HLA-DRB5 overexpression promotes platelet reduction in immune thrombocytopenia mice model by facilitating MHC-II-mediated antigen presentation.

INTRODUCTION: Major histocompatibility complex II (MHC-II)-mediated antigen presentation contributes to the pathogenesis of immune thrombocytopenia (ITP). Human leukocyte antigen (HLA)-DRB5 is an MHC-II molecule and this study aims to investigate its role and mechanisms in ITP development. METHODS: Guinea pig anti-mouse platelet (PLT) serum-induced ITP mice received tail vein injection of HLA-DRB5 overexpressing adenoviral vector/immune receptor expressed on myeloid cells-1 (IREM-1) monoclonal antibody (mAb). PLT count changes in mice blood were assessed by a haematology analyzer. MHC-II/CD80/CD86 expression in mice blood was measured by quantitative Real Time (qRT)-PCR and immunofluorescence assay. CD8+ T cell proportion in mice blood was detected by flow cytometry. RESULTS: HLA-DRB5 overexpression exacerbated PLT reduction since the 5th day of the establishment of ITP mice model and enhanced MHC-II/CD80/CD86 expression upregulation as well as CD8+ T cell ratio elevation in the blood of ITP mice while its effects were reversed by IREM-1 mAb. CONCLUSION: HLA-DRB5 overexpression upregulates MHC-II-mediated antigen presentation to CD8+ T cells, thus lowering PLT count in the ITP mice model.

HLA-DRB5 promotes immune thrombocytopenia via activating CD8+ T cells.

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by a low platelet (PLT) count and a high risk of bleeding, the clinical treatment for which still needs to be upgraded. Based on the critical role of human leukocyte antigen class II heterodimer ß5 (HLA-DRB5) in immune system, we herein investigated its effect on ITP. ITP murine models were established by the injection of guinea pig anti-mouse platelet serum (GP-APS), and the PLT of mouse peripheral blood was counted during the modeling. Quantitative real-time reverse transcription polymerase chain reaction, western blot and immunofluorescence assay was performed to quantify expressions of HLA-DRB5, major histocompatibility complex II (MHC-II) and co-stimulatory molecules (CD80, CD86). Flow cytometry was conducted to analyze the percentage of CD8+ T cells. As a result, the PLT count was decreased in mouse peripheral blood. Expressions of HLA-DRB5, MHC-II and co-stimulatory molecules, as well as the percentage of CD8+ T cells were elevated in peripheral blood of ITP mice. HLA-DRB5 knockdown mitigated ITP by increasing peripheral PLT level, downregulating expressions of MHC-II and co-stimulatory molecules and inactivating CD8+ T cells. Collectively, the downregulation of HLA-DRB5 restores the peripheral PLT count in ITP mice by reducing MHC-II-mediated antigen presentation of macrophages to inhibit the activation of CD8+ T cells.

Cryptococcosis with pulmonary cavitation in an immunocompetent child: a case report and literature review.

BACKGROUND: Pulmonary cryptococcosis (PC) rarely occurs in immunocompetent children. CASE PRESENTATION: A 13-year-old boy was admitted to the First Affiliated Hospital of Ningbo University in February 2023 with complaints of cough and chest pain. Physical examination showed slightly moist rales in the right lung. Chest computed tomography (CT) suggested a lung lesion and cavitation. Blood routine test, lymphocyte subsets, immunoglobulin, and complement tests indicated that the immune system was normal. However, the serum cryptococcal antigen test was positive. Next-generation sequencing revealed Cryptococcus infection. The child was diagnosed with PC and was discharged after treating with fluconazole 400 mg. Four months later, chest CT showed that the lung lesion diminished, and reexamination of serum cryptococcal antigen test turned positive. CONCLUSION: PC should be considered in an immunocompetent child with pulmonary cavities with nonspecific symptoms.

Tumor-suppressing effects of miR-381-3p in pediatric acute myeloid leukemia via ROCK1 downregulation.

