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Featured researches published by Sasan Karimi.


International Journal of Radiation Oncology Biology Physics | 2009

Safety and Efficacy of Bevacizumab With Hypofractionated Stereotactic Irradiation for Recurrent Malignant Gliomas

Philip H. Gutin; Fabio M. Iwamoto; Kathryn Beal; Nimish Mohile; Sasan Karimi; Bob L. Hou; Stella Lymberis; Yoshiya Yamada; Jenghwa Chang; Lauren E. Abrey

PURPOSE Preclinical studies suggest that inhibition of vascular endothelial growth factor (VEGF) improves glioma response to radiotherapy. Bevacizumab, a monoclonal antibody against VEGF, has shown promise in recurrent gliomas, but the safety and efficacy of concurrent bevacizumab with brain irradiation has not been extensively studied. The objectives of this study were to determine the safety and activity of this combination in malignant gliomas. METHODS AND MATERIALS After prior treatment with standard radiation therapy patients with recurrent glioblastoma (GBM) and anaplastic gliomas (AG) received bevacizumab (10 mg/kg intravenous) every 2 weeks of 28-day cycles until tumor progression. Patients also received 30 Gy of hypofractionated stereotactic radiotherapy (HFSRT) in five fractions after the first cycle of bevacizumab. RESULTS Twenty-five patients (20 GBM, 5 AG; median age 56 years; median Karnofsky Performance Status 90) received a median of seven cycles of bevacizumab. One patient did not undergo HFSRT because overlap with prior radiotherapy would exceed the safe dose allowed to the optic chiasm. Three patients discontinued treatment because of Grade 3 central nervous system intratumoral hemorrhage, wound dehiscence, and bowel perforation. Other nonhematologic and hematologic toxicities were transient. No radiation necrosis was seen in these previously irradiated patients. For the GBM cohort, overall response rate was 50%, 6-month progression-free survival was 65%; median overall survival was 12.5 months, and 1-year survival was 54%. DISCUSSION Bevacizumab with HFSRT is safe and well tolerated. Radiographic responses, duration of disease control, and survival suggest that this regimen is active in recurrent malignant glioma.


Journal of Clinical Oncology | 2013

Rituximab, Methotrexate, Procarbazine, and Vincristine Followed by Consolidation Reduced-Dose Whole-Brain Radiotherapy and Cytarabine in Newly Diagnosed Primary CNS Lymphoma: Final Results and Long-Term Outcome

Patrick G. Morris; Denise D. Correa; Joachim Yahalom; Jeffrey Raizer; David Schiff; Barbara Grant; Sean Grimm; Rose Lai; Anne S. Reiner; K. S. Panageas; Sasan Karimi; Richard Curry; Gaurav D. Shah; Lauren E. Abrey; Lisa M. DeAngelis; Antonio Omuro

PURPOSE A multicenter phase II study was conducted to assess the efficacy of rituximab, methotrexate, procarbazine, and vincristine (R-MPV) followed by consolidation reduced-dose whole-brain radiotherapy (rdWBRT) and cytarabine in primary CNS lymphoma. PATIENTS AND METHODS Patients received induction chemotherapy with R-MPV (five to seven cycles); those achieving a complete response (CR) received rdWBRT (23.4 Gy), and otherwise, standard WBRT was offered (45 Gy). Consolidation cytarabine was given after the radiotherapy. The primary end point was 2-year progression-free survival (PFS) in patients receiving rdWBRT. Exploratory end points included prospective neuropsychological evaluation, analysis of magnetic resonance imaging (MRI) white matter changes using the Fazekas scale, and evaluation of the apparent diffusion coefficient (ADC) as a prognostic factor. RESULTS Fifty-two patients were enrolled, with median age of 60 years (range, 30 to 79 years) and median Karnofsky performance score of 70 (range, 50 to 100). Thirty-one patients (60%) achieved a CR after R-MPV and received rdWBRT. The 2-year PFS for this group was 77%; median PFS was 7.7 years. Median overall survival (OS) was not reached (median follow-up for survivors, 5.9 years); 3-year OS was 87%. The overall (N = 52) median PFS was 3.3 years, and median OS was 6.6 years. Cognitive assessment showed improvement in executive function (P < .01) and verbal memory (P < .05) after chemotherapy, and follow-up scores remained relatively stable across the various domains (n = 12). All examined MRIs (n = 28) displayed a Fazekas score of ≤ 3, and no patient developed scores of 4 to 5; differences in ADC values did not predict response (P = .15), PFS (P = .27), or OS (P = .33). CONCLUSION R-MPV combined with consolidation rdWBRT and cytarabine is associated with high response rates, long-term disease control, and minimal neurotoxicity.


