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Dive into the research topics where Amy L. Billett is active.

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Featured researches published by Amy L. Billett.


Journal of Clinical Oncology | 2005

Phase II Study of Nelarabine (compound 506U78) in Children and Young Adults With Refractory T-Cell Malignancies: A Report From the Children’s Oncology Group

Stacey L. Berg; Susan M. Blaney; Meenakshi Devidas; Tom A. Lampkin; Anthony J. Murgo; Mark Bernstein; Amy L. Billett; Joanne Kurtzberg; Greg Reaman; Paul S. Gaynon; James A. Whitlock; Mark Krailo; Michael B. Harris

PURPOSE Nelarabine (compound 506U78), a water soluble prodrug of 9-b-d-arabinofuranosylguanine, is converted to ara-GTP in T lymphoblasts. We sought to define the response rate of nelarabine in children and young adults with refractory or recurrent T-cell disease. PATIENTS AND METHODS We performed a phase II study with patients stratified as follows: stratum 1: > or = 25% bone marrow blasts in first relapse; stratum 2: > or = 25% bone marrow blasts in > or = second relapse; stratum 3: positive CSF; stratum 4: extramedullary (non-CNS) relapse. The initial nelarabine dose was 1.2 g/m2 daily for 5 consecutive days every 3 weeks. There were two dose de-escalations due to neurotoxicity on this or other studies. The final dose was 650 mg/m2/d for strata 1 and two patients and 400 mg/m2/d for strata 3 and four patients. RESULTS We enrolled 121 patients (106 assessable for response) at the final dose levels. Complete plus partial response rates at the final dose levels were: 55% in stratum 1; 27% in stratum 2; 33% in stratum 3; and 14% in stratum 4. There were 31 episodes of > or = grade 3 neurologic adverse events in 27 patients (18% of patients). CONCLUSION Nelarabine is active as a single agent in recurrent T-cell leukemia, with a response rate more than 50% in first bone marrow relapse. The most significant adverse events associated with nelarabine administration are neurologic. Further studies are planned to determine whether the addition of nelarabine to front-line therapy for T-cell leukemia in children will improve survival.


Journal of Clinical Oncology | 2007

Final Results of a Prospective Clinical Trial With VAMP and Low-Dose Involved-Field Radiation for Children With Low-Risk Hodgkin's Disease

Sarah S. Donaldson; Michael P. Link; Howard J. Weinstein; Shesh N. Rai; Sam Brain; Amy L. Billett; Craig A. Hurwitz; Matthew J. Krasin; Larry E. Kun; Karen C. Marcus; Nancy J. Tarbell; Jeffrey A. Young; Melissa M. Hudson

PURPOSE To evaluate outcome and assess complications in children and adolescents with low-risk Hodgkins disease treated with vinblastine, doxorubicin, methotrexate, and prednisone (VAMP) chemotherapy and low-dose, involved-field radiation therapy (IFRT). PATIENTS AND METHODS One hundred ten children with low-risk Hodgkins disease were treated with four cycles of VAMP and 15 Gy IFRT for those who achieved a complete response (CR) or 25.5 Gy for those with a partial response after two cycles of VAMP. RESULTS With median follow-up of 9.6 years (range, 1.7 to 15.0), 5- and 10-year overall survival were 99.1% and 96.1%, respectively, and 5-and 10-year event-free survival (EFS) were 92.7% and 89.4%. Factors contributing to 10-year EFS were: early CR (P = .02), absence of B symptoms (P = .01), lymphocyte predominant histologic subtype (P = .04), and less than three initial sites of disease (P = .02). Organ toxicity has been limited to correctable hypothyroidism in 42% of irradiated patients, and one case of cardiac dysfunction. Seventeen healthy babies have been born to 106 survivors. There have been two malignant tumors: one thyroid cancer within the radiation therapy field and one Ewings sarcoma outside the radiation therapy field. CONCLUSION Risk-adapted, combined-modality therapy using VAMP chemotherapy with radiation is effective and well tolerated. Pediatric patients with low-risk Hodgkins disease can be cured with therapy without an alkylating agent, bleomycin, etoposide, or high-dose, extended-field radiotherapy. Thus, these children are expected to retain normal fertility, organ function, and be at low risk of a second malignant tumor.


