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Featured researches published by Jonathan Knisely.


Journal of Clinical Oncology | 2012

Summary Report on the Graded Prognostic Assessment: An Accurate and Facile Diagnosis-Specific Tool to Estimate Survival for Patients With Brain Metastases

Paul W. Sperduto; Norbert Kased; David Roberge; Zhiyuan Xu; Ryan Shanley; Xianghua Luo; Penny K. Sneed; Samuel T. Chao; Robert J. Weil; John H. Suh; Amit Bhatt; Ashley W. Jensen; Paul D. Brown; Helen A. Shih; John P. Kirkpatrick; Laurie E. Gaspar; John B. Fiveash; Veronica L. Chiang; Jonathan Knisely; Christina Maria Sperduto; Nan Lin; Minesh P. Mehta

PURPOSE Our group has previously published the Graded Prognostic Assessment (GPA), a prognostic index for patients with brain metastases. Updates have been published with refinements to create diagnosis-specific Graded Prognostic Assessment indices. The purpose of this report is to present the updated diagnosis-specific GPA indices in a single, unified, user-friendly report to allow ease of access and use by treating physicians. METHODS A multi-institutional retrospective (1985 to 2007) database of 3,940 patients with newly diagnosed brain metastases underwent univariate and multivariate analyses of prognostic factors associated with outcomes by primary site and treatment. Significant prognostic factors were used to define the diagnosis-specific GPA prognostic indices. A GPA of 4.0 correlates with the best prognosis, whereas a GPA of 0.0 corresponds with the worst prognosis. RESULTS Significant prognostic factors varied by diagnosis. For lung cancer, prognostic factors were Karnofsky performance score, age, presence of extracranial metastases, and number of brain metastases, confirming the original Lung-GPA. For melanoma and renal cell cancer, prognostic factors were Karnofsky performance score and the number of brain metastases. For breast cancer, prognostic factors were tumor subtype, Karnofsky performance score, and age. For GI cancer, the only prognostic factor was the Karnofsky performance score. The median survival times by GPA score and diagnosis were determined. CONCLUSION Prognostic factors for patients with brain metastases vary by diagnosis, and for each diagnosis, a robust separation into different GPA scores was discerned, implying considerable heterogeneity in outcome, even within a single tumor type. In summary, these indices and related worksheet provide an accurate and facile diagnosis-specific tool to estimate survival, potentially select appropriate treatment, and stratify clinical trials for patients with brain metastases.


International Journal of Radiation Oncology Biology Physics | 2009

Diagnosis-specific prognostic factors, indexes, and treatment outcomes for patients with newly diagnosed brain metastases: a multi-institutional analysis of 4,259 patients.

Paul W. Sperduto; Samuel T. Chao; Penny K. Sneed; Xianghua Luo; John H. Suh; David Roberge; Amit Bhatt; Ashley W. Jensen; Paul D. Brown; Helen A. Shih; John P. Kirkpatrick; Amanda L. Schwer; Laurie E. Gaspar; John B. Fiveash; Veronica L. Chiang; Jonathan Knisely; Christina Maria Sperduto; Minesh P. Mehta

PURPOSE Controversy endures regarding the optimal treatment of patients with brain metastases (BMs). Debate persists, despite many randomized trials, perhaps because BM patients are a heterogeneous population. The purpose of the present study was to identify significant diagnosis-specific prognostic factors and indexes (Diagnosis-Specific Graded Prognostic Assessment [DS-GPA]). METHODS AND MATERIALS A retrospective database of 5,067 patients treated for BMs between 1985 and 2007 was generated from 11 institutions. After exclusion of the patients with recurrent BMs or incomplete data, 4,259 patients with newly diagnosed BMs remained eligible for analysis. Univariate and multivariate analyses of the prognostic factors and outcomes by primary site and treatment were performed. The significant prognostic factors were determined and used to define the DS-GPA prognostic indexes. The DS-GPA scores were calculated and correlated with the outcomes, stratified by diagnosis and treatment. RESULTS The significant prognostic factors varied by diagnosis. For non-small-cell lung cancer and small-cell lung cancer, the significant prognostic factors were Karnofsky performance status, age, presence of extracranial metastases, and number of BMs, confirming the original GPA for these diagnoses. For melanoma and renal cell cancer, the significant prognostic factors were Karnofsky performance status and the number of BMs. For breast and gastrointestinal cancer, the only significant prognostic factor was the Karnofsky performance status. Two new DS-GPA indexes were thus designed for breast/gastrointestinal cancer and melanoma/renal cell carcinoma. The median survival by GPA score, diagnosis, and treatment were determined. CONCLUSION The prognostic factors for BM patients varied by diagnosis. The original GPA was confirmed for non-small-cell lung cancer and small-cell lung cancer. New DS-GPA indexes were determined for other histologic types and correlated with the outcome, and statistical separation between the groups was confirmed. These data should be considered in the design of future randomized trials and in clinical decision-making.