Journal of Clinical Oncology | 2009

Randomized Phase II Trial of Chemoradiotherapy Followed by Either Dose-Dense or Metronomic Temozolomide for Newly Diagnosed Glioblastoma

Jennifer Clarke; Fabio M. Iwamoto; Joohee Sul; Katherine S. Panageas; Andrew B. Lassman; Lisa M. DeAngelis; Adília Hormigo; Craig Nolan; Igor T. Gavrilovic; Sasan Karimi; Lauren E. Abrey

PURPOSE Alternative dosing schedules of temozolomide may improve survival in patients with newly diagnosed glioblastoma (GBM) by increasing the therapeutic index, overcoming common mechanisms of temozolomide resistance, or both. The goal of this randomized phase II study was to evaluate two different temozolomide regimens in the adjuvant treatment of newly diagnosed GBM. PATIENTS AND METHODS Adult patients with newly diagnosed GBM were randomly assigned to receive standard radiotherapy with concurrent daily temozolomide followed by six adjuvant cycles of either dose-dense (150 mg/m(2) days 1 to 7 and 15 to 21) or metronomic (50 mg/m(2) continuous daily) temozolomide. Maintenance doses of 13-cis-retinoic acid were then administered until tumor progression. The primary end point was overall survival (OS) at 1 year. Tumor tissue was assayed to determine O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation status. RESULTS Eighty-five eligible patients were enrolled; 42 were randomly assigned to dose-dense and 43 to metronomic temozolomide. The 1-year survival rate was 80% for the dose-dense arm and 69% for the metronomic arm; median OS was 17.1 months (95% CI, 14.0 to 28.1 months) and 15.1 months (95% CI, 12.3 to 18.9 months), respectively. The most common toxicities were myelosuppression (leukopenia, neutropenia, and thrombocytopenia) and elevated liver enzymes. Pseudoprogression was observed in 37% of assessable patients and may have had an impact on estimates of progression-free survival (6.6 months in the dose-dense arm and 5.0 months in the metronomic arm). CONCLUSION Both dose-dense and metronomic temozolomide regimens were well tolerated with modest toxicity. The dose-dense regimen appears promising, with 1-year survival of 80%.


Neuro-oncology | 2015

Phase II trial of sunitinib for recurrent and progressive atypical and anaplastic meningioma

Thomas Kaley; Patrick Y. Wen; David Schiff; Keith L. Ligon; Sam Haidar; Sasan Karimi; Andrew B. Lassman; Craig Nolan; Lisa M. DeAngelis; Igor T. Gavrilovic; Andrew D. Norden; Jan Drappatz; Eudocia Q. Lee; Benjamin Purow; Scott R. Plotkin; Tracy T. Batchelor; Lauren E. Abrey; Antonio Omuro

BACKGROUND No proven effective medical therapy for surgery and radiation-refractory meningiomas exists. Sunitinib malate (SU011248) is a small-molecule tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor, abundant in meningiomas. METHODS This was a prospective, multicenter, investigator-initiated single-arm phase II trial. The primary cohort enrolled patients with surgery and radiation-refractory recurrent World Health Organization (WHO) grades II-III meningioma. An exploratory cohort enrolled patients with WHO grade I meningioma, hemangiopericytoma, or hemangioblastoma. Sunitinib was administered at 50 mg/d for days 1-28 of every 42-day cycle. The primary endpoint was the rate of 6-month progression-free survival (PFS6), with secondary endpoints of radiographic response rate, safety, PFS, and overall survival. Exploratory objectives include analysis of tumoral molecular markers and MR perfusion imaging. RESULTS Thirty-six patients with high-grade meningioma (30 atypical and 6 anaplastic) were enrolled. Patients were heavily pretreated (median number of 5 recurrences, range 2-10). PFS6 rate was 42%, meeting the primary endpoint. Median PFS was 5.2 months (95% CI: 2.8-8.3 mo), and median overall survival was 24.6 months (95% CI: 16.5-38.4 mo). Thirteen patients enrolled in the exploratory cohort. Overall toxicity included 1 grade 5 intratumoral hemorrhage, 2 grade 3 and 1 grade 4 CNS/intratumoral hemorrhages, 1 grade 3 and 1 grade 4 thrombotic microangiopathy, and 1 grade 3 gastrointestinal perforation. Expression of VEGFR2 predicted PFS of a median of 1.4 months in VEGFR2-negative patients versus 6.4 months in VEGFR2-positive patients (P = .005). CONCLUSION Sunitinib is active in recurrent atypical/malignant meningioma patients. A randomized trial should be performed.


