). Immune cytopenia was documented in three children (15%). Haploidentical HSCT offers a therapeutic option for children with thalassemia major with no suitably matched family or unrelated donors. Our reduced toxicity regimen with PTCY offers a DFS of 75% and OS of 95% with low transplant-related mortality of 5%.

Matched Family versus Alternative Donor Hematopoietic Stem Cell Transplantation for Patients with Thalassemia Major: Experience from a Tertiary Referral Center in South India.

Hematopoietic stem cell transplantation (HSCT) is the only curative option available for patients with thalassemia major in India with increasing access to alternate donor transplantation for patients with no matched family donor. We aimed to analyze the impact of family and alternate donor HSCT on morbidity and mortality post-HSCT. We conducted a retrospective study in the department between July 2007 and December 2018 where all children who underwent HSCT for thalassemia major were included. A total of 264 children were included with a median age of 6 years (male/female, 1.4:1). The graft source was matched related donor (MRD) (76%; parent 15%, sibling 85%) and matched unrelated donor (MUD) (22%). All children received a myeloablative conditioning regimen with treosulfan/thiotepa/fludarabine in 93% and busulfan/cyclophosphamide in 7%. The source of stem cells was peripheral blood in 61%, bone marrow in 38%, and umbilical cord blood in 3%. The incidence of bacteremia was 14% versus 25% in MRD versus MUD groups. There was a higher incidence of posterior reversible encephalopathy syndrome (PRES) in the MUD group (10% versus 3%). Engraftment occurred in 97% with a higher trend toward mixed chimerism in the MRD group (12% versus 2%). When indicated, whole-blood donor lymphocyte infusion was used to ensure complete chimerism in children in the MRD group. A statistically significant difference was found in the incidence of graft versus host disease (GVHD), both acute and chronic between the MUD versus MRD groups, 60% versus 20% and 41% versus 17%, respectively (P = .001). Similarly, immune cytopenia and cytomegalovirus reactivation were also significantly higher in the MUD group, 27% versus 1.4% and 25% versus 2%, respectively (P = .001). Thalassemia-free survival in our cohort was 96%, 94%, and 84% with a median follow-up of 65 months in the matched sibling donor, matched family donor, and MUD groups, respectively. Overall survival of 95% and 90% with a median follow-up of 65 months was noted in those who underwent transplantation less than and greater than 7 years of age, respectively. MUD transplantation for patients with thalassemia major involves specific challenges such as PRES and unusual manifestations of GVHD such as immune cytopenia. Early interventions to optimize supportive care and measures to reduce GVHD are required to ensure survival rates of over 90%.

Mendelian susceptibility to mycobacterial disease-Challenges in hematopoietic stem cell transplantation.

We present our experience in the hematopoietic stem cell transplantation (HSCT) in two children diagnosed with Mendelian susceptibility to mycobacterial diseases. The first child underwent a haploidentical HSCT with posttransplant cyclophosphamide using a reduced intensity conditioning following which he had primary graft failure. He was subsequently found to have interferon-γ1 receptor deficiency. He had immune reconstitution and is on antitubercular therapy. The second child diagnosed with IL12RB1 gene mutation underwent matched sibling donor HSCT with myeloablative conditioning following pretransplant immunosuppression with fludarabine and dexamethasone. He is 13 months post-HSCT with complete and remains disease free.

Treosulfan-based reduced toxicity hematopoietic stem cell transplantation in X-linked agammaglobulinemia: A cost-effective alternative to long-term immunoglobulin replacement in developing countries.

X-linked agammaglobulinemia (XLA) is a primary antibody disorder due to a mutation in the Bruton tyrosine kinase gene that requires lifelong immunoglobulin replacement resulting in a significant economic burden and treatment abandonment. Hematopoietic stem cell transplantation (HSCT) offers an alternative option for complete cure. In our series, two children with XLA underwent successful HSCT using a myeloablative conditioning with thiotepa, treosulfan, and fludarabine from a matched sibling donor. The second child had rejected his first graft following a busulfan-based regimen with resultant autologous reconstitution. At 6 months post-HSCT, serum IgG were normal, off IVIG, and had no infections. Both children after a median follow-up of 20 months have 100% chimerism. Treosulfan-based reduced toxicity myeloablative HSCT has encouraging results with a positive impact on the socioeconomics in developing countries.

Haploidentical Stem Cell Transplantation in Children with Benign Disorders: Improved Survival and Cost-Effective Care Over 15 Years from a Single Center in India.