MicroRNA (miR)-381-3p is the newly discovered tumor-associated miRNA, which is frequently associated with diverse human malignancies; but, it is still unknown about its effect on acute myeloid leukemia (AML) in children. This work focused on exploring miR-381-3p's effect on childhood AML and identifying the possible mechanisms facilitating new treatment development. Using qRT-PCR analysis, miR-381-3p expression remarkably reduced in pediatric AML patients and AML cell lines (HL-60 and U937). Following transfection of miR-381-3p mimic or inhibitor into HL-60 and U937 cells, we conducted MTT assay to evaluate cell proliferation, flow cytometry (FCM) to measured cell apoptosis and cell cycle, whereas Transwell assays to detect cell invasion and migration. Our results demonstrated that miR-381-3p overexpression remarkably repressed cell growth, invasion and migration; additionally, miR-381-3p overexpression resulted in arrest of cell cycle and enhanced cell apoptosis. In contrast, miR-381-3p knockdown led to an opposite effect. Moreover, we predicted miR-381's target gene and validated it by luciferase reporter assay and TargetScan, separately. We identified miR-381-3p's binding site in ROCK1 3'-UTR. As revealed by Western-blot (WB) assay, miR-381-3p overexpression notably suppressed ROCK1 level. Moreover, restoring ROCK1 expression abolished miR-381-3p's inhibition on cell proliferation, invasion and migration. Data in this work indicated the role of miR-381-3p as the tumor suppressor within pediatric AML by targeting ROCK1. Therefore, miR-381-3p might serve as a potential therapeutic target for the treatment of pediatric AML.

Homo sapiens circular RNA 0003602 (Hsa_circ_0003602) accelerates the tumorigenicity of acute myeloid leukemia by modulating miR-502-5p/IGF1R axis.

Acute myeloid leukemia (AML) has become a worldwide malignant cancer. We intended to investigate the critical roles and mechanism underlying homo sapiens circular RNA 0003602 (hsa_circ_0003602) in AML progression, especially in tumor cell proliferation, migration, invasion, and apoptosis. Real-time PCR was applied to identify the differential expression of hsa_circ_0003602 and miR-502-5p in AML bone marrow tissues and cell lines. In addition, western blot analysis was employed to determine the levels insulin-like growth factor 1 receptor (IGF1R) protein. The biological behaviors were assessed by CCK-8 cell viability assay, flow cytometry assay for apoptosis detection, and Transwell migration and invasion assay. The relationships between target miRNA and downstream mRNA were investigated by bioinformatics, luciferase reporter assay, and biotin-labeled RNA pull-down assay. Hsa_circ_0003602 was upregulated and predicted poor survival in AML. Knockdown of hsa_circ_0003602 in AML cell lines induced the inhibition of proliferation, migration, and invasion and caused apoptosis. Hsa_circ_0003602 sequestered miR-502-5p by functioning as a competitive endogenous RNA (ceRNA), thereby regulating IGF1R expression. Hsa_circ_0003602 acted as a tumor promoter in AML via miR-502-5p/IGF1R axis. Our study provides evidence that hsa_circ_0003602, miR-502-5p, and IGF1R might form a regulatory axis to affect the carcinogenicity of AML cells and provide potential targets for the treatment of AML.

Early outcomes of primary repair versus reconstruction for acute anterior cruciate ligament injury: A systematic review and meta-analysis.

BACKGROUND: Contemporary techniques for repair of acute anterior cruciate ligament (ACL) rupture have been receiving renewed interest recently because of reports of good outcomes. METHODS: A literature search of PUBMED, MEDLINE, EMBASE, and the Cochrane Library was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Only RCTs published in English and comparing clinical outcomes of ACL repair versus reconstruction were included. Outcomes were evaluated using the International Knee Documentation Committee subjective score, Lysholm score, Tegner activity scale, visual analog scale pain score, anterior laxity, Lachman test, hop tests, knee injury and osteoarthritis outcome score, extension deficit, revision rate, and re-rupture rate. Statistical analysis was performed with Review Manager 5.4 and Stata 14.0. Two-tailed P < .05 was considered statistically significant. RESULTS: Four RCTs (with a total of 293 patients) that met the eligibility criteria were included in this review. Over short-term follow-up, none of the studies found significant differences between the repair groups and reconstruction groups with respect to International Knee Documentation Committee, Lysholm, Tegner, visual analog scale, anterior laxity, Lachman test, re-rupture rate, extension deficit, and performance of 3 hop tests (P > .05). In both groups, the hop tests scores were >90%. CONCLUSION: ACL repair and ACL reconstruction appear to provide comparable short-term outcomes. The low revision rate after primary repair is encouraging. For patients with ACL injury, current repair techniques such as dynamic intraligamentary stabilization and bridge-enhanced ACL repair may be an effective alternative to reconstruction.

Association of image-defined risk factors, tumor resectability, and prognosis in children with localized neuroblastoma.