International Journal of Radiation Oncology Biology Physics | 2012

Dynamic Contrast-Enhanced Magnetic Resonance Imaging as a Predictor of Outcome in Head-and-Neck Squamous Cell Carcinoma Patients With Nodal Metastases

Amita Shukla-Dave; Nancy Y. Lee; Jacobus F.A. Jansen; Howard T. Thaler; Hilda E. Stambuk; Matthew G. Fury; Snehal G. Patel; Andre L. Moreira; Eric J. Sherman; Sasan Karimi; Ya Wang; Dennis H. Kraus; Jatin P. Shah; David G. Pfister; Jason A. Koutcher

PURPOSE Dynamic contrast-enhanced MRI (DCE-MRI) can provide information regarding tumor perfusion and permeability and has shown prognostic value in certain tumors types. The goal of this study was to assess the prognostic value of pretreatment DCE-MRI in head and neck squamous cell carcinoma (HNSCC) patients with nodal disease undergoing chemoradiation therapy or surgery. METHODS AND MATERIALS Seventy-four patients with histologically proven squamous cell carcinoma and neck nodal metastases were eligible for the study. Pretreatment DCE-MRI was performed on a 1.5T MRI. Clinical follow-up was a minimum of 12 months. DCE-MRI data were analyzed using the Tofts model. DCE-MRI parameters were related to treatment outcome (progression-free survival [PFS] and overall survival [OS]). Patients were grouped as no evidence of disease (NED), alive with disease (AWD), dead with disease (DOD), or dead of other causes (DOC). Prognostic significance was assessed using the log-rank test for single variables and Cox proportional hazards regression for combinations of variables. RESULTS At last clinical follow-up, for Stage III, all 12 patients were NED. For Stage IV, 43 patients were NED, 4 were AWD, 11 were DOD, and 4 were DOC. K(trans) is volume transfer constant. In a stepwise Cox regression, skewness of K(trans) (volume transfer constant) was the strongest predictor for Stage IV patients (PFS and OS: p <0.001). CONCLUSION Our study shows that skewness of K(trans) was the strongest predictor of PFS and OS in Stage IV HNSCC patients with nodal disease. This study suggests an important role for pretreatment DCE-MRI parameter K(trans) as a predictor of outcome in these patients.


American Journal of Roentgenology | 2008

Craniofacial and Intracranial Manifestations of Langerhans Cell Histiocytosis: Report of Findings in 100 Patients

Nicholas D'Ambrosio; Stephanie Soohoo; Craig Warshall; Alan Johnson; Sasan Karimi

OBJECTIVE The purpose of this study was to review the craniofacial and intracranial clinical and radiologic manifestations of patients diagnosed with Langerhans cell histiocytosis (LCH). This report will compare the frequency of the various manifestations found in our series with those reported in the medical literature. CONCLUSION In LCH, involvement of the calvaria, skull base, maxillofacial bones, and hypothalamic-pituitary axis is fairly common. The precise location of these lesions contributes to the variety of clinical manifestations of LCH, which includes scalp and/or facial swelling, seizures, hearing loss, recurrent otitis media, gingival bleeding, proptosis, diabetes insipidus, and cranial nerve palsies.


American Journal of Neuroradiology | 2011

Isolated diffusion restriction precedes the development of enhancing tumor in a subset of patients with glioblastoma.

Ajay Gupta; Robert J. Young; Sasan Karimi; S. Sood; Zhigang Zhang; Q. Mo; Philip H. Gutin; Andrei I. Holodny; A.B. Lassman