We present our experience in haploidentical stem cell transplantation (haplo SCT) in children with benign disorders. We performed a retrospective study where children aged up to 18 years diagnosed to have benign disorders and underwent haplo SCT from 2002 to September 2017 were included. Of the 54 children, the most common indications were Fanconi anaemia 12 (22%), severe aplastic anaemia 8 (14%) and primary immune deficiency disorders (PID) 25 (46%). Post-transplant cyclophosphamide (PTCy) was used in 41 (75.9%) and ex vivo T depletion in 13 (24.1%). Engraftment rates were 70% with acute graft versus host disease in 36% and cytomegalovirus reactivation in 55% children. There was a statistically significant difference found between survival with siblings as donors as compared to parents (p value 0.018). Overall survival was 60% which is the 1-year survival, with 68% survival among those with PIDs. Cytokine release syndrome was noted in 12/41 (29%) of children who received T replete graft and PTCy. In children over 6 months of age, PTCy at a cost of INR 1200 provides cost effective T cell depletion comparable with TCR α/ß depletion priced at INR 1200,000. Haplo SCT is feasible option for cure in children with benign disorder.

Safety and efficacy of fresh whole blood donor lymphocyte infusion in children.

Donor lymphocyte infusion (DLI) is a form of cellular immunotherapy which is known to be effective in preventing relapse in leukemia by inducing graft versus leukemia (GVL) effect. In hematopoietic stem cell transplantation (HSCT) for benign hematological conditions including primary immune deficiency, mixed chimerism is seen with the use of reduced intensity conditioning. DLI can help prevent graft rejection by boosting the existing graft in these situations. There is scant data on the use of DLI in children who have undergone HSCT for benign hematological disorders. We present our case series with early withdrawal of immunosuppression and DLI as a means to mitigate relapse of leukemia and prevent graft rejection in mixed chimerism in children transplanted for benign hematological disorders. Donor lymphocyte infusion was given in a graded regimen with the cell dose of 1 × 105 CD3 cells/kg (1 × 104/kg in haploidentical transplant), 5 × 105 CD3 cells/kg, 1 × 106 CD3 cells/kg depending on the graft kinetics and the clinical status of the children. A total of fifty eight children including those with haploidentical donors underwent DLI with an overall survival of 81.1%. The use of fresh whole blood in very small aliquots from the donor has made this technique cost effective and an attractive form of immunotherapy.

Haploidentical Stem Cell Transplantation with Post-Transplant Cyclophosphamide for Primary Immune Deficiency Disorders in Children: Challenges and Outcome from a Tertiary Care Center in South India.

Haploidentical stem cell transplantation (haplo SCT) has emerged as an acceptable alternative to matched family donor transplantation for children diagnosed to have primary immune deficiency disorders (PIDs). We present data over 4 years on the challenges and efficacy of unmanipulated T cell replete haplo SCTs with post-transplant cyclophosphamide (PTCy) in children diagnosed to have PIDs. We performed a retrospective study in the pediatric blood and marrow transplantation unit where all children less than 18 years of age diagnosed to have PIDs and who underwent haplo SCT with PTCy from January 2014 to February 2018 were included in the study. Of the 16 transplants included in the study, 5 children were diagnosed to have Wiskott-Aldrich syndrome, 3 with congenital hemophagocytic lymphohistiocytosis, 2 each with Griscelli syndrome and Mendelian susceptibility to mycobacterial diseases, and one each with Chediak-Higashi syndrome, ORAI 1 mutation immune deficiency, severe combined immune deficiency, and Hyper IgM syndrome. The source of stem cells was PBSC in 62.5% and bone marrow in 32.5%. Engraftment by day 16-21 post hematopoietic stem cell transplantation was achieved in 75% transplants with 91% of these remaining in sustained complete chimerism. Acute skin and gut graft versus host disease of grade 2-3 were noted in 50% transplants and cytomegalovirus (CMV) reactivation in 43.7% transplants. One child with congenital HLH succumbed to refractory CMV, adenovirus, and BK virus infection. Cytokine release syndrome (CRS) was noted in 75% transplants with 2 children succumbing to the illness. Tocilizumab was successfully used early in one child. Overall mortality was found to be 37.5% with overall survival of 62.5% with a median follow-up of 23.3 months. In resource limited settings, PTCy has the potential to provide a cost-effective advantage in terms of accessibility of this curative procedure among children with PIDs.