Nobuko Hijiya

Clinical significance of minimal residual disease in childhood acute lymphoblastic leukemia after first relapse.

Using flow cytometric techniques capable of detecting 0.01% leukemic cells, we prospectively studied minimal residual disease (MRD) in patients with acute lymphoblastic leukemia (ALL) after first relapse. At the end of remission reinduction, 41 patients had a bone marrow sample adequate for MRD studies; 35 of these were in morphologic remission. Of the 35 patients, 19 (54%) had MRD ⩾0.01%, a finding that was associated with subsequent leukemia relapse. The 2-year cumulative incidence of second leukemia relapse was 70.2±12.3% for the 19 MRD-positive patients and 27.9±12.4% for the 16 MRD-negative patients (P=0.008). Among patients with a first relapse off therapy, 2-year second relapse rates were 49.1±17.8% in the 12 MRD-positive and 0% in the 11 MRD-negative patients (P=0.014); among those who received only chemotherapy after first relapse, the 2-year second relapse rates were 81.5±14.4% (n=12) and 25.0±13.1% (n=13), respectively (P=0.004). Time of first relapse and MRD were the only two significant predictors of outcome in a multivariate analysis. We conclude that MRD assays should be used to guide the selection of postremission therapy in patients with ALL in first relapse.

Female Reproductive Health After Childhood, Adolescent, and Young Adult Cancers: Guidelines for the Assessment and Management of Female Reproductive Complications

PURPOSE As more young female patients with cancer survive their primary disease, concerns about reproductive health related to primary therapy gain relevance. Cancer therapy can often affect reproductive organs, leading to impaired pubertal development, hormonal regulation, fertility, and sexual function, affecting quality of life. METHODS The Childrens Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancer (COG-LTFU Guidelines) are evidence-based recommendations for screening and management of late effects of therapeutic exposures. The guidelines are updated every 2 years by a multidisciplinary panel based on current literature review and expert consensus. RESULTS This review summarizes the current task force recommendations for the assessment and management of female reproductive complications after treatment for childhood, adolescent, and young adult cancers. Experimental pretreatment as well as post-treatment fertility preservation strategies, including barriers and ethical considerations, which are not included in the COG-LTFU Guidelines, are also discussed. CONCLUSION Ongoing research will continue to inform COG-LTFU Guideline recommendations for follow-up care of female survivors of childhood cancer to improve their health and quality of life.

Male Reproductive Health After Childhood, Adolescent, and Young Adult Cancers: A Report From the Children's Oncology Group

The majority of children, adolescents, and young adults diagnosed with cancer will become long-term survivors. Although cancer therapy is associated with many adverse effects, one of the primary concerns of young male cancer survivors is reproductive health. Future fertility is often the focus of concern; however, it must be recognized that all aspects of male health, including pubertal development, testosterone production, and sexual function, can be impaired by cancer therapy. Although pretreatment strategies to preserve reproductive health have been beneficial to some male patients, many survivors remain at risk for long-term reproductive complications. Understanding risk factors and monitoring the reproductive health of young male survivors are important aspects of follow-up care. The Childrens Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancer (COG-LTFU Guidelines) were created by the COG to provide recommendations for follow-up care of survivors at risk for long-term complications. The male health task force of the COG-LTFU Guidelines, composed of pediatric oncologists, endocrinologists, nurse practitioners, a urologist, and a radiation oncologist, is responsible for updating the COG-LTFU Guidelines every 2 years based on literature review and expert consensus. This review summarizes current task force recommendations for the assessment and management of male reproductive complications after treatment for childhood, adolescent, and young adult cancers. Issues related to male health that are being investigated, but currently not included in the COG-LTFU Guidelines, are also discussed. Ongoing investigation will inform future COG-LTFU Guideline recommendations for follow-up care to improve health and quality of life for male survivors.

Phase 2 trial of clofarabine in combination with etoposide and cyclophosphamide in pediatric patients with refractory or relapsed acute lymphoblastic leukemia

