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Dive into the research topics where Keith J. Stelzer is active.

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Featured researches published by Keith J. Stelzer.


Journal of Clinical Oncology | 1995

Concurrent cisplatin/etoposide plus chest radiotherapy followed by surgery for stages IIIA (N2) and IIIB non-small-cell lung cancer: mature results of Southwest Oncology Group phase II study 8805.

Kathy S. Albain; Valerie W. Rusch; John Crowley; Thomas W. Rice; Andrew T. Turrisi; James K. Weick; Vassyl A. Lonchyna; Cary A. Presant; Robert J. McKenna; David R. Gandara; Helen Fosmire; Sarah A. Taylor; Keith J. Stelzer; Kristen R. Beasley; Robert B. Livingston

PURPOSEnTo assess the feasibility of concurrent chemotherapy and irradiation (chemoRT) followed by surgery in locally advanced non-small-cell lung cancer (NSCLC) in a cooperative group setting, and to estimate response, resection rates, relapse patterns, and survival for stage subsets IIIA(N2) versus IIIB.nnnPATIENTS AND METHODSnBiopsy proof of either positive N2 nodes (IIIAN2) or of N3 nodes or T4 primary lesions (IIIB) was required. Induction was two cycles of cisplatin and etoposide plus concurrent chest RT to 45 Gy. Resection was attempted if response or stable disease occurred. A chemoRT boost was given if either unresectable disease or positive margins or nodes was found.nnnRESULTSnThe median follow-up time for 126 eligible patients [75 stage IIIA(N2) and 51 IIIB] was 2.4 years. The objective response rate to induction was 59%, and 29% were stable. Resectability was 85% for the IIIA(N2) group eligible for surgery and 80% for the IIIB group. Reversible grade 4 toxicity occurred in 13% of patients. There were 13 treatment-related deaths (10%) and 19 others (15%) died of causes not related to toxicity or tumor. Of 65 relapses, 11% were only locoregional and 61% were only distant. There were 26 brain relapses, of which 19 were the sole site or cause of death. There was no survival difference (P = .81) between stage IIIA(N2) versus stage IIIB (median survivals, 13 and 17 months; 2-year survival rates, 37% and 39%; 3-year survival rates, 27% and 24%). The strongest predictor of long-term survival after thoracotomy was absence of tumor in the mediastinal nodes at surgery (median survivals, 30 v 10 months; 3-year survival rates, 44% v 18%; P = .0005).nnnCONCLUSIONnThis trimodality approach was feasible in this Southwest Oncology Group (SWOG) study, with an encouraging 26% 3-year survival rate. An Intergroup study is currently being conducted to determine whether surgery adds more to the risk or to the benefit of chemoRT.


The New England Journal of Medicine | 2016

Radiation plus Procarbazine, CCNU, and Vincristine in Low-Grade Glioma

Jan C. Buckner; Edward G. Shaw; Stephanie L. Pugh; Arnab Chakravarti; Mark R. Gilbert; Geoffrey R. Barger; Stephen W. Coons; Peter Ricci; Dennis E. Bullard; Paul D. Brown; Keith J. Stelzer; David Brachman; John H. Suh; Christopher J. Schultz; Jean Paul Bahary; Barbara Fisher; Harold Kim; Albert Murtha; Erica Hlavin Bell; Minhee Won; Minesh P. Mehta; Walter J. Curran