Journal of Clinical Oncology | 2002

VAMP and Low-Dose, Involved-Field Radiation for Children and Adolescents With Favorable, Early-Stage Hodgkin’s Disease: Results of a Prospective Clinical Trial

Sarah S. Donaldson; Melissa M. Hudson; Kathleen R. Lamborn; Michael P. Link; Larry E. Kun; Amy L. Billett; Karen C. Marcus; Craig A. Hurwitz; Jeffrey A. Young; Nancy J. Tarbell; Howard J. Weinstein

PURPOSE To evaluate outcome and assess toxicity of children and adolescents with early-stage, favorable Hodgkins disease treated with vinblastine, doxorubicin, methotrexate, and prednisone (VAMP) and low-dose, involved-field radiation. PATIENTS AND METHODS One hundred ten patients with clinical stages I and II, favorable (nonbulky) Hodgkins disease were treated with four cycles of VAMP chemotherapy and 15 Gy involved-field radiation for those who achieved a complete response, or 25.5 Gy for those who achieved a partial response to two cycles of VAMP. RESULTS With a median follow-up of 5.6 years (range, 1.1 to 10.4 years), the 5-year survival and event-free survival were 99% (lower confidence limit [CL], 97.4%) and 93% (lower CL, 88.6%), respectively. Factors associated with event-free survival of 100% were complete response to two cycles of VAMP and histology other than nodular sclerosing Hodgkins disease (NSHD). No serious early or late toxicity has been observed. Patients presenting with clinical stages I and IIA, nonbulky disease involving fewer than three nodal sites have a projected survival and event-free survival of 100% and 97% (lower CL, 93%), respectively, at 5 years. CONCLUSION Risk-adapted, combined-modality therapy using only four cycles of VAMP chemotherapy with 15 to 25.5 Gy of involved-field radiation for patients with early-stage/favorable Hodgkins disease is highly effective and without demonstrable late effects. These results indicate that pediatric patients with stages I and II favorable Hodgkins disease can be cured with limited therapy that does not include an alkylating agent, bleomycin, etoposide, or high-dose, extended-field radiation therapy.


Journal of Clinical Oncology | 2003

Prognostic factors for children with Hodgkin's disease treated with combined-modality therapy.

Ron S. Smith; Qing Chen; Melissa M. Hudson; Michael P. Link; Larry E. Kun; Howard J. Weinstein; Amy L. Billett; Karen J. Marcus; Nancy J. Tarbell; Sarah S. Donaldson

PURPOSE Evaluation of pretreatment factors to identify children at high risk for relapse after combined-modality therapy for Hodgkins disease. PATIENTS AND METHODS From 1990 to 2000, 328 pediatric patients with clinical stage I to IV Hodgkins disease were treated with chemotherapy and low-dose involved-field radiotherapy on prospective, collaborative, risk-adapted protocols at three institutions. Pretreatment factors were analyzed by univariate and multivariate analysis for prognostic significance for 5-year disease-free survival (DFS) and overall survival (OS). RESULTS With a median follow-up of 59 months (range, 8 to 125 months), the 5-year DFS and OS for all patients were 83% and 93%, respectively. Several factors were associated with inferior DFS and OS by univariate analysis. By multivariate analysis, male sex; stage IIB, IIIB, or IV disease; bulky mediastinal disease; WBC more than 13.5 x 10(3)/mm3; and hemoglobin less than 11.0 g/dL were significant for inferior DFS. A prognostic index was developed incorporating the five significant factors from the multivariate analysis, assigning each a score of 1. The 5-year DFS and OS for children with a prognostic score of 0 to 1 were 94% and 99%; score 2, 85% and 96%; score 3, 71% and 92%; and score 4 or 5, 49% and 72%, respectively. There was a significant difference in DFS among each of these groups, with significantly worse OS in those with a score of 4 to 5. CONCLUSION A prognostic index that was based on five pretreatment factors correlated with inferior DFS by multivariate analysis stratified patients by outcome; this may be useful in assigning children with Hodgkins disease to risk-adapted therapy.


