Samir Narayan
University of California, Davis
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Lancet Oncology | 2015
Jeff Bradley; Rebecca Paulus; Ritsuko Komaki; Gregory A. Masters; George R. Blumenschein; Steven E. Schild; Jeff Bogart; Chen Hu; Kenneth M. Forster; Anthony M. Magliocco; Vivek Kavadi; Yolanda I. Garces; Samir Narayan; Puneeth Iyengar; Cliff G. Robinson; Raymond B. Wynn; Christopher Koprowski; Joanne Meng; Jonathan J. Beitler; Rakesh Gaur; Walter J. Curran; Hak Choy
BACKGROUND We aimed to compare overall survival after standard-dose versus high-dose conformal radiotherapy with concurrent chemotherapy and the addition of cetuximab to concurrent chemoradiation for patients with inoperable stage III non-small-cell lung cancer. METHODS In this open-label randomised, two-by-two factorial phase 3 study in 185 institutions in the USA and Canada, we enrolled patients (aged ≥ 18 years) with unresectable stage III non-small-cell lung cancer, a Zubrod performance status of 0-1, adequate pulmonary function, and no evidence of supraclavicular or contralateral hilar adenopathy. We randomly assigned (1:1:1:1) patients to receive either 60 Gy (standard dose), 74 Gy (high dose), 60 Gy plus cetuximab, or 74 Gy plus cetuximab. All patients also received concurrent chemotherapy with 45 mg/m(2) paclitaxel and carboplatin once a week (AUC 2); 2 weeks after chemoradiation, two cycles of consolidation chemotherapy separated by 3 weeks were given consisting of paclitaxel (200 mg/m(2)) and carboplatin (AUC 6). Randomisation was done with permuted block randomisation methods, stratified by radiotherapy technique, Zubrod performance status, use of PET during staging, and histology; treatment group assignments were not masked. Radiation dose was prescribed to the planning target volume and was given in 2 Gy daily fractions with either intensity-modulated radiation therapy or three-dimensional conformal radiation therapy. The use of four-dimensional CT and image-guided radiation therapy were encouraged but not necessary. For patients assigned to receive cetuximab, 400 mg/m(2) cetuximab was given on day 1 followed by weekly doses of 250 mg/m(2), and was continued through consolidation therapy. The primary endpoint was overall survival. All analyses were done by modified intention-to-treat. The study is registered with ClinicalTrials.gov, number NCT00533949. FINDINGS Between Nov 27, 2007, and Nov 22, 2011, 166 patients were randomly assigned to receive standard-dose chemoradiotherapy, 121 to high-dose chemoradiotherapy, 147 to standard-dose chemoradiotherapy and cetuximab, and 110 to high-dose chemoradiotherapy and cetuximab. Median follow-up for the radiotherapy comparison was 22.9 months (IQR 27.5-33.3). Median overall survival was 28.7 months (95% CI 24.1-36.9) for patients who received standard-dose radiotherapy and 20.3 months (17.7-25.0) for those who received high-dose radiotherapy (hazard ratio [HR] 1.38, 95% CI 1.09-1.76; p=0.004). Median follow-up for the cetuximab comparison was 21.3 months (IQR 23.5-29.8). Median overall survival in patients who received cetuximab was 25.0 months (95% CI 20.2-30.5) compared with 24.0 months (19.8-28.6) in those who did not (HR 1.07, 95% CI 0.84-1.35; p=0.29). Both the radiation-dose and cetuximab results crossed protocol-specified futility boundaries. We recorded no statistical differences in grade 3 or worse toxic effects between radiotherapy groups. By contrast, the use of cetuximab was associated with a higher rate of grade 3 or worse toxic effects (205 [86%] of 237 vs 160 [70%] of 228 patients; p<0.0001). There were more treatment-related deaths in the high-dose chemoradiotherapy and cetuximab groups (radiotherapy comparison: eight vs three patients; cetuximab comparison: ten vs five patients). There were no differences in severe pulmonary events between treatment groups. Severe oesophagitis was more common in patients who received high-dose chemoradiotherapy than in those who received standard-dose treatment (43 [21%] of 207 patients vs 16 [7%] of 217 patients; p<0.0001). INTERPRETATION 74 Gy radiation given in 2 Gy fractions with concurrent chemotherapy was not better than 60 Gy plus concurrent chemotherapy for patients with stage III non-small-cell lung cancer, and might be potentially harmful. Addition of cetuximab to concurrent chemoradiation and consolidation treatment provided no benefit in overall survival for these patients. FUNDING National Cancer Institute and Bristol-Myers Squibb.