BACKGROUNDnGrade 2 gliomas occur most commonly in young adults and cause progressive neurologic deterioration and premature death. Early results of this trial showed that treatment with procarbazine, lomustine (also called CCNU), and vincristine after radiation therapy at the time of initial diagnosis resulted in longer progression-free survival, but not overall survival, than radiation therapy alone. We now report the long-term results.nnnMETHODSnWe included patients with grade 2 astrocytoma, oligoastrocytoma, or oligodendroglioma who were younger than 40 years of age and had undergone subtotal resection or biopsy or who were 40 years of age or older and had undergone biopsy or resection of any of the tumor. Patients were stratified according to age, histologic findings, Karnofsky performance-status score, and presence or absence of contrast enhancement on preoperative images. Patients were randomly assigned to radiation therapy alone or to radiation therapy followed by six cycles of combination chemotherapy.nnnRESULTSnA total of 251 eligible patients were enrolled from 1998 through 2002. The median follow-up was 11.9 years; 55% of the patients died. Patients who received radiation therapy plus chemotherapy had longer median overall survival than did those who received radiation therapy alone (13.3 vs. 7.8 years; hazard ratio for death, 0.59; P=0.003). The rate of progression-free survival at 10 years was 51% in the group that received radiation therapy plus chemotherapy versus 21% in the group that received radiation therapy alone; the corresponding rates of overall survival at 10 years were 60% and 40%. A Cox model identified receipt of radiation therapy plus chemotherapy and histologic findings of oligodendroglioma as favorable prognostic variables for both progression-free and overall survival.nnnCONCLUSIONSnIn a cohort of patients with grade 2 glioma who were younger than 40 years of age and had undergone subtotal tumor resection or who were 40 years of age or older, progression-free survival and overall survival were longer among those who received combination chemotherapy in addition to radiation therapy than among those who received radiation therapy alone. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT00003375.).


The Annals of Thoracic Surgery | 1994

Neoadjuvant therapy: A novel and effective treatment for stage IIIb non-small cell lung cancer

John Crowley; Valerie W. Rusch; Kathy S. Albain; Thomas W. Rice; Vassyl A. Lonchyna; Robert J. McKenna; Keith J. Stelzer; Robert B. Livingston

Neoadjuvant therapy has become an accepted treatment for stage IIIa, but not for stage IIIb, non-small cell lung cancer, which is usually considered incurable and treated nonsurgically. We determined the feasibility of neoadjuvant therapy in the setting of stage IIIb non-small cell lung cancer in a prospective multi-institutional trial. For patients to be eligible for entry into the study, they had to have pathologically documented T1-4 N2-3 disease. Treatment consisted of: (1) cisplatin (50 mg/m2) given on days 1, 8, 29, and 36 plus VP-16 (50 mg/m2) given on days 1 to 5 and 29 to 33, together with concurrent radiotherapy (4,500 cGy; 180 cGy per daily fraction); and (2) surgical resection performed 3 to 5 weeks after induction of medical therapy, if the response was stable, partial, or complete. Of the 126 total eligible patients entered into the study, 51 patients had stage IIIb tumors (24 with T4 tumors and 27 with N3 disease). This consisted of 34 men and 17 women with a median age of 57 years. Thirty-two (63%) patients (18 with T4 tumors and 14 with N3 disease) underwent resection of the primary tumor, with a 5.2% operative mortality. There was no difference in the operative time, blood loss, and length of hospital stay for the T4 versus the N3 patients. For all 51 patients, survival at 2 years was 39%. Sites of relapse in all patients were mainly distant, even though patients with N3 disease did not initially have involved N3 nodes resected.(ABSTRACT TRUNCATED AT 250 WORDS)


Neurosurgery | 1995

Radiation therapy for sarcoid of the thalamus/posterior third ventricle: case report.

Keith J. Stelzer; Charles R. Thomas; Mitchel S. Berger; Alexander M. Spence; Cheng Mei Shaw; Thomas W. Griffin

There are a limited number of previously reported cases involving the use of radiation therapy for sarcoid of the brain. The case of a 22-year-old man with a thalamic/posterior third ventricle sarcoid mass that grew despite steroid medication is presented. The patient was treated with external beam radiation to a total dose of 20 Gy, with 2-Gy fractions over 14 elapsed days. A complete radiographic response was achieved 4 months after radiation was completed. Radiographic follow-up through 8 months postradiation shows no evidence of disease recurrence. Fractionated radiation therapy in low-to-moderate doses appears to be efficacious in steroid-refractory sarcoid of the brain.