BACKGROUND: Although localized neuroblastoma has a good prognosis, some cases have undergone treatment failure or recurrence. Apart from biologic features such as MYCN status, we wondered whether some characteristics of growing tumors are prognostic, such as a well-encapsulated mass without infiltration of vital organs. We analyzed the diagnostic utility of image-defined risk factors (IDRFs) to predict successful treatment and prognosis. The overall goal was to achieve maximum cure rates for patients with localized neuroblastoma through a better understanding of clinical characteristics. METHODS: We retrospectively reviewed the images of patients with localized neuroblastoma who were enrolled between June 1998 and December 2012 at a single institution in Shanghai, China. Unequivocal categorization regarding IDRFs was available in 67 patients. IDRF was assessed at diagnosis and after four cycles of neoadjuvant chemotherapy, on average. The median follow-up period was 84 months (range: 48-132 months) after diagnosis. RESULTS: MRI and CT indicated a total of 177 IDRFs in these 67 patients. Logistic regression analysis revealed a highly significant negative correlation between the numbers of IDRFs and the possibility of complete removal of neuroblastoma. Intraspinal extension of the tumor, compression of the trachea, and encasement of the main artery in localized neuroblastoma were predictors for incomplete tumor resection. According to univariate analysis, ≥ 4 IDRFs and intraspinal extension of the tumor were significant indicators of poor prognosis. CONCLUSIONS: The number of IDRFs was useful in predicting surgical outcome and event-free survival. The number of IDRFs should be considered in protocol planning, instead of IDRF presence or absence.

Investigating the potential benefit of second biopsy of residual mass in pediatric mature B cell non-Hodgkin lymphoma.

OBJECTIVES: To assess the impact of second-look biopsy of residual mass during or after chemotherapy in pediatric mature B-cell NHL. METHODS: Patients with mature B-cell non-Hodgkin lymphoma (NHL) who were suspicious of radiological residual mass at mid or end of treatment and subjected to second biopsy were treated at our center between January 2001 and December 2015. Their clinical characteristics, imaging findings, pathological changes, management, and prognosis were reviewed retrospectively. RESULTS: A total of 31 children were included (13 boys and 18 girls, median age at diagnosis 6.1 years). The median time from diagnosis to second biopsy was 3.15 months (range 2.3-18 months). Biopsy confirmed the presence of viable tumor in eight patients. The specificity and positive predictive value of conventional imaging in detecting residual detectable by biopsy were at 9 and 28.6%, while sensitivity and negative predictive value of this approach were both 100%. Three of the histologic positive patients experienced progressive disease or relapse while the others achieved complete remission (CR) and 21 patients achieved long-time CR at median follow-up of 3.2 years. The median progression-free survival (PFS) time of all 31 was 28 months and 5-year PFS rate was 90.0%. Five-year PFS rate of negative-biopsy and positive-biopsy group were 100 and 62.5%, respectively (p = 0.002). CONCLUSION: Conventional imaging has very high sensitivity but very low specificity for the accurate determination of residual disease in pediatric NHL. Second-look biopsy is necessary to differentiate viable tumor from necrosis or fibrosis and is solid evidence-based foundation of subsequent treatment.

Downregulation of PDIA3 inhibits proliferation and invasion of human acute myeloid leukemia cells.

INTRODUCTION: Acute myeloid leukemia (AML) is a common malignancy of the hematopoietic system. In bone marrow samples of AML patients, PDIA3 expression was higher than that in the samples of healthy controls. We aimed at exploring the effect of PDIA3 siRNA on proliferation, apoptosis, migration, and invasion of AML HL-60 and HEL cells. MATERIALS AND METHODS: RT-PCR was performed to identify PDIA3 expression. Cell proliferation was assessed by MTT. Flow cytometry analysis and transwell were used to detect cell apoptosis, migration and invasion. Gene set enrich-ment analysis (GSEA) was employed to explore the PDIA 3-associated pathways in AML. Western blotting was used for protein expression detection. RESULTS: PDIA3 siRNA significantly inhibited the proliferation of AML cells at 24 and 48 h. PDIA3 siRNA notably enhanced the percentage of apoptotic cells. The migration and invasion abilities of HL-60 and HEL cells in the PDIA3 siRNA group were significantly suppressed compared with those in the control and siNC groups. GSEA of the Cancer Genome Atlas dataset showed that Kyoto Encyclopedia of Genes and Genomes oxidative phosphorylation and amino sugar and nucleotide sugar metabolism pathways could be correlated with PDIA3 expression; this was further confirmed in AML cells by Western blotting. MAPK signaling was also blocked by PDIA3 siRNA. CONCLUSION: PDIA3 siRNA effectively enhanced apoptosis, and suppressed proliferation, invasion, and migration of AML cells by regulating oxidative phosphorylation and amino sugar and nucleotide sugar metabolism pathways, and MAPK signaling, which can provide novel therapeutic targets for AML.