BMC Cancer | 2004
William H. Hall; Samir Narayan; Ashesh B. Jani; Srinivasan Vijayakumar
BackgroundUncertainty regarding comorbid illness, and ability to tolerate aggressive therapy has led to minimal enrollment of elderly cancer patients into clinical trials and often substandard treatment. Increasingly, comorbid illness scales have proven useful in identifying subgroups of elderly patients who are more likely to tolerate and benefit from aggressive therapy. Unfortunately, the use of such scales has yet to be widely integrated into either clinical practice or clinical trials research.MethodsThis article reviews evidence for the validity of the Charlson Comorbidity Index (CCI) in oncology and provides a Microsoft Excel (MS Excel) Macro for the rapid and accurate calculation of CCI score. The interaction of comorbidity and malignant disease and the validation of the Charlson Index in oncology are discussed.ResultsThe CCI score is based on one year mortality data from internal medicine patients admitted to an inpatient setting and is the most widely used comorbidity index in oncology. An MS Excel Macro file was constructed for calculating the CCI score using Microsoft Visual Basic. The Macro is provided for download and dissemination.The CCI has been widely used and validated throughout the oncology literature and has demonstrated utility for most major cancers. The MS Excel CCI Macro provides a rapid method for calculating CCI score with or without age adjustments. The calculator removes difficulty in score calculation as a limitation for integration of the CCI into clinical research. The simple nature of the MS Excel CCI Macro and the CCI itself makes it ideal for integration into emerging electronic medical records systems.ConclusionsThe increasing elderly population and concurrent increase in oncologic disease has made understanding the interaction between age and comorbid illness on life expectancy increasingly important. The MS Excel CCI Macro provides a means of increasing the use of the CCI scale in clinical research with the ultimate goal of improving determination of optimal treatments for elderly cancer patients.
Prostate Cancer and Prostatic Diseases | 2005
William H. Hall; Ashesh B. Jani; Janice Ryu; Samir Narayan; Srinivasan Vijayakumar
The management of localized prostate cancer is based on stage, grade, PSA, and subjective assessment of comorbidity and life expectancy. Over the last 15 y, stage migration and the improved use of Gleason sum, PSA and TNM staging have led to many treatment options for patients with newly diagnosed localized prostate cancer. At the same time, advances in treatment techniques have helped decrease the long-term complications of surgery and radiotherapy. However, the importance of age and comorbidity, in survival outcomes and treatment decision-making has been largely overlooked. Currently, stage, grade, and PSA are the only quantifiable variables consistently used in research and treatment decision-making. Comorbidity and life expectancy have remained largely subjective variables. Increasing longevity and a rapidly aging population have made age and comorbidity increasingly important factors in clinical research and treatment decision-making. This article reviews the importance of age and comorbidity on treatment decisions and survival outcomes in prostate cancer, as well as their use as objectively quantifiable variables. Examples from the general oncology literature are given. The overview also examines validated comorbidity indices and advocates the use of the Charlson Comorbidity Index (CCI) in research outcomes and treatment decision-making in prostate cancer. Several clinical vignettes are provided to demonstrate the potential clinical utility of the CCI as applied to prostate cancer.
International Journal of Radiation Oncology Biology Physics | 2002
Samir Narayan; Wayne T. Cornblath; Howard M. Sandler; Victor M. Elner; James A. Hayman
PURPOSE We assessed visual outcomes, local control, and toxicity associated with three-dimensional conformal radiation therapy (3D-CRT) for primary optic nerve sheath meningiomas (ONSM). METHODS Twenty-three patients diagnosed with ONSM were evaluated at the University of Michigan between 1986 and 2001. Fourteen patients were treated with 3D-CRT. Detailed pre- and postradiation treatment ophthalmologic examinations and MRIs were performed on all patients. Clinically significant visual acuity change was defined as a >or=three line change on the Snellen chart. Mean deviation change of >or=three decibels was defined as a clinically significant visual field change. Radiographic progression was defined as any increase in size on MRI. Acute and late toxicity was scored according to RTOG criteria. RESULTS Median follow-up was 51.3 months. Five patients had a clinically significant improvement in visual acuity. Seven had stable acuity, and only 2 worsened. Nine patients had clinically significant visual field improvement. One patient developed early radiation retinopathy, 1 experienced orbital pain, 1 developed dry eye, and 2 developed iritis. No patient has required additional treatment, and none have demonstrated radiographic progression. CONCLUSION 3D-CRT is effective in controlling tumor growth while improving or preserving vision in most patients with optic nerve sheath meningiomas.