Journal of Neuro-oncology | 1997

Boron neutron capture enhanced fast neutron radiotherapy for malignant gliomas and other tumors

Thomas A. Buchholz; George E. Laramore; Keith J. Stelzer; Rudolf Risler; Peter Wootton; Thomas W. Griffin

Both fast neutron radiotherapy and boron neutron capturetherapy have been investigated as new radiation treatmenttechniques for patients with malignant gliomas. While eachof these techniques individually has shown the potentialfor pathological eradication of malignant glioma, to dateneither has evolved into an accepted, improved methodof treatment. We have recently begun a researchprogram investigating the feasibility of combining the benefitsof both types of therapy. As a fastneutron beam penetrates tissue some of the particlesare degraded to thermal energies. These can becaptured by 10B or other suitable isotopes resultingin a highly-localized release of additional energy duringa course of fast neutron radiotherapy. In thisarticle we will review the rationale for suchan approach, and review the underlying physics aswell as in vitro, in vivo, and earlyhuman studies testing its feasibility. If appropriate carrieragents can be found that preferentially-localize in tumorcells, this approach cna be applied to manydifferent tumor systems.


Acta Oncologica | 1994

Fast Neutron Radiotherapy: The University of Washington experience

Keith J. Stelzer; George E. Laramore; Thomas W. Griffin; Wui Jin Koh; Mary Austin-Seymour; Kenneth J. Russell; Thomas A. Buchholz

An overview of the University of Washington neutron radiotherapy facility is presented. The utility of the multi-leaf, programmable, variable collimator is emphasized. Due to success in the treatment of salivary gland tumors, such patients comprise an ever increasing portion of the patients being treated. A cooperative randomized clinical trial for the treatment of salivary gland tumors was undertaken comparing fast neutrons against photon/electron radiation. At ten years, there was a statistically significant improvement in local/regional control for the neutron group (56% vs 25%, p = 0.009), but there was no improvement in survival (15% vs 25%, p = n.s.). Distant metastases were the primary reason for the failure of improved local/regional control to impact survival in the neutron group. The University of Washington experience is summarized with special emphasis on the treatment of adenoid cystic carcinomas. Excellent local/regional control can be achieved with neutrons even for large tumors arising in the paranasal sinuses. We conclude that the potential morbidity of a surgical debulking procedure is not warranted in most clinical situations.


Computerized Medical Imaging and Graphics | 1998

Digital radiotherapy simulator

Pau S. Cho; Karen L. Lindsley; James G. Douglas; Keith J. Stelzer; Thomas W. Griffin

We describe a prototype digital radiotherapy simulator which consists of a conventional simulator gantry, digital spot imager, and image correction and reconstruction software. The ability of the digital spot imager to acquire a diagnostic quality image directly in digital format during simulation offers unique possibilities in clinical practice. Applications include prescription of multileaf collimator, on-line patient setup verification, remote consultation and treatment planning. In addition, we discuss the possibility of using the digital simulator as a volume-CT scanner capable of obtaining three-dimensional anatomical information in a single scan.


Neurosurgery | 1995

Radiation Therapy for Sarcoid of the ThalamussPosterior Third Ventricle

Keith J. Stelzer; Charles R. Thomas; Mitchel S. Berger; Alexander M. Spence; Cheng-Mei Shaw; Thomas W. Griffin

There are a limited number of previously reported cases involving the use of radiation therapy for sarcoid of the brain. The case of a 22-year-old man with a thalamic/posterior third ventricle sarcoid mass that grew despite steroid medication is presented. The patient was treated with external beam radiation to a total dose of 20 Gy, with 2-Gy fractions over 14 elapsed days. A complete radiographic response was achieved 4 months after radiation was completed. Radiographic follow-up through 8 months postradiation shows no evidence of disease recurrence. Fractionated radiation therapy in low-to-moderate doses appears to be efficacious in steroid-refractory sarcoid of the brain.


International Journal of Radiation Oncology Biology Physics | 1998

Concurrent Cisplatin, Prolonged Oral Etoposide, and Vincristine plus Chest and Brain Irradiation for Limited Small Cell Lung Cancer: A Phase II Study of the Southwest Oncology Group (SWOG-9229)

Charles R. Thomas; Dori J Giroux; Keith J. Stelzer; Johnny B Craig; Leslie Rodgers Laufman; Sarah A Taylor; John W Goodwin; John Crowley; Robert Livingston