Neurosurgery | 2001

Memory deficits among children with craniopharyngiomas.

Sarah C. Carpentieri; Deborah P. Waber; R. Michael Scott; Liliana Goumnerova; Mark W. Kieran; Laurie E. Cohen; Francine Kim; Amy L. Billett; Nancy J. Tarbell; Scott L. Pomeroy

OBJECTIVETo describe neuropsychological functioning (with a specific focus on cognition and memory) after surgical treatment of craniopharyngiomas. METHODSSixteen patients who were between 6 and 15 years of age at the time of surgery comprised the sample. Each child had been treated for a craniopharyngioma with surgery only, on Dana-Farber Cancer Institute Protocol 92-077. RESULTSThe overall level of cognitive functioning was well within the average range, with both language and visuospatial functioning being generally intact; however, specific memory problems, in both the language and visuospatial domains, were evident. CONCLUSIONAlthough general cognitive functioning was intact after the surgical treatment of craniopharyngiomas, difficulties in the retrieval of learned information were observed. Neuropsychological assessments, with a focus on memory recall, should be a component of the medical management plan for each child.


Leukemia | 2000

Incidence and prognostic significance of MDM2 oncoprotein overexpression in relapsed childhood acute lymphoblastic leukemia

Muxiang Zhou; Lubing Gu; Thomas C. Abshire; Alan Homans; Amy L. Billett; Andrew M. Yeager; Harry W. Findley

MDM2 overexpression by pediatric ALL cells at initial diagnosis has been linked to poor response to therapy. In the present study, we evaluated the incidence of MDM2 overexpression by ALL cells from pediatric patients at first relapse and compared MDM2 protein levels with in vitro response to adriamycin and with duration of initial complete remission (CR1). Since an important role of MDM2 in enhancing cell proliferation and survival appears to be inhibition of p53 activity, we also evaluated the status of p53 in these patients’ leukemic cells. MDM2 protein levels were determined by Western blot analysis of leukemic bone marrow cells obtained from 42 patients with B cell precursor (BCP) ALL who relapsed during or following therapy on standard POG ALL protocols. Twelve of 42 (29%) cases have MDM2 levels ⩾10-fold higher than those detected in normal bone marrow mononuclear (NMMC) cells, which express relatively low levels of protein. Thirty cases (71%) expressed MDM2 at levels <10-fold those in nmmc, including 24 mdm2-negative cases (57%). P53 mutations were detected by single-strand conformation polymorphism analysis in two cases. Overexpression of mdm2 (⩾10-fold) was significantly correlated with adriamycin resistance and decreased duration of cr1. Eight of 12 (75%) overexpressers showed high levels of in vitro resistance to adriamycin, compared to four of 30 (13%) non-overexpressers (P < 0.005). The median cr1 for mdm2 overexpressers was 20.5 months (range: 3–75 months) compared to 41 months (range: 8–98 months) for non-overexpressers (P < 0.01). Four of 42 patients failed to achieve cr following re-induction: leukemic cells from three of these patients either overexpressed mdm2 or contained a mutant p53. These results indicate that overexpression of mdm2 plays a significant role in refractory pediatric all and is associated with early relapse, adriamycin resistance, and failure to respond to re-induction therapy.


