Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Robert S. Lavey is active.

Publication


Featured researches published by Robert S. Lavey.


International Journal of Radiation Oncology Biology Physics | 2001

Impact of hemoglobin level and use of recombinant erythropoietin on efficacy of preoperative chemoradiation therapy for squamous cell carcinoma of the oral cavity and oropharynx

Christoph Glaser; Werner Millesi; Gabriela Kornek; Susanna Lang; Birgit Schüll; Franz Watzinger; Edgar Selzer; Robert S. Lavey

PURPOSE We assessed the influence of hemoglobin level and r-HuEPO administration on response to chemoradiotherapy, locoregional tumor control, and overall survival in patients treated with neoadjuvant chemoradiotherapy and surgery for a squamous cell carcinoma of the oral cavity or oropharynx. METHODS AND MATERIALS The 191 study patients were treated with mitomycin C (15 mg/m(2) day 1), 5-fluorouracil (750 mg/m(2)/day, days 1-5), and radiotherapy (50 Gy in 25 fractions weeks 1-5), followed by resection of the primary tumor bed and neck dissection at the General Hospital Vienna, Austria, between November 1989 and October 1998 for a T2-4, N0-3, M0 SCC of the oral cavity or oropharynx. Starting in May 1996, patients with a low hemoglobin (Hgb) before or during chemoradiotherapy received r-HuEPO 10,000 IU/kg s.c. 3-6 times/week until the week of surgery. RESULTS On multivariate analysis, Hgb level and use of r-HuEPO were independent prognostic factors for response to chemoradiotherapy and locoregional tumor control (p < 0.01). Pathologic response to neoadjuvant therapy was also predictive of locoregional control (p < 0.001). Patients with a pretreatment Hgb > or = 14.5 g/dL had significantly higher complete response, locoregional control, and survival rates than the patients with a pretreatment Hgb < 14.5 g/dL who did not receive r-HuEPO (p < 0.05). The response, control, and survival rates in patients with a pretreatment Hgb < 14.5 g/dL given r-HuEPO were significantly higher than in low Hgb patients not given r-HuEPO (p < or = 0.001) and equivalent to patients with a pretreatment Hgb > 14.5 g/dL (p > or = 0.3). CONCLUSION Low pretreatment Hgb is a negative prognostic factor for oral cavity and oropharyngeal SCCA patients, but was completely abrogated by r-HuEpo administration during neoadjuvant chemoradiotherapy. Randomized trials of radiation and/or chemotherapy with or without r-HuEPO for patients whose Hgb level is either low at the start of therapy or is anticipated to become low during therapy are indicated.


International Journal of Radiation Oncology Biology Physics | 2000

Severe anemia is associated with poor tumor oxygenation in head and neck squamous cell carcinomas.

Axel Becker; Peter Stadler; Robert S. Lavey; Gabriele Hänsgen; Thomas Kuhnt; Christine Lautenschläger; Horst Feldmann; Michael Molls; Jürgen Dunst

PURPOSE To investigate the relationship between tumor oxygenation and the blood hemoglobin (Hb) concentration in patients with squamous cell carcinoma of the head and neck (SCCHN). METHODS AND MATERIALS A total of 133 patients with SCCHN underwent pretreatment polarographic pO2 measurements of their tumors. In 66 patients measurements were also made in sternocleidomastoid muscles. The patients were divided into three groups according to their Hb concentration-severe anemia (Hb < 11.0 g/dl), mild anemia (female: Hb 11.0-11.9 g/dl; male: Hb 11.0-12.9 g/dl), and normal Hb concentration (female: Hb > or =12.0 g/dl; male: > or =13.0 g/dl). RESULTS No significant difference in tumor oxygenation could be detected between mildly anemic patients and patients with a normal Hb level. However, the tumor oxygenation in the severely anemic group was significantly below that of each of the other two groups (p < 0.0001). There was no significant difference between the Hb groups in oxygenation of sternocleidomastoid muscles. In a multivariate analysis including Hb group, tumor volume, smoking habits, gender, T-stage, N-stage, and histologic grade a Hb level < 11 g/dl was found to be the strongest predictor for a poor tumor oxygenation. Smoking also had a marginal influence on median pO2. CONCLUSION Our data suggest that a low Hb concentration and cigarette smoking contribute to inadequate oxygenation of SCCHN and thus for increased radioresistance. Consequently, Hb correction and abstinence from smoking may significantly improve tumor oxygenation.