The outcomes in children with refractory/relapsed (R/R) acute lymphoblastic leukemia (ALL) are dismal. The efficacy and safety of intravenous clofarabine 40 mg/m(2) per day, cyclophosphamide 440 mg/m(2) per day, and etoposide 100 mg/m(2) per day for 5 consecutive days in pediatric patients with R/R ALL was evaluated in this phase 2 study. The primary endpoint was overall response rate (complete remission [CR] plus CR without platelet recovery [CRp]). Among the 25 patients (median age, 14 years; pre-B cell ALL, 84%; ≥ 2 prior regimens: 84%; refractory to previous regimen: 60%), the overall response rate was 44% (7 CR, 4 CRp) with a 67.3-week median duration or remission censored at last follow-up. Most patients proceeded to alternative therapy, and 10 patients (40%) received hematopoietic stem cell transplantation. Six patients (24%) died because of treatment-related adverse events associated with infection, hepatotoxicity, and/or multiorgan failure. The study protocol was amended to exclude patients with prior hematopoietic stem cell transplantation after 4 of the first 8 patients developed severe hepatotoxicity suggestive of veno-occlusive disease. No additional cases of veno-occlusive disease occurred. The regimen offered encouraging response rates and sustained remission in R/R patients. Future investigation should include exploration of patient selection, dosing, and supportive care. This trial was registered at www.clinicaltrials.gov as #NCT00315705.

Acute Leukemia as a Secondary Malignancy in Children and Adolescents: Current Findings and Issues

Secondary acute leukemia is a devastating complication in children and adolescents who have been treated for cancer. Secondary acute lymphoblastic leukemia (s‐ALL) was rarely reported previously but can be distinguished today from recurrent primary ALL by comparison of immunoglobulin and T‐cell receptor rearrangement. Secondary acute myeloid leukemia (s‐AML) is much more common, and some cases actually may be second primary cancers. Treatment‐related and host‐related characteristics and their interactions have been identified as risk factors for s‐AML. The most widely recognized treatment‐related risk factors are alkylating agents and topoisomerase II inhibitors (epipodophyllotoxins and anthracyclines). The magnitude of the risk associated with these factors depends on several variables, including the administration schedule, concomitant medications, and host factors. A high cumulative dose of alkylating agents is well known to predispose to s‐AML. The prevalence of alkylator‐associated s‐AML has diminished among pediatric oncology patients with the reduction of cumulative alkylator dose and limited use of the more leukemogenic alkylators. The best‐documented topoisomerase II inhibitor‐associated s‐AML is s‐AML associated with epipodophyllotoxins. The risk of s‐AML in these cases is influenced by the schedule of drug administration and by interaction with other antineoplastic agents but is not consistently found to be related to cumulative dose. The unpredictable risk of s‐AML after epipodophyllotoxin therapy may discourage the use of these agents, even in patients at a high risk of disease recurrence, although the benefit of recurrence prevention may outweigh the risk of s‐AML. Studies in survivors of adult cancers suggest that, contrary to previous beliefs, the outcome of s‐AML is not necessarily worse than that of de novo AML when adjusted for cytogenetic features. More studies are needed to confirm this finding in the pediatric patient population. Cancer 2009.

A multi-center phase I study of clofarabine, etoposide and cyclophosphamide in combination in pediatric patients with refractory or relapsed acute leukemia

This Phase I study of clofarabine with etoposide and cyclophosphamide for children with relapsed/refractory acute lymphoblastic leukemia (ALL) or acute myelogenous leukemia (AML) was conducted to determine the maximum tolerated dose (MTD), dose-limiting toxicities and the recommended phase 2 doses (RP2Ds). All three drugs were administered for five consecutive days in induction and four consecutive days in consolidation, for a maximum of eight cycles. A total of 25 patients (20 ALL and 5 AML) were enrolled in five cohorts. An MTD was not reached. The RP2Ds of clofarabine, cyclophosphamide and etoposide were 40, 440 and 100 mg/m2/day, respectively. Complete remission (CR) was achieved in 10 patients (ALL: nine; AML: one), and CR without platelet recovery in six patients (ALL: two; AML: four) for an overall response rate of 64% (ALL: 55%; AML: 100%). Of the 16 responders, 9 patients proceeded to hematopoietic stem cell transplantation. In conclusion, the combination of clofarabine, etoposide and cyclophosphamide was well tolerated and effective in pediatric patients with relapsed/refractory leukemia. Of note, the phase II portion of the trial was amended after the occurrence of unexpected hepatotoxicity. The ongoing phase II study will evaluate the efficacy and safety of this regimen in ALL patients.