Journal of Neurosurgery | 2012

Radiosurgery for melanoma brain metastases in the ipilimumab era and the possibility of longer survival

Jonathan Knisely; James B. Yu; Jaclyn C. Flanigan; Mario Sznol; Harriet M. Kluger; Veronica L. Chiang

OBJECT A prospectively collected cohort of 77 patients who underwent definitive radiosurgery between 2002 and 2010 for melanoma brain metastases was retrospectively reviewed to assess the impact of ipilimumab use and other clinical variables on survival. METHODS The authors conducted an institutional review board-approved chart review to assess patient age at the time of brain metastasis diagnosis, sex, primary disease location, initial radiosurgery date, number of metastases treated, performance status, systemic therapy and ipilimumab history, whole-brain radiation therapy (WBRT) use, follow-up duration, and survival at the last follow-up. The Diagnosis-Specific Graded Prognostic Assessment (DSGPA) score was calculated for each patient based on performance status and the number of brain metastases treated. RESULTS Thirty-five percent of the patients received ipilimumab. The median survival in this group was 21.3 months, as compared with 4.9 months in patients who did not receive ipilimumab. The 2-year survival rate was 47.2% in the ipilimumab group compared with 19.7% in the nonipilimumab group. The DS-GPA score was the most significant predictor of overall survival, and ipilimumab therapy was also independently associated with an improvement in the hazard for death (p = 0.03). CONCLUSIONS The survival of patients with melanoma brain metastases managed with ipilimumab and definitive radiosurgery can exceed the commonly anticipated 4-6 months. Using ipilimumab in a supportive treatment paradigm of radiosurgery for brain oligometastases was associated with an increased median survival from 4.9 to 21.3 months, with a 2-year survival rate of 19.7% versus 47.2%. This association between ipilimumab and prolonged survival remains significant even after adjustment for performance status without an increased need for salvage WBRT.


International Journal of Radiation Oncology Biology Physics | 2012

Effect of Tumor Subtype on Survival and the Graded Prognostic Assessment for Patients With Breast Cancer and Brain Metastases

Paul W. Sperduto; Norbert Kased; David Roberge; Zhiyuan Xu; Ryan Shanley; Xianghua Luo; Penny K. Sneed; Samuel T. Chao; Robert J. Weil; John H. Suh; Amit Bhatt; Ashley W. Jensen; Paul D. Brown; Helen A. Shih; John P. Kirkpatrick; Laurie E. Gaspar; John B. Fiveash; Veronica L. Chiang; Jonathan Knisely; Christina Maria Sperduto; Nan Lin; Minesh P. Mehta

PURPOSE The diagnosis-specific Graded Prognostic Assessment (GPA) was published to clarify prognosis for patients with brain metastases. This study refines the existing Breast-GPA by analyzing a larger cohort and tumor subtype. METHODS AND MATERIALS A multi-institutional retrospective database of 400 breast cancer patients treated for newly diagnosed brain metastases was generated. Prognostic factors significant for survival were analyzed by multivariate Cox regression and recursive partitioning analysis (RPA). Factors were weighted by the magnitude of their regression coefficients to define the GPA index. RESULTS Significant prognostic factors by multivariate Cox regression and RPA were Karnofsky performance status (KPS), HER2, ER/PR status, and the interaction between ER/PR and HER2. RPA showed age was significant for patients with KPS 60 to 80. The median survival time (MST) overall was 13.8 months, and for GPA scores of 0 to 1.0, 1.5 to 2.0, 2.5 to 3.0, and 3.5 to 4.0 were 3.4 (n = 23), 7.7 (n = 104), 15.1 (n = 140), and 25.3 (n = 133) months, respectively (p < 0.0001). Among HER2-negative patients, being ER/PR positive improved MST from 6.4 to 9.7 months, whereas in HER2-positive patients, being ER/PR positive improved MST from 17.9 to 20.7 months. The log-rank statistic (predictive power) was 110 for the Breast-GPA vs. 55 for tumor subtype. CONCLUSIONS The Breast-GPA documents wide variation in prognosis and shows clear separation between subgroups of patients with breast cancer and brain metastases. This tool will aid clinical decision making and stratification in clinical trials. These data confirm the effect of tumor subtype on survival and show the Breast-GPA offers significantly more predictive power than the tumor subtype alone.


