Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fifty consecutive adult patients with acute lymphoblastic leukemia (ALL) were treated with an intensive cyclical chemotherapy and the mean received dose of individual cytotoxic drug was retrospectively studied. The median age was 28 years. Twenty-one (43%) had white blood cell (WBC) count over 30 x 10(9)/l. Of the 26 patients with successful cytogenetic studies, ten (28%) had unfavorable clonal chromosomal abnormalities (four Philadelphia chromosome, six others). A high complete remission (CR) rate (86%) was achieved. This was associated with delivery of 100% of the planned dosage of vincristine, prednisone, and daunorubicin at induction. Dose reduction of asparaginase, the fourth drug in the induction protocol, was recorded in 20 (40%) patients. The CR rate of these patients was not adversely affected. Dose reduction was recorded during consolidation (38 of 43 remitters) and maintenance (18 of 20 remitters) as a result of treatment toxicity. The mean received dose of teniposide, Ara-C, asparaginase, mercaptopurine, and methotrexate was 73% (SD 7%), 73% (SD 7%), 62% (SD 41%), 65% (SD 15%) and 73% (SD 17%) of the planned dosage, respectively. The 5-year overall survival and leukemia-free survival (LFS) were 11% (95% CI: 0-27%) and 13% (95% CI: 0-26%), respectively. Even standard-risk patients had 4-year LFS of only 26% (95% CI: 0-57%). Among 36 remitters not withdrawn from consolidation, there were 29 treatment failures after a median follow-up of 42 months; 25 (86%) of these were leukemia relapse, three (10%) were toxic death during consolidation, and one patient (4%) died from therapy-related myelodysplastic syndrome. We postulate inadequate drug delivery during postremission therapy contributed to the high relapse rate in the whole group as well as the standard-risk patients.
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PMID:Poor outcome of intensive chemotherapy for adult acute lymphoblastic leukemia: a possible dose effect. 776 60

The patient was initially diagnosed as having non-Hodgkin's lymphoma and was cured following treatment with prednisolone, vincristine, daunorubicin, 1-asparaginase, and cyclophosphamide. Seven years and two months later, he developed osteosarcoma in his right femur. He received chemotherapy consisting of methotrexate, carboplatin, etoposide, and ifosfamide and again obtained remission. After 2 years and 7 months, however, he was found to have pancytopenia with morphological abnormalities in the erythroid and myeloid series. Diagnosis of myelodysplastic syndrome (MDS) was made. Cytogenetic analysis of bone marrow cells revealed -5 and -7, which is typical for secondary MDS. This is a rare case of third malignancy presumably caused by alkylating agents.
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PMID:Myelodysplastic syndrome presenting as third malignancy after non-Hodgkin's lymphoma and osteosarcoma. 906 80

The major established cause of acute myeloid leukemia (AML) in the young is cancer chemotherapy. There are two forms of treatment-related AML (t-AML). Each form has a de novo counterpart. Alkylating agents cause t-AML characterized by antecedent myelodysplasia, a mean latency period of 5-7 years and complete or partial deletion of chromosome 5 or 7. The risk is related to cumulative alkylating agent dose. Germline NF-1 and p53 gene mutations and the GSTT1 null genotype may increase the risk. Epipodophyllotoxins and other DNA topoisomerase II inhibitors cause leukemias with translocations of the MLL gene at chromosome band 11q23 or, less often, t(8;21), t(3;21), inv(16), t(8;16), t(15;17) or t(9;22). The mean latency period is about 2 years. While most cases are of French-American-British (FAB) M4 or FAB M5 morphology, other FAB AML subtypes, myelodysplastic syndrome (MDS), acute lymphoblastic leukemia (ALL) and chronic myelogenous leukemia (CML) occur. Between 2 and 12% of patients who receive epipodophyllotoxin have developed t-AML. There is no relationship with higher cumulative epipodophyllotoxin dose and genetic predisposition has not been identified, but weekly or twice-weekly schedules and preceding l-asparaginase administration may potentiate the risk. The translocation breakpoints in MLL are heterogeneously distributed within a breakpoint cluster region (bcr) and the MLL gene translocations involve one of many partner genes. DNA topoisomerase II cleavage assays demonstrate a correspondence between DNA topoisomerase II cleavage sites and the translocation breakpoints. DNA topoisomerase II catalyzes transient double-stranded DNA cleavage and rejoining. Epipodophyllotoxins form a complex with the DNA and DNA topoisomerase II, decrease DNA rejoining and cause chromosomal breakage. Furthermore, epipodophyllotoxin metabolism generates reactive oxygen species and hydroxyl radicals that could create abasic sites, potent position-specific enhancers of DNA topoisomerase II cleavage. One proposed mechanism for the translocations entails chromosomal breakage by DNA topoisomerase II and recombination of DNA free ends from different chromosomes through DNA repair. With few exceptions, treatment-related leukemias respond less well to either chemotherapy or bone marrow transplantation than their de novo counterparts, necessitating more innovative treatments, a better mechanistic understanding of the pathogenesis, and strategies for prevention.
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PMID:Secondary leukemias induced by topoisomerase-targeted drugs. 974 98