Neuro-oncology | 2011

Temozolomide in the treatment of high-grade gliomas in children: a report from the Children's Oncology Group

Kenneth J. Cohen; Ian F. Pollack; Tianni Zhou; Allen Buxton; Emiko J. Holmes; Peter C. Burger; Daniel J. Brat; Marc K. Rosenblum; Ronald L. Hamilton; Robert S. Lavey; Richard L. Heideman

To determine whether temozolomide is an active agent in the treatment of children with high-grade astrocytomas and whether survival is influenced by the expression of the O6-methylguanine-methyltransferase gene (MGMT) in these patients. In the Childrens Oncology Group study ACNS0126, 107 patients with a diagnosis of anaplastic astrocytoma (AA), glioblastoma multiforme (GBM), or gliosarcoma were enrolled. All patients underwent concomitant chemoradiotherapy with temozolomide, followed by adjuvant chemotherapy with temozolomide. The outcomes were compared with those of children treated in Childrens Cancer Group (CCG) study CCG-945. Formalin-fixed, paraffin-embedded tumor tissue was available in 71 cases for immunohistochemical analysis of MGMT expression. Ninety patients were deemed eligible, 31 with AA, 55 with GBM, and 4 with other eligible diagnoses. The 3-year event-free survival (EFS) and overall survival (OS) rates were 11 ± 3% and 22 ± 5%, respectively. There was no evidence that temozolomide given during radiation therapy and as adjuvant therapy resulted in improved EFS compared with that found in CCG-945 (p = 0.98). The 3-year EFS rate for AA was 13 ± 6% in ACNS0126 compared with 22 ± 5.5% in CCG-945 (p = 0.95). The 3-year EFS rate for GBM was 7 ± 4% in ACNS0126 compared with 15 ± 5% in CCG-945 (p = 0.77). The 2-year EFS rate was 17 ± 5% among patients without MGMT overexpression and 5 ± 4% among those with MGMT overexpression (p = 0.045). Temozolomide failed to improve outcome in children with high-grade astrocytomas. MGMT overexpression was adversely associated with survival.


Neuro-oncology | 2011

Temozolomide in the treatment of children with newly diagnosed diffuse intrinsic pontine gliomas: a report from the Children's Oncology Group

Kenneth J. Cohen; Richard L. Heideman; Tianni Zhou; Emiko J. Holmes; Robert S. Lavey; Eric Bouffet; Ian F. Pollack

An open-label phase II study (ACNS0126) testing the efficacy of chemoradiotherapy with temozolomide (TMZ) followed by adjuvant TMZ was conducted by the Childrens Oncology Group. During the period from July 6, 2004 through September 6, 2005, 63 children with newly diagnosed diffuse intrinsic pontine glioma (DIPG) were enrolled in the study. All patients received TMZ at a dosage of 90 mg/m(2)/day for 42 days to a dose of 59.4 Gy. Four weeks following irradiation, TMZ was given at a dosage of 200 mg/m(2)/day for 5 days every 28 days, for a total of 10 cycles. The primary objective of the statistical analysis was to determine whether the current treatment produced a 1-year event-free survival (EFS) rate higher than the historical baseline of 21.9% observed in CCG-9941. The mean 1-year EFS (± standard deviation) was 14% ± 4.5%, compared with 21.9% ± 5% for CCG-9941. The P value of the test of comparison of 1-year EFS, based on a 1-sided, 1-sample test of proportions, was .96. There was no evidence that temozolomide produced a 1-year EFS rate higher than 21.9%. The mean 1-year OS (± standard deviation) was 40% ± 6.5%, compared with 32% ± 6% for CCG-9941. The median time to death was 9.6 months. Chemoradiotherapy with TMZ followed by adjuvant TMZ is not more effective than previously reported regimens for the treatment of children with DIPG.