International Journal of Radiation Oncology Biology Physics | 1997

Childhood optic chiasm gliomas: Radiographic response following radiotherapy and long-term clinical outcome

May L. Tao; Patrick D. Barnes; Amy L. Billett; Traci Leong; Dennis C. Shrieve; R. Michael Scott; Nancy J. Tarbell

PURPOSE In children with chiasmal gliomas, radiation therapy can arrest progressive visual and neurologic impairment. We examined the radiographic response and clinical outcomes after irradiation. METHODS AND MATERIALS Forty-two children (median age at diagnosis, 6.6 years) with chiasmal gliomas were managed as follows: 11 asymptomatic patients with neurofibromatosis-1 (NF-1) were observed only; 2 patients, less than 3 years old, underwent surgery and chemotherapy to delay irradiation; and 29 patients with progressive disease received radiation with or without prior surgery or chemotherapy. Time to radiographic response, long-term tumor control and late sequelae were reviewed for the 29 irradiated patients. RESULTS The probability of at least 50% radiographic response at 24 months after irradiation was 18.1% and increased to 38.2% by 48 months and 45.9% by 60 months. By actuarial analysis, the median time for such radiographic response was 62 months. For the 29 irradiated patients, the 10-year freedom from progression and overall survival rates were 100% and 89%, respectively (median follow-up for surviving patients, 108 months). Stabilization or improvement in vision occurred in 81% of 26 evaluable irradiated patients. CONCLUSIONS Notable radiographic response may be observed years after irradiation. Radiation therapy provides excellent long-term tumor control and vision preservation or improvement in the majority of patients with progressive chiasmal gliomas.


Journal of Clinical Oncology | 1989

Autologous bone marrow transplantation for acute lymphoblastic leukemia.

Stephen E. Sallan; Niemeyer Cm; Amy L. Billett; Jeffrey M. Lipton; Nancy J. Tarbell; Richard D. Gelber; Christine Murray; T P Pittinger; L C Wolfe; Robert C. Bast

Forty-four children with acute lymphoblastic leukemia (ALL) who had relapsed (N = 43) or had refractory disease (N = 1) were intensively treated with combination chemotherapy, had remission bone marrow (BM) harvested and purged in vitro with monoclonal antibodies specific for leukemia-associated antigens, underwent postharvest ablative chemotherapy and radiotherapy and subsequently were infused with their autologous marrow. Of the 44 patients treated between November 1980 and January 1988, 19 relapsed, 10 died of complications, and 15 remained in complete remission for a median of 28.5 months (range, 10+ to 94+). Event-free survival (EFS) (+/- SE) at 5 years after autologous transplantation was 29 +/- 8%. For the 26 patients whose initial remission was greater than 2 years, event-free survival was 51 +/- 10%. These results compare favorably with allogeneic transplantation and chemotherapy trials for patients with relapsed ALL, and provide an alternative transplantation option for children without histocompatible donors.


Journal of Clinical Oncology | 2006

Isolated CNS Relapse of Acute Lymphoblastic Leukemia Treated With Intensive Systemic Chemotherapy and Delayed CNS Radiation: A Pediatric Oncology Group Study

Julio C. Barredo; Meenakshi Devidas; Stephen J. Lauer; Amy L. Billett; Maryanne H. Marymont; Jeanette Pullen; Bruce M. Camitta; Naomi J. Winick; William L. Carroll; A. Kim Ritchey

PURPOSE Prognosis and outcome of children with isolated CNS relapse of acute lymphoblastic leukemia (ALL) has depended on duration of first complete remission (CR1). This study intensified systemic therapy by delaying CNS radiation for 12 months and tailored CNS radiation by CR1 duration. PATIENTS AND METHODS Seventy-six children with first isolated CNS relapse of ALL were treated with systemic chemotherapy that effectively penetrates into the CSF and intrathecal chemotherapy for 12 months. Patients with CR1 of less than 18 months received craniospinal radiation (24 Gy cranial/15 Gy spinal), whereas those with CR1 of 18 months or more received cranial radiation only (18 Gy), followed by maintenance chemotherapy. Additionally, asymptomatic patients were enrolled in a thiotepa up-front therapeutic window. RESULTS Seventy-four (97.4%) of 76 eligible patients achieved a second remission. Overall 4-year event-free survival (EFS) for the 71 precursor B-cell patients was 70.1% +/- 5.8%. CR1 duration and National Cancer Institute (NCI; National Institutes of Health, Bethesda, MD) risk group at initial diagnosis predicted outcome. Patients with CR1 of less than 18 months and 18 months or more had a 4-year EFS of 51.6% +/- 11.3% and 77.7% +/- 6.4% (P = .027), respectively. NCI high- versus standard-risk 4-year EFS was 51.4% +/- 10.8% and 80.2% +/- 6.3% (P = .0018), respectively. A significant difference in EFS between standard risk/CR1 of at least 18 months and both high risk/CR1 of less than 18 months and high risk/CR1 of at least 18 months groups was detected (P = .0068 and .0314, respectively). Response rate to thiotepa was 78%. Most relapses involved the bone marrow, and three second malignancies were reported. CONCLUSION Twelve months of intensive systemic chemotherapy with reduced dose cranial radiation (18 Gy) is highly effective for children with isolated CNS relapse and CR1 of 18 months or more. Novel strategies are needed for patients with CR1 of less than 18 months.