International Journal of Radiation Oncology Biology Physics | 2008
William H. Hall; Michael Guiou; Nancy Y. Lee; Arthur B. Dublin; Samir Narayan; Srinivasan Vijayakumar; James A. Purdy; Allen M. Chen
PURPOSE Although Radiation Therapy Oncology Group protocols have proposed a limiting dose to the brachial plexus for patients undergoing intensity-modulated radiotherapy for head-and-neck cancer, essentially no recommendations exist for the delineation of this structure for treatment planning. METHODS AND MATERIALS Using anatomic texts, radiologic data, and magnetic resonance imaging, a standardized method for delineating the brachial plexus on 3-mm axial computed tomography images was devised. A neuroradiologist assisted with identification of the brachial plexus and adjacent structures. This organ at risk was then contoured on 10 consecutive patients undergoing intensity-modulated radiotherapy for head-and-neck cancer. Dose-volume histogram curves were generated by applying the proposed brachial plexus contour to the initial treatment plan. RESULTS The total dose to the planning target volume ranged from 60 to 70 Gy (median, 70). The mean brachial plexus volume was 33 +/- 4 cm(3) (range, 25.1-39.4). The mean irradiated volumes of the brachial plexus were 50 Gy (17 +/- 3 cm(3)), 60 Gy (6 +/- 3 cm(3)), 66 Gy (2 +/- 1 cm(3)), 70 Gy (0 +/- 1 cm(3)). The maximal dose to the brachial plexus was 69.9 Gy (range, 62.3-76.9) and was >/=60 Gy, >/=66 Gy, and >/=70 Gy in 100%, 70%, and 30% of patients, respectively. CONCLUSIONS This technique provides a precise and accurate method for delineating the brachial plexus organ at risk on treatment planning computed tomography scans. Our dosimetric analysis suggest that for patients undergoing intensity-modulated radiotherapy for head-and-neck cancer, brachial plexus routinely receives doses in excess of historic and Radiation Therapy Oncology Group limits.
Journal of Clinical Oncology | 2017
Stephen G. Chun; Chen Hu; Hak Choy; R. Komaki; Robert D. Timmerman; Steven E. Schild; Jeffrey A. Bogart; Michael C. Dobelbower; Walter R. Bosch; James M. Galvin; Vivek Kavadi; Samir Narayan; Puneeth Iyengar; C.G. Robinson; Raymond B. Wynn; Adam Raben; M. Augspurger; Robert M. MacRae; Rebecca Paulus; Jeffrey D. Bradley
Purpose Although intensity-modulated radiation therapy (IMRT) is increasingly used to treat locally advanced non-small-cell lung cancer (NSCLC), IMRT and three-dimensional conformal external beam radiation therapy (3D-CRT) have not been compared prospectively. This study compares 3D-CRT and IMRT outcomes for locally advanced NSCLC in a large prospective clinical trial. Patients and Methods A secondary analysis was performed to compare IMRT with 3D-CRT in NRG Oncology clinical trial RTOG 0617, in which patients received concurrent chemotherapy of carboplatin and paclitaxel with or without cetuximab, and 60- versus 74-Gy radiation doses. Comparisons included 2-year overall survival (OS), progression-free survival, local failure, distant metastasis, and selected Common Terminology Criteria for Adverse Events (version 3) ≥ grade 3 toxicities. Results The median follow-up was 21.3 months. Of 482 patients, 53% were treated with 3D-CRT and 47% with IMRT. The IMRT group had larger planning treatment volumes (median, 427 v 486 mL; P = .005); a larger planning treatment volume/volume of lung ratio (median, 0.13 v 0.15; P = .013); and more stage IIIB disease (30.3% v 38.6%, P = .056). Two-year OS, progression-free survival, local failure, and distant metastasis-free survival were not different between IMRT and 3D-CRT. IMRT was associated with less ≥ grade 3 pneumonitis (7.9% v 3.5%, P = .039) and a reduced risk in adjusted analyses (odds ratio, 0.41; 95% CI, 0.171 to 0.986; P = .046). IMRT also produced lower heart doses ( P < .05), and the volume of heart receiving 40 Gy (V40) was significantly associated with OS on adjusted analysis ( P < .05). The lung V5 was not associated with any ≥ grade 3 toxicity, whereas the lung V20 was associated with increased ≥ grade 3 pneumonitis risk on multivariable analysis ( P = .026). Conclusion IMRT was associated with lower rates of severe pneumonitis and cardiac doses in NRG Oncology clinical trial RTOG 0617, which supports routine use of IMRT for locally advanced NSCLC.