We know that tumor contrast enhancement is preceded by development of increased perfusion and abnormal MR spectroscopy findings. Here, the authors determined that restricted diffusion also occurs before contrast enhancement in some glioblastomas. Visibly restricted apparent diffusion coefficient was found in 32% of patients undergoing treatment and 85% of those with nonenhancing low-ADC lesions went on to develop contrast enhancement at the site of restricted diffusion, implying tumor progression regardless of type of therapy. Conclusion: In a subset of patients with glioblastoma, development of a new focus of restricted diffusion during treatment may precede the development of new enhancing tumor. BACKGROUND AND PURPOSE: Most response criteria for patients with glioblastoma rely on increases in the contrast enhancing abnormality to determine tumor progression. Our aim was to determine retrospectively in patients with glioblastoma whether diffusion restriction can predict the development of new enhancing mass lesions. MATERIALS AND METHODS: We reviewed the brain MR imaging scans (including DWI and ADC maps) of 208 patients with glioblastoma. Patients with restricted diffusion in or adjacent to the tumor were identified, with further analysis only performed on those patients with low-ADC lesions without enhancement. These patients were followed to determine if new concordant enhancement developed at the site of the low-ADC lesion. A Wilcoxon signed rank test, competing risk analysis, and Kaplan-Meier curves were used to compare the mean drop in ADC values, assess enhancement-free survival, and determine overall survival, respectively. RESULTS: In 67 of the 208 patients (32.2%), visibly detectable restricted diffusion was seen during treatment. The study cohort was formed by the 27 patients with low-ADC lesions and no corresponding enhancement. Twenty-three (85.2%) patients developed gadolinium-enhancing tumor at the site of restricted diffusion a median of 3.0 months later (95% CI, 2.6–4.1 months). The mean decrease in ADC was 22.9% from baseline (P < .001). The 3-month enhancement-free survival probability was 0.481 (95% CI, 0.288–0.675). The 12-month overall survival probability was 0.521 (95% CI, 0.345–0.788). Restricted diffusion predicted enhancement regardless of antiangiogenic therapy with bevacizumab. CONCLUSIONS: In a subset of patients with glioblastoma, development of a new focus of restricted diffusion during treatment may precede the development of new enhancing tumor.


Journal of Magnetic Resonance Imaging | 2012

Skeletal muscle BOLD MRI: from underlying physiological concepts to its usefulness in clinical conditions.

Bjoern Jacobi; Georg Bongartz; Sasan Partovi; Anja Carina Schulte; Markus Aschwanden; Alan B. Lumsden; Mark G. Davies; Matthias Loebe; Georg P. Noon; Sasan Karimi; John K. Lyo; Daniel Staub; Rolf W. Huegli; Deniz Bilecen

Blood oxygenation‐level dependent (BOLD) MRI has gained particular attention in functional brain imaging studies, where it can be used to localize areas of brain activation with high temporal resolution. To a higher degree than in the brain, skeletal muscles show extensive but transient alterations of blood flow between resting and activation state. Thus, there has been interest in the application of the BOLD effect in studying the physiology of skeletal muscles (healthy and diseased) and its possible application to clinical practice. This review outlines the potential of skeletal muscle BOLD MRI as a diagnostic tool for the evaluation of physiological and pathological alterations in the peripheral limb perfusion, such as in peripheral arterial occlusive disease. Moreover, current knowledge is summarized regarding the complex mechanisms eliciting BOLD effect in skeletal muscle. We describe technical fundaments of the procedure that should be taken into account when performing skeletal muscle BOLD MRI, including the most often applied paradigms to provoke BOLD signal changes and key parameters of the resulting time courses. Possible confounding effects in muscle BOLD imaging studies, like age, muscle fiber type, training state, and drug effects are also reviewed in detail. J. Magn. Reson. Imaging 2012;35:1253–1265.


Clinical Cancer Research | 2014

Phase II Study of Bevacizumab, Temozolomide and Hypofractionated Stereotactic Radiotherapy for Newly Diagnosed Glioblastoma

Antonio Omuro; Kathryn Beal; Philip H. Gutin; Sasan Karimi; Denise D. Correa; Thomas Kaley; Lisa M. DeAngelis; Timothy A. Chan; Igor T. Gavrilovic; Craig Nolan; Adília Hormigo; Andrew B. Lassman; Ingo K. Mellinghoff; Christian Grommes; Anne S. Reiner; Katherine S. Panageas; Raymond E. Baser; Viviane Tabar; Elena Pentsova; Juan Sánchez; Renata Barradas-Panchal; Jianan Zhang; Geraldine Faivre; Cameron Brennan; Lauren E. Abrey; Jason T. Huse