International Journal of Radiation Oncology Biology Physics | 1992

Erythropoietin increases hemoglobin in cancer patients during radiation therapy

Robert S. Lavey; W. Hilton Dempsey

PURPOSE The hemoglobin (Hgb) level of patients during radiation therapy is associated with both survival and local tumor control in several organ sites. This clinical trial tested whether administering recombinant human erythropoietin (r-HuEPO) to cancer patients would increase their Hgb level during the course of radiation therapy without adverse effects. METHODS AND MATERIALS The 40 participating patients had a Hgb value < 13.5 g/dL and a malignant tumor located above the diaphragm without evidence of distant metastasis for which they were scheduled to undergo a 5-8 week course of daily radiation therapy. All 40 patients were given oral ferrous sulfate throughout their radiation therapy course. Half the patients also received 150-300 mg/kg of r-HuEPO subcutaneously three times per week starting 0-10 days prior to the first dose of radiation. RESULTS The r-HuEPO and control groups did not differ significantly in patient age, gender, tumor type, initial hemoglobin, erythropoietin, or iron bioavailability. The Hgb level increased more than 6% during radiation therapy in all 20 of the r-HuEPO patients but in only 2/20 of the control patients (p < 0.001). The Hgb rose from a mean +/- standard deviation of 11.9 +/- 1.3 g/dL to > 14 g/dL during radiation therapy in 80% of the r-HuEPO group compared to in 5% of the control group (p < 0.001). The mean +/- s.d. change in Hgb concentration during radiation therapy was 27 +/- 15% (an average rise of 5% per week) in the r-HuEPO group and 0 +/- 6% in the control group (p < 0.001). r-HuEPO had no significant measurable effect on blood pressure, white blood cell, neutrophil or platelet count, or liver or renal function. The only reported adverse effect of r-HuEPO administration was an asymptomatic skin rash in one patient. CONCLUSION r-HuEPO with ferrous sulfate significantly increased the Hgb level in cancer patients without interfering with their course of radiation therapy, whereas ferrous sulfate alone did not. r-HuEPO appears to be a safe and effective means of increasing red cell mass during radiation therapy.


Cancer | 2012

AAML03P1, a pilot study of the safety of gemtuzumab ozogamicin in combination with chemotherapy for newly diagnosed childhood acute myeloid leukemia: a report from the Children's Oncology Group.

Todd Cooper; Robert B. Gerbing; Todd A. Alonzo; Craig A. Hurwitz; Susana C. Raimondi; Betsy Hirsch; Franklin O. Smith; Prasad Mathew; Robert J. Arceci; James H. Feusner; Robert Iannone; Robert S. Lavey; Soheil Meshinchi; Alan S. Gamis

The development of antigen‐targeted therapies may provide additional options to improve outcomes in children with acute myeloid leukemia (AML). The Childrens Oncology Group AAML03P1 trial sought to determine the safety of adding 2 doses of gemtuzumab ozogamicin, a humanized anti‐CD33 antibody‐targeted agent, to intensive chemotherapy during remission induction and postremission intensification for children with de novo AML.