This study was designed to test the hypothesis that high-dose asparaginase consolidation therapy improves survival in pediatric patients with T cell acute lymphoblastic leukemia and advanced stage lymphoblastic lymphoma. Five hundred and fifty-two patients (357 patients with T cell acute lymphoblastic leukemia (ALL) and 195 patients with advanced stage lymphoblastic lymphoma) were enrolled in POG study 8704 (T-3). Treatment included rotating combinations of high-dose myelosuppressive chemotherapy agents proven to be effective in T cell ALL in other POG group-wide or local institutional protocols (including vincristine, doxorubicin, cyclophosphamide, prednisone, asparaginase, teniposide, cytarabine and mercaptopurine). After achieving a complete remission (CR), patients were randomized to receive or not receive high-dose intensive asparaginase consolidation (25,000 IU/m2) given weekly for 20 weeks by intramuscular injection. Intrathecal chemotherapy (methotrexate, hydrocortisone and cytarabine) was given to prevent CNS disease, and CNS irradiation was used only for patients with leukemia and an initial WBC of >50,000/microl or patients with active CNS disease at diagnosis. CR was achieved in 96% of patients. The high-dose asparaginase regimen was significantly superior to the control regimen for both the leukemia and lymphoma subgroups. Four-year continuous complete remission rate (CCR) for the leukemia patients was 68% (s.e. 4%) with asparaginase as compared to 55% (s.e. 4%) without. For the lymphoma patients, 4-year CCR was 78% (s.e. 5%) with asparaginase and 64% (s.e. 6%) in the controls. The overall one-sided logrank test had a P value <0.001 favoring asparaginase, while corresponding values were P = 0.002 for ALL and P = 0.048 lymphoblastic lymphoma. Toxicities were tolerable, but there were 18 failures due to secondary malignancies (16 with non-lymphocytic leukemia or myelodysplasia). Neither WBC at diagnosis (leukemia patients) nor lymphoma stage were major prognostic factors. We conclude that when added to a backbone of effective rotating agents, repeated doses of asparaginase during early treatment improve the outcome for patients with T cell leukemia and advanced stage lymphoblastic lymphoma.
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PMID:Intensive high-dose asparaginase consolidation improves survival for pediatric patients with T cell acute lymphoblastic leukemia and advanced stage lymphoblastic lymphoma: a Pediatric Oncology Group study. 1008 23