JAMA | 2012

Association Between Radiotherapy vs No Radiotherapy Based on Early Response to VAMP Chemotherapy and Survival Among Children With Favorable-Risk Hodgkin Lymphoma

Monika L Metzger; Howard J. Weinstein; Melissa M. Hudson; Amy L. Billett; Eric C. Larsen; Alison M. Friedmann; Scott C. Howard; Sarah S. Donaldson; Matthew J. Krasin; Larry E. Kun; Karen J. Marcus; Torunn I. Yock; Nancy J. Tarbell; Catherine A. Billups; Jianrong Wu; Michael P. Link

CONTEXT More than 90% of children with favorable-risk Hodgkin lymphoma can achieve long-term survival, yet many will experience toxic effects from radiation therapy. Pediatric oncologists strive for maintaining excellent cure rates while minimizing toxic effects. OBJECTIVE To evaluate the efficacy of 4 cycles of vinblastine, Adriamycin (doxorubicin), methotrexate, and prednisone (VAMP) in patients with favorable-risk Hodgkin lymphoma who achieve a complete response after 2 cycles and do not receive radiotherapy. DESIGN, SETTING, AND PATIENTS Multi-institutional, unblinded, nonrandomized single group phase 2 clinical trial to assess the need for radiotherapy based on early response to chemotherapy. Eighty-eight eligible patients with Hodgkin lymphoma stage I and II (<3 nodal sites, no B symptoms, mediastinal bulk, or extranodal extension) enrolled between March 3, 2000, and December 9, 2008. Follow-up data are current to March 12, 2012. INTERVENTIONS The 47 patients who achieved a complete response after 2 cycles received no radiotherapy, and the 41 with less than a complete response were given 25.5 Gy-involved-field radiotherapy. MAIN OUTCOME MEASURES Two-year event-free survival was the primary outcome measure. A 2-year event-free survival of greater than 90% was desired, and 80% was considered to be unacceptably low. RESULTS Two-year event-free survival was 90.8% (95% CI, 84.7%-96.9%). For patients who did not require radiotherapy, it was 89.4% (95% CI, 80.8%-98.0%) compared with 92.5% (95% CI, 84.5%-100%) for those who did (P = .61). Most common acute adverse effects were neuropathic pain (2% of patients), nausea or vomiting (3% of patients), neutropenia (32% of cycles), and febrile neutropenia (2% of patients). Nine patients (10%) were hospitalized 11 times (3% of cycles) for febrile neutropenia or nonneutropenic infection. Long-term adverse effects after radiotherapy were asymptomatic compensated hypothyroidism in 9 patients (10%), osteonecrosis and moderate osteopenia in 2 patients each (2%), subclinical pulmonary dysfunction in 12 patients (14%), and asymptomatic left ventricular dysfunction in 4 patients (5%). No second malignant neoplasms were observed. CONCLUSIONS Among patients with favorable-risk Hodgkin lymphoma and a complete early response to chemotherapy, the use of limited radiotherapy resulted in a high rate of 2-year event-free survival. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00145600.

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Michael P. Link

Lucile Packard Children's Hospital

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Stephen E. Sallan

University of Colorado Denver

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Larry E. Kun

Medical College of Wisconsin

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Aditya H. Gaur

St. Jude Children's Research Hospital

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