Purpose: Bevacizumab is associated with decreased vascular permeability that allows for more aggressive radiotherapy schedules. We conducted a phase II trial in newly diagnosed glioblastoma utilizing a novel hypofractionated stereotactic radiotherapy (HFSRT) schedule combined with temozolomide and bevacizumab. Experimental Design: Patients with tumor volume ≤60 cc were treated with HFSRT (6 × 6 Gy to contrast enhancement and 6 × 4 Gy to FLAIR hyperintensity with dose painting) combined with concomitant/adjuvant temozolomide and bevacizumab at standard doses. Primary endpoint was 1-year overall survival (OS): promising = 70%; nonpromising = 50%; α = 0.1; β = 0.1. Results: Forty patients were enrolled (median age: 55 years; methylated MGMT promoter: 23%; unmethylated: 70%). The 1-year OS was 93% [95% confidence interval (CI), 84–100] and median OS was 19 months. The median PFS was 10 months, with no pseudo-progression observed. The objective response rate (ORR) was 57%. Analysis of The Cancer Genome Atlas glioblastoma transcriptional subclasses (Nanostring assay) suggested patients with a proneural phenotype (26%) fared worse (ORR = 14%, vs. 77% for other subclasses; P = 0.009). Dynamic susceptibility-contrast perfusion MRI showed marked decreases in relative cerebral blood volume over time (P < 0.0001) but had no prognostic value, whereas higher baseline apparent diffusion coefficient (ADC) ratios and persistent hypermetabolism at the 6-month FDG-PET predicted poor OS (P = 0.05 and 0.0001, respectively). Quality-of-life (FACT-BR-4) and neuropsychological test scores were stable over time, although some domains displayed transient decreases following HFSRT. Conclusions: This aggressive radiotherapy schedule was safe and more convenient for patients, achieving an OS that is comparable with historical controls. Analysis of advanced neuroimaging parameters suggests ADC and FDG-PET as potentially useful biomarkers, whereas tissue correlatives uncovered the poor prognosis associated with the proneural signature in non–IDH-1–mutated glioblastoma. Clin Cancer Res; 20(19); 5023–31. ©2014 AACR.


Neuro-oncology | 2011

Serum YKL-40 is a marker of prognosis and disease status in high-grade gliomas

Fabio M. Iwamoto; Andreas F. Hottinger; Sasan Karimi; Elyn Riedel; Jocelynn Dantis; Maryam Jahdi; Katherine S. Panageas; Andrew B. Lassman; Lauren E. Abrey; Martin Fleisher; Lisa M. DeAngelis; Eric C. Holland; Adília Hormigo

The objective of this study was to evaluate whether longitudinal levels of serum YKL-40 correlate with disease status or survival in adults with gliomas. Patients with histologically confirmed gliomas were eligible for this longitudinal study. Serum samples were collected prospectively and concurrently with MRI scans at multiple time points during the course of the disease. YKL-40 levels determined by ELISA were correlated with radiographic disease status and survival. We performed a multivariate survival analysis including well-known prognostic factors such as age, performance status, and extent of surgical resection. Three hundred and forty-three patients with gliomas (41 low-grade, 105 anaplastic, and 197 glioblastoma) were accrued. Two-year survival from registration was 29% for glioblastomas, 62% for anaplastic gliomas, and 83% for low-grade gliomas. A total of 1740 serum samples were collected, and 95.6% of samples had matching MRI scans. Serum YKL-40 level was significantly lower in patients with no radiographic disease compared with patients with radiographic disease in both the anaplastic glioma (P= .0008) and the glioblastoma (P= .0006) cohorts. Serum levels of YKL-40 in patients with low-grade gliomas were not associated with radiographic disease status. Increases in YKL-40 were independently associated with worse survival in anaplastic gliomas (hazard ratio [HR] = 1.4, P= .01) and glioblastomas (HR = 1.4, P< .0001). Longitudinal increases in serum YKL-40 are associated with increased risk of death in patients with glioblastomas and anaplastic gliomas. YKL-40 is also a putative indicator of disease status in these patients.

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John K. Lyo

Memorial Sloan Kettering Cancer Center

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Andrei I. Holodny

Memorial Sloan Kettering Cancer Center

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Lauren E. Abrey

Memorial Sloan Kettering Cancer Center

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Lisa M. DeAngelis

Memorial Sloan Kettering Cancer Center

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Kyung K. Peck

Memorial Sloan Kettering Cancer Center

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Robert J. Young

Memorial Sloan Kettering Cancer Center

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Eric Lis

Memorial Sloan Kettering Cancer Center

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Yoshiya Yamada

Memorial Sloan Kettering Cancer Center

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Andrew B. Lassman

Columbia University Medical Center

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Sasan Partovi

Houston Methodist Hospital

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