Among 511 patients with therapy-related myelodysplastic syndrome or acute leukemia (t-MDS/t-AL) and balanced chromosome aberrations, 162 (32%) had translocations involving 11q23. The recurring translocation partners were 9p22 (48%), 19p13.3 (11%), 19p13.1 (10%), 4q21 (9%), 6q27 (6%), 1p32 (2%), 16p13.1 (2%), 10p13 (1%), and 17q25 (1%); in 9%, the translocations were seen only once. The remaining 349 patients were divided into five subgroups based on the balanced aberration: 21q22, inv(16), t(15;17), Rare, and Unique aberrations. Patients in the 11q23 subgroup had a sole cytogenetic abnormality more often than those in the 21q22, inv(16), Rare, and Unique subgroups, and a complex karyotype or -5/del(5q) and/or -7/del(7q) less often than patients in the 21q22, Rare, and Unique subgroups. Clinically, 11q23 patients had acute lymphoblastic leukemia (ALL) more often as their primary disease and a shorter latency from start of treatment for the primary disease to their t-MDS/t-AL diagnosis, except when compared with the inv(16) subgroup. The 11q23 subgroup demonstrated a younger age at t-MDS/t-AL diagnosis, but this finding was not significant when patients with AL as their primary diagnosis were excluded. Survival from the time of diagnosis of t-MDS/t-AL was significantly shorter for the 11q23 subgroup compared with that of the 21q22, inv(16), and t(15;17) subgroups (median 8 vs. 14, 28, and 29 months, respectively). Inferior survival occurred even though 11q23 patients were younger and more often received blood or marrow transplantation (BMT). Even among patients receiving BMT, 11q23 patients had a shorter median survival (9 vs. 12-31 months for the other subgroups). However, among 11q23 patients, those receiving BMT survived longer, with 1- and 5-year survivals of 43% and 18% compared with 23% and 7% for patients not transplanted. With regard to prior therapy, 11q23 patients, compared with other patients, received radiotherapy less often as their sole therapy and chemotherapy more often. They had received VP16, methotrexate, 6MP/6TG, L-asparaginase, daunorubicin, cytarabine, and VM26 more often, likely attributed to the high frequency of AL as their primary disease. More patients in the 11q23 subgroup had received doxorubicin, except in comparison with the 21q22 subgroup; more vincristine, except in comparison with the Rare and Unique subgroups; and more prednisone, except in comparison with the Unique subgroup. Patients in the 11q23 subgroup more often received alkylating agents (AAs) (86% vs. 59-82% for the other subgroups), and topoisomerase II inhibitors (TIs) (84% vs. 49-75%), and they more often reported exposure to AAs plus TIs without radiotherapy (33% vs. 12-21%), except in comparison with the 21q22 subgroup (36%). We performed a multivariate analysis to determine whether the adverse survival of 11q23 patients compared to other Workshop patients was explained by factors other than the presence of the 11q23 abnormality. Covariates in the final model were the five cytogenetic subgroup indicators, where the 11q23 subgroup was the referent (P < 0.0001); age at t-MDS/t-AL (P = 0.0036); previous exposure to lomustine (P < 0.0001) and mitoxantrone (P = 0.0225); BMT for t-MDS/t-AL (P = 0.0006); and karyotype complexity (P = 0.0114). The risk of death for 11q23 patients relative to patients in the 21q22, inv(16), t(15;17), and Unique subgroups was significant, even after adjustment for other risk factors (relative risks 2.3, 3.6, 3.1, and 1.5, respectively; P < 0.0001 for the first three comparisons and P = 0.0125 for the last). When a multivariable model was constructed, excluding patients with AL or MDS as their primary diagnosis, the relative risk of death for 11q23 patients was significantly higher than that of all five other cytogenetic subgroups. We conclude that among t-MDS/t-AL patients with balanced aberrations, 11q23 translocations are an independent adverse risk factor. Although BMT is the current therapy of choice, new treatment is required.
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PMID:11q23 balanced chromosome aberrations in treatment-related myelodysplastic syndromes and acute leukemia: report from an international workshop. 1192 Dec 71

We report on a nested case-control study with 328 cases with second malignant neoplasm (SMN) following childhood cancer and 639 matched controls based on the German Childhood Cancer Registry. In the adjusted overall analysis, the odds ratio (OR) for SMN following any radiotherapy or chemotherapy is 2.1 [95% confidence interval (CI): 1.8-3.3] and 1.8 (95% CI: 0.98-3.1), respectively. The strongest effect is seen for alkylating agents (OR=2.0, 95% CI: 1.2-3.3). The risk of SMN after leukemia is pronounced for antimetabolites (OR=17.2, 95% CI: 1.7-177) and asparaginase (OR=4.3, 95% CI: 1.7-11.0). Following solid tumors, the greatest effect is seen for platinum derivatives (OR=4.1, 95% CI: 1.7-10.1). For anthracyclines, a decreased risk is observed (OR=0.3, 95% CI: 0.1-0.6). Secondary solid tumors are mainly associated with radiotherapy (OR=4.5, 95% CI: 2.5-8.0), especially secondary carcinomas. Secondary acute myeloid leukemia and myelodysplastic syndrome are mainly associated with alkylating agents (OR=8.5, 95% CI: 0.97-74.8), asparaginase (OR=6.8, 95% CI: 2.3-20.6), and platinum derivatives (OR=4.5, 95% CI: 1.5-13.6). The observed risks are in many instances lower than the ones published in previous studies relating to earlier treatment eras of the primary diseases. These differences may be attributed to less toxic but still effective treatment regimes but also to differences in the length of follow-up.
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PMID:Case-control study on the therapy of childhood cancer and the occurrence of second malignant neoplasms in Germany. 1926 32