International Journal of Radiation Oncology Biology Physics | 1992

Dose, time, and fraction size issues for late effects in head and neck cancers

Jeremy M. G. Taylor; William M. Mendenhall; Robert S. Lavey

This paper contains a statistical analysis of the dose-time factors influencing late complications in 784 patients with squamous cell carcinomas of the pharynx or larynx treated with external beam irradiation only at the University of Florida. The patients include 560 who received continuous course once-a-day therapy, 116 who received twice-a-day treatment, and 108 who received a once-a-day split course regimen. Both 2+ and 3+ complications were considered. Fifty-six patients developed either of these complications. The factors included in the analysis were site and size of the primary, total dose, fraction size, and treatment time. The linear-quadratic model was used to incorporate fraction size into the analysis. Proportional hazards analysis, which models the time to occurrence of the late complication, was used to quantify the joint influence of the above patient and fractionation variables on the incidence of late effects. The occurrence of the late effects was heterogeneous, with only a weak relationship to the patient and fractionation variables. The influence of the size of the primary was significant, with larger primaries associated with higher complication rates independent of fractionation variables. For oropharynx primary sites there was no significant effect of the fractionation variables. For larynx and hypopharynx, excluding T1-T2 true vocal cord, there was a significant effect of total dose and fraction size. The alpha/beta ratio was estimated to be 7.8 Gy (95% confidence interval, 3.0, infinity). There was no significant effect of overall treatment time. The estimated 2+ complication rate at 1 year from 68 Gy given in 2 Gy fractions in 50 days is 0.1% for T 1-2 vocal cord, 4.1% for T1-T2 supraglottic larynx, 3.8% for T3 supraglottic larynx and vocal cord, 14.9% for T4 supraglottic larynx, 6.7% for T1-T2 tonsil and soft palate, 7.6% for T3-T4 tonsil and soft palate, 7.0% for T1-T2 pyriform sinus and pharyngeal wall, and 13.0% for T3-T4 pyriform sinus and pharyngeal wall.


Cancer | 1990

Impact on second malignancy risk of the combined use of radiation and chemotherapy for lymphomas

Robert S. Lavey; Nancy L. Eby; Leonard R. Prosnitz

The risk of a second malignancy was determined for 999 patients given primary treatment using chemotherapy only, radiation therapy only, or both for Hodgkins Disease or a non‐Hodgkins lymphoma at Duke University Medical Center between 1970 and 1981. The incidence, 10‐year actuarial risk, and relative risk of developing an acute leukemia, solid tumor, or second lymphoma were determined by treatment modality and initial lymphoma type. Among the 313 Hodgkins disease patients, the acute leukemia actuarial risk was 2.0% after chemotherapy, 1.4% after radiation therapy, and 0.9% after combined treatment with chemotherapy and radiation therapy. Their relative risk for acute leukemia was 51.3 overall (95% confidence interval [CI] 13.8 to 131.8) and was elevated in each treatment group. Among the 686 non‐Hodgkins lymphoma patients, the acute leukemia actuarial risk was zero after radiation therapy, 4.6% after chemotherapy, and 4.5% after the combined treatment, again not significantly different between treatment groups. The leukemia relative risk was 10.6 (95% CI 3.4 to 24.8) in the chemotherapy and 11.9 (95% CI 3.2 to 30.6) in the combined treatment group. Among both the Hodgkins disease and non‐Hodgkins lymphoma populations, the combined treatment group had a lower actuarial risk for solid tumors than either the chemotherapy or radiation therapy group (P < 0.02). Solid tumor actuarial risk did not differ significantly between the chemotherapy and radiation therapy groups. Hodgkins disease patients had a solid tumor relative risk that was elevated significantly after radiation therapy (6.5; 95% CI 2.4 to 14.0) and to a lesser extent after chemotherapy (2.6; 95% CI 0.8 to 6.1) or combined treatment (1.7; 95% CI 0.2 to 6.0). Solid tumor relative risk among non‐Hodgkins lymphoma patients was 0.3 for the combined treatment, 0.8 for the chemotherapy, and 1.0 for the radiation therapy group. None of the Hodgkins disease patients developed a non‐Hodgkins lymphoma. This study found no significant difference in leukemia risk among lymphoma patients treated with chemotherapy and the combined treatment. It also found that the overall risk of a second malignancy is no higher after treatment with the combined therapy than with chemotherapy or radiation therapy alone.