JAMA Oncology | 2016
Benjamin Movsas; Chen Hu; Jeff A. Sloan; Jeffrey D. Bradley; Ritsuko Komaki; Gregory A. Masters; Vivek Kavadi; Samir Narayan; Jeff M. Michalski; Douglas W. Johnson; Christopher Koprowski; Walter J. Curran; Yolanda I. Garces; Rakesh Gaur; Raymond B. Wynn; John M. Schallenkamp; D. Gelblum; Robert M. MacRae; Rebecca Paulus; Hak Choy
IMPORTANCE A recent randomized radiation dose-escalation trial in unresectable stage III non-small-cell lung cancer (NSCLC) (Radiation Therapy Oncology Group [RTOG] 0617) showed a lower survival rate in the high-dose radiation therapy (RT) arm (74 Gy) than in the low-dose arm (60 Gy) with concurrent chemotherapy. OBJECTIVE The primary QOL hypothesis predicted a clinically meaningful decline in quality of life (QOL) via the Functional Assessment of Cancer Therapy (FACT)-Lung Cancer Subscale (LCS) in the high-dose RT arm at 3 months. DESIGN, SETTING, AND PATIENTS The RTOG 0617 trial was a randomized phase 3 study (conducted from November 2007 to November 2011) in stage III NSCLC using a 2 × 2 factorial design and stratified by histology, positron emission tomography staging, performance status, and irradiation technique (3-dimensional conformal RT [3D-CRT] vs intensity-modulated RT [IMRT]). A total of 185 institutions in the United States and Canada took part. Of 424 eligible patients with stage III NSCLC randomized, 360 (85%) consented to QOL evaluation, of whom 313 (88%) completed baseline QOL assessments. INTERVENTION Treatment with 74-Gy vs 60-Gy RT with concurrent and consolidation carboplatin/paclitaxel with or without cetuximab. MAIN OUTCOMES AND MEASURES The QOL data were collected prospectively via FACT Trial Outcome Index (FACT-TOI), calculated as the sum of the following measures: Physical Well Being (PWB), Functional Well Being (FWB), and the LCS. Data are presented at baseline and 3 and 12 months via minimal clinically meaningful changes of 2 points or more for PWB, FWB, and LCS or 5 points or more for TOI. RESULTS Of the 313 patients who completed baseline QOL assessments, 219 patients (70%) completed the 3-month QOL assessments, and 137 of the living patients (57%) completed the 12-month assessment. Patient demographics and baseline QOL scores were comparable between the 74-Gy and 60-Gy arms. Significantly more patients in the 74-Gy arm than in the 60-Gy arm had clinically meaningful decline in FACT-LCS at 3 months (45% vs 30%; P = .02). At 12 months, fewer patients who received IMRT (vs 3D-CRT) had clinically meaningful decline in FACT-LCS (21% vs 46%; P = .003). Baseline FACT-TOI was associated with overall survival in multivariate analysis. CONCLUSIONS AND RELEVANCE Despite few differences in clinician-reported toxic effects between treatment arms, QOL analysis demonstrated a clinically meaningful decline in QOL in the 74-Gy arm at 3 months, confirming the primary QOL hypothesis. Baseline QOL was an independent prognostic factor for survival. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00533949.
Clinical Cancer Research | 2005
David R. Gandara; Samir Narayan; Primo N. Lara; Zelanna Goldberg; Angela M. Davies; Derrick Lau; Philip C. Mack; Paul H. Gumerlock; Srinivasan Vijayakumar
Novel therapeutic agents (NTA) directed against a wide array of newly described molecular targets are now entering clinical investigation, many in the treatment of non–small cell lung cancer (NSCLC). The great majority of these clinical trials have been directed toward patients with advanced stage (metastatic) disease. More recently, study of NTAs has turned toward earlier-stage disease. Locally advanced, or stage III, NSCLC represents a large and heterogeneous group of patients and several clinically distinct substages. During the last 15 years, randomized clinical trials have shown improved survival with sequential chemoradiation compared with radiation alone and, more recently, the superiority of concurrent versus sequential chemoradiation. As NTAs have increasingly shown clinical activity against NSCLC, questions of how to incorporate them into clinical trials in stage III disease, whether they should be given together with radiotherapy, substituting for chemotherapy, or whether they should be added to current chemoradiation strategies, all remain as issues. Here, we describe conceptual issues, preclinical rationale, and ongoing or planned clinical trials incorporating NTAs into current treatment paradigms for unresectable stage III NSCLC.