[Advances in targeted therapy for childhood acute myeloid leukemia].

At present, acute myeloid leukemia (AML) accounts for about 15%-20% of childhood acute leukemia. Although overall survival rate is increasing with the help of risk stratification, stratification of chemotherapy, and supportive treatment, conventional pharmacotherapy still has a limited clinical effect and certain limitations in improving remission rate in previously untreated patients and reducing recurrence after remission. With the development of precision medicine, the mechanisms of targeted therapy, including abnormal activation of AML-related signaling pathways and epigenetic modification, have been found in recent years. Molecular-targeted drugs can therefore act on specific receptors and target genes to improve clinical effect and the prognosis of AML patients.

Identification and Validation of Gene Expression Pattern and Signature in Patients with Immune Thrombocytopenia.

In the present study, we sought to define genes associated with immune thrombocytopenia (ITP). Microarray analysis revealed that of 1002 genes associated with ITP, 309 genes had downregulated expression and 693 genes had upregulated expression in patients with ITP. Gene set enrichment analysis revealed that 11 pathways were positively correlated to ITP, such as type I diabetes mellitus, intestinal immune network for IgA production, and oxidative phosphorylation. The messenger RNA expression levels of the indicated genes, including HLA-DRB5, IGHV3-66, IFI27, FAM212A, PLD5, tumor necrosis factor (TNF)-α, interferon-γ, interleukin (IL)-1ß, and IL-4, were significantly increased in patients with ITP compared with healthy humans, while MMP8, SLC1A3, CRISP3, THBS1, FMN1, and IL-10 were decreased. In conclusion, the gene expression profile of patients with ITP has established a foundation to study the gene mechanism of ITP progression.

Portulacerebroside A inhibits adhesion, migration, and invasion of human leukemia HL60 cells and U937 cells through the regulation of p38/JNK signaling pathway.

Acute myeloid leukemia (AML) is a highly malignant hematopoietic tumor. This study aimed to explore the effect of portulacerebroside A (PCA) on the adhesion, migration, and invasion in human leukemia HL60 cells and U937 cells and clarify the possible mechanisms involved, which could provide potential strategies for the treatment of AML. By methyl thiazolyl tetrazolium analysis, it was found that PCA (1-10 µM) suppressed the cell viability in a time- and dose-dependent manner. A total of 1, 2, and 5 µM of PCA dramatically inhibited the adhesion, migration, and invasion of HL60 cells and U937 cells in a dose-dependent manner. Phosphorylation level of JNK and P38 protein level was measured by Western blot. After the real-time quantification polymerase chain reaction and Western blot detection of the total RNA and protein, messenger RNA, and protein expression levels of Ras homologous C (RhoC), metastasis-associated gene 1 (MTA1) and matrix metalloproteinase-2/9 (MMP-2/9) were decreased significantly in a dose-dependent manner. The phosphorylation level of c-Jun N-terminal kinase (JNK) and P38 mitogen-activated protein kinase (P38) was decreased dramatically in HL60 cells and U937 cells after PCA treatment. In conclusion, PCA significantly inhibits the adhesion, migration, and invasion of HL60 cells and U937 cells by suppressing the p38/JNK pathway and regulating the expressions of related genes.

Renal tumor in developing countries: 142 cases from a single institution at Shanghai, China.

BACKGROUND: The clinical management of children with renal tumors including Wilms' tumor, clear cell sarcoma, rhabdoid tumor and other renal tumors in our center was designed according to the National Wilms' Tumor Study Group protocols. METHODS: A total of 142 consecutive patients who had been diagnosed as having renal tumors at Shanghai Children's Medical Center were reviewed retrospectively in the period of December 1998 and September 2012. Diagnosis and treatment were decided by a multidisciplinary team including oncologists, surgeons, pathologists and sub-specialized radiologists. RESULTS: The median age of the patients at the time of diagnosis was 27 months. The tumor stages of the patients were as follows: stage I 24.6%, stage II 23.2%, stage III 32.3%, stage IV 14.1%, and stage V 5.6%. Favorable histology was diagnosed in 80.3%, anaplasia in 4.2%, clear cell sarcoma in 9.8%, rhabdoid tumor in 4.9%, and other renal tumors in 0.7% of the patients. The event-free and overall 5-year survival rates were 80% and 83%, respectively. Tumor relapse and progress was seen in 25 patients (17.6%). The median relapse time was 6 months (range: 2-37 months). Seven relapsing patients were retreated and four of them got second complete remission (three in stage II, one in stage I). CONCLUSION: A multi-disciplinary team work model is feasible in developing countries, and the renal tumors protocols basically from developed countries are safe in developing countries.

