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Dive into the research topics where Robert Ivker is active.

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Featured researches published by Robert Ivker.


International Journal of Radiation Oncology Biology Physics | 2008

Phase II Trial of Combined High-Dose-Rate Brachytherapy and External Beam Radiotherapy for Adenocarcinoma of the Prostate: Preliminary Results of RTOG 0321

I-Chow Hsu; Kyounghwa Bae; Katsuto Shinohara; Jean Pouliot; James A. Purdy; Geoffrey S. Ibbott; Joycelyn Speight; E. Vigneault; Robert Ivker; Howard M. Sandler

PURPOSEnTo estimate the rate of late Grade 3 or greater genitourinary (GU) and gastrointestinal (GI) adverse events (AEs) after treatment with external beam radiotherapy and prostate high-dose-rate (HDR) brachytherapy.nnnMETHODS AND MATERIALSnEach participating institution submitted computed tomography-based HDR brachytherapy dosimetry data electronically for credentialing and for each study patient. Patients with locally confined Stage T1c-T3b prostate cancer were eligible for the present study. All patients were treated with 45 Gy in 25 fractions using external beam radiotherapy and one HDR implant delivering 19 Gy in two fractions. All AEs were graded according to the Common Terminology Criteria for Adverse Events, version 3.0. Late GU/GI AEs were defined as those occurring >9 months from the start of the protocol treatment, in patients with ≥18 months of potential follow-up.nnnRESULTSnA total of 129 patients from 14 institutions were enrolled in the present study. Of the 129 patients, 125 were eligible, and AE data were available for 112 patients at analysis. The pretreatment characteristics of the patients were as follows: Stage T1c-T2c, 91%; Stage T3a-T3b, 9%; prostate-specific antigen level ≤10 ng/mL, 70%; prostate-specific antigen level >10 but ≤20 ng/mL, 30%; and Gleason score 2-6, 10%; Gleason score 7, 72%; and Gleason score 8-10, 18%. At a median follow-up of 29.6 months, three acute and four late Grade 3 GU/GI AEs were reported. The estimated rate of late Grade 3-5 GU and GI AEs at 18 months was 2.56%.nnnCONCLUSIONnThis is the first prospective, multi-institutional trial of computed tomography-based HDR brachytherapy and external beam radiotherapy. The technique and doses used in the present study resulted in acceptable levels of AEs.


Journal of Palliative Medicine | 2008

Can physicians accurately predict survival time in patients with metastatic cancer? Analysis of RTOG 97-14

William F. Hartsell; Michelle DeSilvio; Deborah Watkins Bruner; Charles W. Scarantino; Robert Ivker; Mack Roach; John H. Suh; W. Demas; Benjamin Movsas; Ivy A. Petersen; Andre Konski

PURPOSEnTo determine if physician prediction of survival duration (PSD) is accurate for patients with metastatic breast or prostate cancer.nnnMETHODSnRadiation Therapy Oncology Group 9714 (RTOG 9714) was a randomized comparison of radiotherapy schedules for treatment of bone metastases. The treating physician assigned a baseline Karnofsky Performance Score (KPS) and predicted survival duration at study entry. Patients completed the Functional Assessment of Cancer Therapy (FACT). These three were compared to actual survival time.nnnRESULTSnEight hundred ninety-eight patients were eligible and analyzable. Actual median survival was 9.3 months. The median PSD was 12 months. PSD, KPS, and FACT were all moderately correlated with actual survival. Patients with higher KPS had a longer survival time (882 patients, Spearmans rho = 0.259, p < 0.0001). The median survival of the 618 expired patients is 6.5 months (PSD was 12 months). The PSD was within 1 month of actual survival in 61 (10%), with 177 (29%) patients surviving more than 1 month longer than predicted and 375 (61%) surviving more than 1 month less than predicted. A univariate analysis of actual overall survival was performed, dividing the PSD into 4 groups. For predicted survivals of 6 months or less, less than 6 to less than 12 months, 12 months, and more than 12 months, median actual survivals were 7.0, 7.2, 9.7. and 13.5 months (p < 0.0001).nnnCONCLUSIONSnKPS, FACT scores, and PSD all are correlated with actual survival. Physicians on this study were able to predict which patients would have longer survival times, although prediction of survival was optimistic compared to actual survival by an average of 3 months.


International Journal of Radiation Oncology Biology Physics | 2008

Functional interference clusters in cancer patients with bone metastases: a secondary analysis of RTOG 9714.

Edward Chow; Jennifer L. James; Andrea Barsevick; William F. Hartsell; Sarah J. Ratcliffe; Charles W. Scarantino; Robert Ivker; Mack Roach; John H. Suh; Ivy A. Petersen; Andre Konski; W. Demas; Deborah Watkins Bruner

PURPOSEnTo explore the relationships (clusters) among the functional interference items in the Brief Pain Inventory (BPI) in patients with bone metastases.nnnMETHODSnPatients enrolled in the Radiation Therapy Oncology Group (RTOG) 9714 bone metastases study were eligible. Patients were assessed at baseline and 4, 8, and 12 weeks after randomization for the palliative radiotherapy with the BPI, which consists of seven functional items: general activity, mood, walking ability, normal work, relations with others, sleep, and enjoyment of life. Principal component analysis with varimax rotation was used to determine the clusters between the functional items at baseline and the follow-up. Cronbachs alpha was used to determine the consistency and reliability of each cluster at baseline and follow-up.nnnRESULTSnThere were 448 male and 461 female patients, with a median age of 67 years. There were two functional interference clusters at baseline, which accounted for 71% of the total variance. The first cluster (physical interference) included normal work and walking ability, which accounted for 58% of the total variance. The second cluster (psychosocial interference) included relations with others and sleep, which accounted for 13% of the total variance. The Cronbachs alpha statistics were 0.83 and 0.80, respectively. The functional clusters changed at week 12 in responders but persisted through week 12 in nonresponders.nnnCONCLUSIONnPalliative radiotherapy is effective in reducing bone pain. Functional interference component clusters exist in patients treated for bone metastases. These clusters changed over time in this study, possibly attributable to treatment. Further research is needed to examine these effects.