Journal of Clinical Oncology | 2005

Phase II Trial of Radiosurgery for One to Three Newly Diagnosed Brain Metastases From Renal Cell Carcinoma, Melanoma, and Sarcoma: An Eastern Cooperative Oncology Group Study (E 6397)

Rafael Manon; Anne O'Neill; Jonathan Knisely; Maria Werner-Wasik; Hillard M. Lazarus; Henry N. Wagner; Mark R. Gilbert; Minesh P. Mehta

PURPOSE Long-term brain metastases survivors are at risk for neurologic morbidity after whole-brain radiotherapy (WBRT). Retrospective radiosurgery (RS) reports found no survival difference when compared with WBRT. Before RS alone was evaluated with delayed WBRT in a phase III trial, the feasibility of RS alone was tested prospectively. PATIENTS AND METHODS Patients with renal cell carcinoma, melanoma, or sarcoma; one to three brain metastases; and performance status of 0 to 2 were enrolled. Exclusion criteria were leptomeningeal disease; metastases in medulla, pons, or midbrain; or liver metastases. On the basis of tumor size, patients received 24, 18, or 15 Gy RS. At recurrence, management was discretionary. The primary end point was 3- and 6-month intracranial progression. RESULTS Between July 1998 and August 2003, 36 patients were accrued; 31 were eligible. Median follow-up was 32.7 months and the median survival was 8.3 months (95% CI, 7.4 to 12.2). Three- and 6-month intracranial failure with RS alone was 25.8% and 48.3%. Failure within and outside the RS volume, when in-field and distant intracranial failures were scored independently, was 19.3% and 16.2% (3 months) and 32.2% and 32.2% (6 months), respectively. Approximately 38% of patients experienced death attributable to neurologic cause. There were three grade 3 toxicities related to RS. CONCLUSION Intracranial failure rates without WBRT were 25.8% and 48.3% at 3 and 6 months, respectively. Delaying WBRT may be appropriate for some subgroups of patients with radioresistant tumors, but routine avoidance of WBRT should be approached judiciously.


Radiotherapy and Oncology | 1999

Polarographic measurements of oxygen tension in human glioma and surrounding peritumoural brain tissue

David R. Collingridge; Joseph M. Piepmeier; Sara Rockwell; Jonathan Knisely

This study quantifies the spatial distribution of pO2 in glioma and in the surrounding brain tissue. Both glioma and peritumoural brain contain regions at oxygen tensions less than 2.5 mmHg. Modalities targeting hypoxia to improve the efficacy of therapy may have an important role in the management of this disease.


Journal of Clinical Oncology | 2000

Phase II Evaluation of Preoperative Chemoradiation and Postoperative Adjuvant Chemotherapy for Squamous Cell and Adenocarcinoma of the Esophagus

Elisabeth I. Heath; Barbara A. Burtness; Richard F. Heitmiller; Ronald Salem; Lawrence Kleinberg; Jonathan Knisely; Stephen C. Yang; Mark A. Talamini; Howard S. Kaufman; Marcia I. Canto; Mark Topazian; Tsung Teh Wu; Koleoso Olukayode; Arlene A. Forastiere

PURPOSE This phase II trial evaluated continuous-infusion cisplatin and fluorouracil (5-FU) with radiotherapy followed by esophagectomy. The objectives of this trial were to determine the complete pathologic response rate, survival rate, toxicity, pattern of failure, and feasibility of administering adjuvant chemotherapy in patients with resectable cancer of the esophagus treated with preoperative chemoradiation. PATIENTS AND METHODS Patients were staged using computed tomography, endoscopic ultrasound, and laparoscopy. The preoperative treatment plan consisted of continuous intravenous infusion of cisplatin and 5-FU and a total dose of 44 Gy of radiation. Esophagogastrectomy was planned for approximately 4 weeks after the completion of chemoradiotherapy. Paclitaxel and cisplatin were administered as postoperative adjuvant therapy. RESULTS Forty-two patients were enrolled onto the trial. Of the 39 patients who proceeded to surgery, 29 responded to preoperative treatment: 11 achieved pathologic complete response (CR) and 18 achieved a lower posttreatment stage. Five patients had no change in stage, whereas eight had progressive disease (four with distant metastases and four with increases in the T and N stages). At a median follow-up of 30.2 months, the median survival time has not been reached and the 2-year survival rate is 62%. The median survival of pathologic complete responders has not been reached, whereas the 2-year survival rate of this group is 91% compared with 51% in patients with complete tumor resection with residual tumor (P =.03). CONCLUSION An excellent survival rate, comparable to that of our prior preoperative trial, was achieved with lower doses of preoperative cisplatin and 5-FU concurrent with radiotherapy.