Effects of portulacerebroside a on apoptosis of human leukemia HL60 cells and p38/JNK signaling pathway.

Acute myeloid leukemia is known as one of the most malignant diseases. We aimed at exploring the effect of portulacerebroside A (PCA) on the apoptosis in human leukemia HL60 cells and clarify the possible mechanisms involved in. By MTT analysis, we found that PCA (1-100 µM) inhibited the cell viability in a time- and dose-dependent manner, and cell cycle was arrested at G0/G1 period. PCA treatment from 5 to 50 µM dose-dependently induced apoptosis from 12.7 ± 1.56% to 52.7 ± 6.214% of HL60 cells. Mitochondrial membrane potential (MMP) was decreased and reactive oxygen species (ROS) accumulated obviously. mRNA expressions and protein levels of Bax/Bcl-2, caspase-3 and caspase-9 were elevated significantly. ERK1/2, JNK1/2 and p38 MAPK pathway were blocked detected by western blot analysis. In conclusion, PCA can act as a new agent for leucocythemia treatment.

[Classification therapy in 405 children with immune thrombocytopenia].

OBJECTIVE: To explore the efficiency and safety of immune thrombocytopenia（ITP）in children through classification treatment. METHODS: 405 newly diagnosed ITP patients were enrolled in this study from January 1st 2013 to August 31st 2014. The cases were divided into observation group and therapy group according to the initial platelet count of less than 20×109/L or the cases of active bleeding. There were 104 male cases and 76 female cases in observation group with the media platelet count of 46 （20-89）×109/L. They were followed up with a median of 20 months. The therapy group，including 131 males and 94 females with a median platelet count of 11（1-19）×109/L, were followed up by 22 months. RESULTS: The total curative rate at acute period was 80.44%（181/225）in therapy group with the first line treatment. In observation group, 148 cases（82.22%）reached complete response（CR）or response（R） criteria. 44 patients came into persistent period with an effective rate of 34.09%（15/44）in therapy group. The overall effectiveness over one year was 87.11%（196/255）. In observation group, 32 cases came into persistent period and 13 cases（40.63%）got the CR or R line. After one year of observation, 161 cases （89.44%）reached the CR or R standard. In therapy group, 5 out of 29 patients（17.24%）in chronic period got CR or R. While in observation group, 6 out of 19 cases（31.58%）reached the CR or R standard. The elder children over 10 years had risk factors in response in two groups. There was no severe bleeding or adverse effect or dead cases in this study. CONCLUSION: It is reasonable to take platelet count <20×109/L and（or）active bleeding as the dividing line for classification therapy indications. Nearly half of the cases could avoid over therapy and decreased the risk of drugs side effect to improve life quality.

[Long-term follow-ups of comprehensive therapies for stage 4 neuroblastoma].