Risk of Adverse Events After Completion of Therapy for Childhood Acute Lymphoblastic Leukemia

PURPOSE We studied the frequency, causes, and predictors of adverse events in children with acute lymphoblastic leukemia (ALL) who had completed treatment on contemporary clinical protocols between 1984 and 1999. Our goal was to use the information to further refine therapy and advance cure rates. METHODS Cumulative incidence functions of any post-treatment failure or any post-treatment relapse were estimated by the method of Kalbfleisch and Prentice and compared with Grays test. The Cox proportional hazards model was used to identify independent prognostic factors. RESULTS Of the 827 patients who completed all treatment while in initial complete remission, 134 patients subsequently had major adverse events, including 90 leukemic relapses, 40 second malignancies, and four deaths in remission. The cumulative incidence of any adverse event was 14.0% +/- 1.2% (SE) at 5 years and 16.9% +/- 1.4% at 10 years. The risk of any leukemic relapse was 10.0% +/- 1.1% at 5 years and 11.4% +/- 1.2% at 10 years. Male sex was the only independent predictor of relapse (hazard ratio, 1.74; 95% CI, 1.11 to 2.74; P = .02). CONCLUSION Further treatment refinements for children with ALL should aim not only to decrease the leukemic relapse rate, but also to reduce the risk of development of second malignancies.

Successive clinical trials for childhood acute myeloid leukemia at St Jude Children's Research Hospital, from 1980 to 2000

Despite substantial progress in the management of childhood acute myeloid leukemia (AML), only about 50% of patients are cured by intensive chemotherapy. The long-term results of clinical trials may reveal principles that can guide the development of future therapy. From 1980 to 2000, 251 patients <15 years of age with newly diagnosed AML were enrolled on one of the five consecutive St Jude AML studies. The median age of the 128 boys and 123 girls was 6.2 years; 193 were white, 45 black, and 13 of other racial groups. With the exception of one protocol (AML-83), outcomes improved in general over the two decades. The estimated 5-year event-free survival (±s.e.) was 30.8±5.6% for AML-80; 11.1±4.3% for AML-83; 35.9±7.4% for AML-87; 43.5±6.2% for AML-91; and 45.0±11.1% for AML-97. Resistant or relapsed AML caused the great majority of treatment failures. Increasing the intensity of chemotherapy (AML-87) did not improve outcome, partially because of toxicity, nor did prolonging postremission therapy by adding sequential myeloablative (AML-80) or nonmyeloablative (AML-83) chemotherapy cycles. We conclude that subtype-specific therapies are needed to replace the ‘one size fits all’ strategy of the past two decades.

Comparison of Native E. coli and PEG Asparaginase Pharmacokinetics and Pharmacodynamics in Pediatric Acute Lymphoblastic Leukemia

Asparaginase (ASP) is used routinely in frontline clinical trials for the treatment of childhood acute lymphoblastic leukemia (ALL). The goals of this study were to assess the pharmacokinetics and pharmacodynamics of ASP and to mathematically model the dynamics between ASP and asparagine (ASN) in relapsed ALL. Forty children were randomized to receive either native or polyethylene glycolated (PEG) Escherichia coli ASP during reinduction therapy. Serial plasma ASP and ASN, cerebrospinal fluid (CSF) ASN, and serum anti‐ASP antibody samples were collected. The ASP clearance was higher (P = 0.001) for native vs. PEG ASP. Patients with antibodies to PEG ASP had faster PEG ASP clearance (P = 0.004) than did antibody‐negative patients. Patients who were positive for antibodies had higher CSF ASN concentrations than did those who were negative (P = 0.04). The modeling suggests that by modifying dosages, comparable ASN depletion is achievable with both preparations. At relapse, there were significant pharmacokinetic and pharmacodynamic differences attributable to ASP preparation and antibody status.

Effective treatment of advanced-stage childhood lymphoblastic lymphoma without prophylactic cranial irradiation: Results of St Jude NHL13 study

There has been a steady improvement in cure rates for children with advanced-stage lymphoblastic non-Hodgkins lymphoma. To further improve cure rates whereas minimizing long-term toxicity, we designed a protocol (NHL13) based on a regimen for childhood T-cell acute lymphoblastic leukemia, which features intensive intrathecal chemotherapy for central –nervous system-directed therapy and excludes prophylactic cranial irradiation. From 1992 to 2002, 41 patients with advanced-stage lymphoblastic lymphoma were enrolled on the protocol. Thirty patients had stage III and 11 had stage IV disease. Thirty-three cases had a precursor T-cell immunophenotype, five had precursor B-cell immunophenotype and in three immunophenotype was not determined. Out of the 41 patients, 39 (95%) achieved a complete remission. The 5-year event-free rate was 82.9±6.3% (s.e.), and 5-year overall survival rate was 90.2±4.8% (median follow-up 9.3 years (range 4.62–13.49 years)). Adverse events included two induction failures, one death from typhlitis during remission, three relapses and one secondary acute myeloid leukemia. The treatment described here produces high cure rates in children with lymphoblastic lymphoma without the use of prophylactic cranial irradiation.