PURPOSEnThe primary objectives of the study were to evaluate the efficacy and safety of prolonged oral (PO) etoposide as part of cisplatin-based chemotherapy plus concurrent chest/brain irradiation induction, followed by CAV consolidation, in the treatment of patients with limited-stage small cell lung cancer (SCLC-LD) within a cooperative group setting.nnnMETHODS AND MATERIALSnFifty-six eligible patients with SCLC-LD received three 28-day cycles of cisplatin 50 mg/m2 i.v. (days 1, 8; 29, 36; and 57, 64), PO etoposide 50 mg/m2 (days 1-14, 29-42, and 57-70), and vincristine 2 mg i.v. (days 1, 29, and 57). Thoracic irradiation (TRT) was administered at 1.8 Gy in 25 daily fractions to a total dose of 45 Gy via an AP:PA arrangement, to begin concomitantly with induction chemotherapy. Prophylactic cranial irradiation (PCI) was started on day 15 of induction therapy. Fifteen daily fractions of 2.0 Gy were administered to the entire brain to a total dose of 30 Gy to finish at approximately the same time as TRT. Two 21-day cycles of consolidation cyclophosphamide 750 mg/m2 i.v., doxorubicin 50 mg/m2 i.v., and vincristine 2 mg i.v. (all on days 1 and 22), were given beginning on day 106 or week 16, from the start of induction therapy.nnnRESULTSnAmong 56 eligible patients, 93% had SWOG performance status 0-1. All had adequate organ function and had not received prior therapy. The overall confirmed response rate was 46%, including 16% complete responders and 30% partial responders. After a minimum follow-up duration of 17 months, the Kaplan-Meier median progression-free (PFS) and overall survival (OS) were 10 and 15 months, respectively. Two-year survival is 28%. Only 28 of 56 patients (50%) completed chemotherapy per protocol, while 52 of 56 patients (93%) completed radiation per protocol. Eleven patients (20%) discontinued secondary to toxicity and two patients died from treatment. The major toxicity was hematologic. The two deaths were secondary to infection. Of the nonhematologic toxicities, there were 10 cases of pulmonary fibrosis (including one Grade 3) and six cases of pneumonitis (including one Grade 3).nnnCONCLUSIONnConcomitant chemoradiation with oral etoposide as part of a platinum-based chemotherapy and TRT induction regimen is toxic. The CR rate is not better than our prior best group-wide experience. The progression-free and overall survival are similar to published trials utilizing short-course i.v. etoposide. As in chemotherapy for extensive-stage SCLC, there is no apparent advantage to prolonged exposure to etoposide, and toxicity resulted in an inferior therapeutic index compared to programs with shortened exposure.


Pediatric Neurosurgery | 2001

Permanent Low-Activity 125I Seed Placement for the Treatment of Pediatric Brain Tumors: Preliminary Experience

Robert C. Rostomily; John Halligan; Russ Geyer; Keith J. Stelzer; Karen Lindsley; Mitchel S. Berger

Although external beam radiation therapy is effective in the treatment of many pediatric brain neoplasms its use in this patient population has been associated with the development of significant cognitive and endocrine dysfunction and is severely limited as an option in previously irradiated patients. Therefore, we have adopted a strategy for management of residual microscopic disease by implantation of low-activity 125I seeds in the tumor bed at the time of surgery. Six patients aged 2–14 years with recurrent tumors including two supratentorial primitive neuroectodermal tumors (n = 2), one medulloblastoma, one malignant ependymoma (n = 1), glioblastoma (n = 1) and one pleomorphic xanthoastrocytoma were implanted at the time of reoperation. A total of 11–126 seeds were implanted resulting in total doses of 16–21.8 Gy (after theoretical infinite time) at a depth of 5 mm from the implanted resection bed. Five patients had prior external beam radiation while the other patient (2 years old at initial diagnosis) progressed after surgery and chemotherapy. Two patients had lasting local tumor control. One patient is alive at 390 weeks of follow-up and another who died of distant failure at 366 weeks had no recurrence on MRI at 333 weeks’ follow-up. Only 2 patients had first local failures. These results suggest that the use of permanent low-activity 125I seeds as an adjunct to surgery can provide good local tumor control and is a suitable treatment option for pediatric patients.

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David Brachman

St. Joseph's Hospital and Medical Center

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Mark R. Gilbert

University of Texas MD Anderson Cancer Center

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