International Journal of Radiation Oncology Biology Physics | 2008
Samir Narayan; Joerg Lehmann; Matthew A. Coleman; Andrew T. Vaughan; C Yang; Danny Enepekides; G. Farwell; James A. Purdy; Grace Laredo; Kerry Nolan; Francesca S. Pearson; Srinivasan Vijayakumar
PURPOSE We conducted a clinical study to correlate oral cavity dose with clinical mucositis, perform in vivo dosimetry, and determine the feasibility of obtaining buccal mucosal cell samples in patients undergoing head-and-neck radiation therapy. The main objective is to establish a quantitative dose response for clinical oral mucositis. METHODS AND MATERIALS Twelve patients undergoing radiation therapy for head-and-neck cancer were prospectively studied. Four points were chosen in separate quadrants of the oral cavity. Calculated dose distributions were generated by using AcQPlan and Eclipse treatment planning systems. MOSFET dosimeters were used to measure dose at each sampled point. Each patient underwent buccal sampling for future RNA analysis before and after the first radiation treatment at the four selected points. Clinical and functional mucositis were assessed weekly according to National Cancer Institute Common Toxicity Criteria, Version 3. RESULTS Maximum and average doses for sampled sites ranged from 7.4-62.3 and 3.0-54.3 Gy, respectively. A cumulative point dose of 39.1 Gy resulted in mucositis for 3 weeks or longer. Mild severity (Grade </= 1) and short duration (</=1 week) of mucositis were found at cumulative point doses less than 32 Gy. Polymerase chain reaction consistently was able to detect basal levels of two known radiation responsive genes. CONCLUSIONS In our sample, cumulative doses to the oral cavity of less than 32 Gy were associated with minimal acute mucositis. A dose greater than 39 Gy was associated with longer duration of mucositis. Our technique for sampling buccal mucosa yielded sufficient cells for RNA analysis using polymerase chain reaction.
Journal of the National Cancer Institute | 2016
Bree R. Eaton; Stephanie L. Pugh; Jeffrey D. Bradley; Greg Masters; Vivek Kavadi; Samir Narayan; Lucien A. Nedzi; Cliff G. Robinson; Raymond B. Wynn; Christopher Koprowski; Douglas W. Johnson; Joanne Meng; Walter J. Curran
BACKGROUND The purpose of this analysis is to evaluate the effect of institutional accrual volume on clinical outcomes among patients receiving chemoradiation for locally advanced non-small cell lung cancer (LA-NSCLC) on a phase III trial. METHODS Patients with LA-NSCLC were randomly assigned to 60 Gy or 74 Gy radiotherapy (RT) with concurrent carboplatin/paclitaxel +/- cetuximab on NRG Oncology RTOG 0617. Participating institutions were categorized as low-volume centers (LVCs) or high-volume centers (HVCs) according to the number of patients accrued (≤3 vs > 3). All statistical tests were two-sided. RESULTS Range of accrual for LVCs (n = 195) vs HVCs (n = 300) was 1 to 3 vs 4 to 18 patients. Baseline characteristics were similar between the two cohorts. Treatment at a HVC was associated with statistically significantly longer overall survival (OS) and progression-free survival (PFS) compared with treatment at a LVC (median OS = 26.2 vs 19.8 months; HR = 0.70, 95% CI = 0.56 to 0.88, P = .002; median PFS: 11.4 vs 9.7 months, HR = 0.80, 95% CI = 0.65-0.99, P = .04). Patients treated at HVCs were more often treated with intensity-modulated RT (54.0% vs 39.5%, P = .002), had a lower esophageal dose (mean = 26.1 vs 28.0 Gy, P = .03), and had a lower heart dose (median = V5 Gy 38.2% vs 54.1%, P = .006; V50 Gy 3.6% vs 7.3%, P < .001). Grade 5 adverse events (AEs) (5.3% vs 9.2%, P = .09) and RT termination because of AEs (1.3% vs 4.1%, P = .07) were less common among patients treated at HVCs. HVC remained independently associated with longer OS (P = .03) when accounting for other factors. CONCLUSION Treatment at institutions with higher clinical trial accrual volume is associated with longer OS among patients with LA-NSCLC participating in a phase III trial.