Cancer | 2004

Antiangiogenic activity of genistein in pancreatic carcinoma cells is mediated by the inhibition of hypoxia-inducible factor-1 and the down-regulation of VEGF gene expression

Peter Büchler; Howard A. Reber; Markus W. Büchler; Helmut Friess; Robert S. Lavey; Oscar J. Hines

Previous reports indicate that Genistein, a naturally occurring isoflavonoid, exhibits strong antiangiogenic activity. The underlying mechanism of inhibition, however, remains unclear. Among the biologic effects of Genistein are the inhibition of tyrosine kinases and the inhibition of hypoxic activation of hypoxia‐inducible factor‐1 (HIF‐1), one of the main regulators of VEGF gene expression.


Journal of Clinical Oncology | 2012

Outcome After Surgery Alone or With Restricted Use of Chemotherapy for Patients With Low-Risk Neuroblastoma: Results of Children's Oncology Group Study P9641

Douglas Strother; Wendy B. London; Mary Lou Schmidt; Garrett M. Brodeur; Hiroyuki Shimada; Paul S. Thorner; Margaret H. Collins; Edward P. Tagge; Stanton Adkins; C. Patrick Reynolds; Kevin Murray; Robert S. Lavey; Katherine K. Matthay; Robert P. Castleberry; John M. Maris; Susan L. Cohn

PURPOSE The primary objective of Childrens Oncology Group study P9641 was to demonstrate that surgery alone would achieve 3-year overall survival (OS) ≥ 95% for patients with asymptomatic International Neuroblastoma Staging System stages 2a and 2b neuroblastoma (NBL). Secondary objectives focused on other low-risk patients with NBL and on those who required chemotherapy according to protocol-defined criteria. PATIENTS AND METHODS Patients underwent maximally safe resection of tumor. Chemotherapy was reserved for patients with, or at risk for, symptomatic disease, with less than 50% tumor resection at diagnosis, or with unresectable progressive disease after surgery alone. RESULTS For all 915 eligible patients, 5-year event-free survival (EFS) and OS were 89% ± 1% and 97% ± 1%, respectively. For patients with asymptomatic stage 2a or 2b disease, 5-year EFS and OS were 87% ± 2% and 96% ± 1%, respectively. Among patients with stage 2b disease, EFS and OS were significantly lower for those with unfavorable histology or diploid tumors, and OS was significantly lower for those ≥ 18 months old. For patients with stage 1 and 4s NBL, 5-year OS rates were 99% ± 1% and 91% ± 1%, respectively. Patients who required chemotherapy at diagnosis achieved 5-year OS of 98% ± 1%. Of all patients observed after surgery, 11.1% experienced recurrence or progression of disease. CONCLUSION Excellent survival rates can be achieved in asymptomatic low-risk patients with stages 2a and 2b NBL after surgery alone. Immediate use of chemotherapy may be restricted to a minority of patients with low-risk NBL. Patients with stage 2b disease who are older or have diploid or unfavorable histology tumors fare less well. Future studies will seek to refine risk classification.

Collaboration


Dive into the Robert S. Lavey's collaboration.

Top Co-Authors

Avatar

Arthur J. Olch

Children's Hospital Los Angeles

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Alan S. Gamis

Children's Mercy Hospital

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Judith G. Villablanca

University of Southern California

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Soheil Meshinchi

Fred Hutchinson Cancer Research Center

View shared research outputs
Top Co-Authors

Avatar

Susana C. Raimondi

St. Jude Children's Research Hospital

View shared research outputs
Top Co-Authors

Avatar

Todd A. Alonzo

University of Southern California

View shared research outputs
Researchain Logo
Decentralizing Knowledge