International Journal of Radiation Oncology Biology Physics | 2008

A Phase III Study of Conventional Radiation Therapy Plus Thalidomide Versus Conventional Radiation Therapy for Multiple Brain Metastases (RTOG 0118)

Jonathan Knisely; Brian Berkey; Arnab Chakravarti; Al W.K. Yung; Walter J. Curran; H. Ian Robins; Benjamin Movsas; David Brachman; R. Henderson; Minesh P. Mehta

PURPOSE To compare whole-brain radiation therapy (WBRT) with WBRT combined with thalidomide for patients with brain metastases not amenable to resection or radiosurgery. PATIENTS AND METHODS Patients with Zubrod performance status 0-1, MRI-documented multiple (>3), large (>4 cm), or midbrain brain metastases arising from a histopathologically confirmed extracranial primary tumor, and an anticipated survival of >8 weeks were randomized to receive WBRT to a dose of 37.5 Gy in 15 fractions with or without thalidomide during and after WBRT. Prerandomization stratification used Radiation Therapy Oncology Group (RTOG) Recursive Partitioning Analysis (RPA) Class and whether post-WBRT chemotherapy was planned. Endpoints included overall survival, progression-free survival, time to neurocognitive progression, the cause of death, toxicities, and quality of life. A protocol-planned interim analysis documented that the trial had an extremely low probability of ever showing a significant difference favoring the thalidomide arm given the results at the time of the analysis, and it was therefore closed on the basis of predefined statistical guidelines. RESULTS Enrolled in the study were 332 patients. Of 183 accrued patients, 93 were randomized to receive WBRT alone and 90 to WBRT and thalidomide. Median survival was 3.9 months for both arms. No novel toxicities were seen, but thalidomide was not well tolerated in this population. Forty-eight percent of patients discontinued thalidomide because of side effects. CONCLUSION Thalidomide provided no survival benefit for patients with multiple, large, or midbrain metastases when combined with WBRT; nearly half the patients discontinued thalidomide due to side effects.


Cancer | 2007

Prognostic factors for survival after stereotactic radiosurgery vary with the number of cerebral metastases

Michael L. DiLuna; Joseph T. King; Jonathan Knisely; Veronica L. Chiang

Little is understood about the factors that influence survival in patients who undergo gamma‐knife stereotactic radiosurgery (SRS) for brain metastases.


Neuroimaging Clinics of North America | 2002

Importance of hypoxia in the biology and treatment of brain tumors

Jonathan Knisely; Sara Rockwell

The resistance of gliomas to treatment with radiation and antineoplastic drugs may result in part from the effects of the extensive, severe hypoxia that is present in these tumors. It is clear that brain tumors contain extensive regions in which the tumor cells are subjected to unphysiological levels of hypoxia. Hypoxic cells are resistant to radiation. Hypoxia and the perfusion deficits and metabolic changes that accompany hypoxia in vivo also produce resistance to many commonly used anticancer drugs. The resistance of cells that are hypoxic at the time of therapy may influence the efficacy of the treatment of these tumors with radiation, chemotherapy, and combined modality regimens. Moreover, it is becoming increasingly evident from laboratory studies that exposure of cells to adverse microenvironments produces transient changes in gene expression, induces mutations, and selects for cells with altered genotypes, thus driving the evolution of the cell population toward increasing malignancy and increasingly aggressive phenotypes. Hypoxia may therefore be involved in the evolution of cells in low-grade malignancies to the resistant, aggressive phenotype characteristic of glioblastomas. During the past 50 years, many attempts have been made to circumvent the therapeutic resistance induced by hypoxia, by improving tumor oxygenation, by using oxygen-mimetic radiosensitizers, by adjuvant therapy with drugs that are preferentially toxic to hypoxic cells, by using hyperthermia, or by devising radiation sources and regimens that are less affected by hypoxia. Past clinical trials have provided tantalizing suggestions that the outcome of therapy can be improved by many of these approaches, but none has yet produced a significant, reproducible improvement in the therapeutic ratio, which would be needed for any of these approaches to become the standard therapy for these diseases. Several ongoing clinical trials are addressing other, hopefully better regimens; it will be interesting to see the results of these studies.

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Minesh P. Mehta

University of Wisconsin-Madison

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