OBJECTIVE: To evaluate the long-term outcomes of childhood stage 4 neuroblastoma (NB) and its correlative prognostic factors. METHODS: Comprehensive protocols including tumor resection, intensive chemotherapy, radiotherapy, autologous bone marrow transplantation and 13-cis-retinoid were designed and implemented. A total of 112 newly diagnosed NB stage 4 patients at Shanghai Children's Medical Center collected from June 1998 to December 2010 were treated. Their clinical features, therapeutic efficacies, long-term outcomes and prognostic factors were analyzed. RESULTS: There were 69 males and 43 females with an age range of 4 months to 15 years. Among them, 12 improving patients didn't complete treatment because of parental decisions. Among those completing the comprehensive protocols, 62 cases (62.0%) achieved very good partial remission (VGPR), 20 (20.0%) achieved partial remission (PR) while another 18 (18.0%) progressed during treatment. The efficiency rate (including VGPR+PR) of treatment was 82.0 % (n = 82). The median follow-up period was 78 (56, 120) months. And 13 cases were lost after a median follow-up of 16 months. The 2, 3, 5-year event-free survival (EFS) was 56.2% (59/105) , 40.8% (40/98) and 21.1% (19/90) respectively. Age (>18 months), poor curative effect (achieving no VGPR at the end of treatment), elevated level of lactate dehydrogenase (LDH) (> 5 times normal value), bone marrow involvement and brain metastasis were poor prognostic factors (χ(2) = 12.01, 13.66, 6.29, 5.44, 16.18, all P < 0.05) . According to the multivariate estimates of hazards, age, high levels of LDH, poor curative effect and brain metastasis were associated with a worse survival (OR = 3.54, 1.89, 3.08, 3.45, all P < 0.05) . Brain metastasis predicted a worse outcome with 100% mortality rate (n = 6). Compared to traditional chemotherapy, topotecan-based chemotherapy could not improved the efficiency (52.6% (10/19) vs 63.2% (36/57) , P > 0.05) and long-term outcome (2 ys-EFS 42.1% (8/19) vs 56.4% (31/55) , P > 0.05). CONCLUSIONS: The prognosis remains poor for neuroblastoma of stage 4. Age (>18 months), poor curative effect (achieving no VGPR at the end of treatment), elevated LDH level (>5 times normal value) and bone marrow infiltration are associated with worse prognosis. Brain metastasis predicts the worst with 100% death rate. Topotecan included chemotherapy can not be proved more effective in this study.

ATG-Fresenius S combined with cyclosporine a: an effective immunosuppressive therapy for children with aplastic anemia.

For the first time, we conducted a 2-center retrospective study to show the efficacy of antithymocyte globulin (ATG)-Fresenius S plus cyclosporine treatment of children with severe aplastic anemia. From March 1997 to May 2011, a total of 124 patients (median age, 7.5 y; range, 1.5 to 16 y) from 2 centers with acquired AA treated with an immunosuppressive therapy (IST) regimen, consisting of ATG-Fresenius S (5 mg/kg per day for 5 d) and cyclosporine, were enrolled. The response rate was 55.6%. The median time between IST and response was 6 (0.5 to 18) months. After a median follow-up time of 29 (6 to 153) months, the rates of relapse and clonal evolution were 3.2% and 0.8%, respectively. Overall, 17 patients (13.7%) died in this study: 14 resulted from sepsis, 1 resulted from intracranial hemorrhage, 1 occurred after hematopoietic stem cell transplantation, and 1 resulted from clonal disease progression. The 5-year overall survival rate for the entire cohort was 74.7%. IST responders had a better survival rate (100%) than nonresponders (70.7%). The use of ATG-Fresenius S plus cyclosporine as a first-line immunosuppressive treatment appeared to be effective for children with severe aplastic anemia in our study. ATG-Fresenius S could be another option in the treatment arsenal, especially in countries where the other ATG products are harder to acquire.

Clinical outcome of childhood lymphoblastic lymphoma in Shanghai China 2001-2010.

BACKGROUND: This retrospective cohort study analysed the clinical characteristics and outcomes of patients with childhood lymphoblastic lymphoma (LBL) treated in Shanghai, China. PROCEDURE: From 2001 to 2010, 108 evaluable patients ≤16 years of age who were newly diagnosed with biopsy-proven LBL were treated with one of three treatment protocols: CCCG-99, SCMC-T-NHL-2002, or LBL-CHOF-2006. RESULTS: Two patients had Stage I disease, 5 had Stage II, 55 had Stage III, and 46 had Stage IV. The immunophenotype was T-cell LBL in 92 patients (85.2%) and precursor B-cell LBL in 16 (14.8%). The abandonment rate was 11.5%. Twenty-five patients (23.2%) suffered from resistant disease, including 1 with isolated central nervous system (CNS) relapse. At a median follow-up of 40.4 months (range, 0-114 months), the 5-year probability of event-free survival (pEFS) was 63.9 ± 4.6% in all patients. The 5-year pEFS for patients with pB-LBL was better than for patients with T-LBL (100% vs. 61.3 ± 5.1%, P = 0.007). Patients who had achieved complete remission on day 33 of induction had significantly better pEFS than those who had not (78.8 ± 4.6% vs. 28.2 ± 9.0%, P = 0.000). Three of 25 patients who experienced resistant disease were alive at the end of the study period. CONCLUSIONS: The abandonment rate was lower for patients with LBL than for patients with acute lymphoblastic leukemia. Prophylactic cranial radiation can be omitted for patients with LBL even when advanced-stage disease is present, as intensive systemic chemotherapy with intrathecal therapy is sufficient to prevent CNS relapse. The survival of patients with resistant disease was very poor.