American Journal of Clinical Oncology | 2016

Utility of the Ace Inhibitor Captopril in Mitigating Radiation-associated Pulmonary Toxicity in Lung Cancer: Results From Nrg Oncology Rtog 0123

William Small; Jennifer L. James; Timothy D. Moore; Dan J. Fintel; Stephen Lutz; Benjamin Movsas; Mohan Suntharalingam; Yolanda I. Garces; Robert Ivker; John E. Moulder; Stephanie L. Pugh; Lawrence Berk

Objectives: The primary objective of NRG Oncology Radiation Therapy Oncology Group 0123 was to test the ability of the angiotensin-converting enzyme inhibitor captopril to alter the incidence of pulmonary damage after radiation therapy for lung cancer; secondary objectives included analyzing pulmonary cytokine expression, quality of life, and the long-term effects of captopril. Materials and Methods: Eligible patients included stage II-IIIB non–small cell lung cancer, stage I central non–small cell lung cancer, or limited-stage small cell. Patients who met eligibility for randomization at the end of radiotherapy received either captopril or standard care for 1 year. The captopril was to be escalated to 50 mg three times a day. Primary endpoint was incidence of grade 2+ radiation-induced pulmonary toxicity in the first year. Results: Eighty-one patients were accrued between June 2003 and August 2007. Given the low accrual rate, the study was closed early. No significant safety issues were encountered. Eight patients were ineligible for registration or withdrew consent before randomization and 40 patients were not randomized postradiation. Major reasons for nonrandomization included patients’ refusal and physician preference. Of the 33 randomized patients, 20 were analyzable (13 observation, 7 captopril). The incidence of grade 2+ pulmonary toxicity attributable to radiation therapy was 23% (3/13) in the observation arm and 14% (1/7) in the captopril arm. Conclusions: Despite significant resources and multiple amendments, NRG Oncology Radiation Therapy Oncology Group 0123 was unable to test the hypothesis that captopril mitigates radiation-induced pulmonary toxicity. It did show the safety of such an approach and the use of newer angiotensin-converting enzyme inhibitors started during radiotherapy may solve the accrual problems.


Journal of the National Cancer Institute | 2005

Randomized trial of short- versus long-course radiotherapy for palliation of painful bone metastases

William F. Harstell; Charles Scott; Deborah Watkins Bruner; Charles W. Scarantino; Robert Ivker; Mack Roach; John H. Suh; W. Demas; Benjamin Movsas; Ivy A. Petersen; Andre Konski; Charles S. Cleeland; Nora A. Janjan; Michelle DeSilvio


International Journal of Radiation Oncology Biology Physics | 2003

Phase III randomized trial of 8 Gy in 1 fraction vs. 30 Gy in 10 fractions for palliation of painful bone metastases: preliminary results of RTOG 97-14

William F. Hartsell; Charles E. Scott; Deborah Watkins Bruner; Charles W. Scarantino; Robert Ivker; M. Roach; John H. Suh; W. Demas; Benjamin Movsas; Ivy A. Petersen; Andre Konski


World Journal of Oncology | 2011

Validation of a Predictive Model for Survival in Patients With Advanced Cancer: Secondary Analysis of RTOG 9714

Edward Chow; Jennifer L. James; William F. Hartsell; Charles W. Scarantino; Robert Ivker; Mack Roach; John H. Suh; W. Demas; Andre Konski; Deborah Watkins Bruner


Journal of pain management | 2010

Confirmatory factor analysis of brief pain inventory (BPI) functional interference clusters in patients with bone metastases.

Edward Chow; Jennifer L. James; Andrea Barsevick; William F. Hartsell; Sarah J. Ratcliffe; Charles W. Scarantino; Robert Ivker; John H. Suh; Ivy A. Petersen; Andre Konski; W. Demas; Deborah Watkins Bruner


International Journal of Radiation Oncology Biology Physics | 2009

A Phase II Randomized Trial with Captopril in Patients Who Have Received Radiation Therapy +/- Chemotherapy for Stage II–IIIB Non–small Cell Lung Cancer and Stage I Central Non–small Cell Lung Cancer, or Limited-stage Small–cell Lung Cancer: RTOG 0123

William Small; Jennifer L. James; T. Moore; Dan J. Fintel; Stephen Lutz; Benjamin Movsas; Mohan Suntharalingam; Y. Graces; Robert Ivker; Lawrence Berk


Fuel and Energy Abstracts | 2009

A Phase II Randomized Trial with Captopril in Patients Who Have Received Radiation Therapy +/- Chemo

William Small; Jennifer L. James; Thomas J. Moore; Dan J. Fintel; Sven Lutz; Benjamin Movsas; Mohan Suntharalingam; Y. Graces; Robert Ivker; Lawrence Berk

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Jennifer L. James

Radiation Therapy Oncology Group

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William F. Hartsell

Rush University Medical Center

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Mack Roach

University of California

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