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At least 1,495 records · Page 83
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

3-Dimensional Magnetic Resonance Spectroscopic Imaging at 3 Tesla for Early Response Assessment of Glioblastoma Patients During External Beam Radiation Therapy

Purpose: To evaluate the utility of 3-dimensional magnetic resonance (3D-MR) proton spectroscopic imaging for treatment planning and its implications for early response assessment in glioblastoma multiforme. Methods and Materials: Eighteen patients with newly diagnosed, histologically confirmed glioblastoma had 3D-MR proton spectroscopic imaging (MRSI) along with T2 and T1 gadolinium-enhanced MR images at simulation and at boost treatment planning after 17 to 20 fractions of radiation therapy. All patients received standard radiation therapy (RT) with concurrent temozolomide followed by adjuvant temozolomide. Imaging for response assessment consisted of MR scans every 2 months. Progression-free survival was defined by the criteria of MacDonald et al. MRSI images obtained at initial simulation were analyzed for choline/N-acetylaspartate ratios (Cho/NAA) on a voxel-by-voxel basis with abnormal activity defined as Cho/NAA ≥2. These images were compared on anatomically matched MRSI data collected after 3 weeks of RT. Changes in Cho/NAA between pretherapy and third-week RT scans were tested using Wilcoxon matched-pairs signed rank tests and correlated with progression-free survival, radiation dose and location of recurrence using Cox proportional hazards regression. Results: After a median follow-up time of 8.6 months, 50% of patients had experienced progression based on imaging. Patients with a decreased or stable mean or median Cho/NAA values had less risk of progression (P<.01). Patients with an increase in mean or median Cho/NAA values at the third-week RT scan had a significantly greater chance of early progression (P<.01). An increased Cho/NAA at the third-week MRSI scan carried a hazard ratio of 2.72 (95% confidence interval, 1.10-6.71; P=.03). Most patients received the prescription dose of RT to the Cho/NAA ≥2 volume, where recurrence most often occurred. Conclusion: Change in mean and median Cho/NAA detected at 3 weeks was a significant predictor of early progression. The potential impact for risk-adaptive therapy based on early spectroscopic findings is suggested.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Preoperative Chemoradiation Therapy in Combination With Panitumumab for Patients With Resectable Esophageal Cancer: The PACT Study

Purpose: Preoperative chemoradiation therapy (CRT) has become the standard treatment strategy for patients with resectable esophageal cancer. This multicenter phase 2 study investigated the efficacy of the addition of the epidermal growth factor receptor (EGFR) inhibitor panitumumab to a preoperative CRT regimen with carboplatin, paclitaxel, and radiation therapy in patients with resectable esophageal cancer. Methods and Materials: Patients with resectable cT1N1M0 or cT2-3N0 to -2M0 tumors received preoperative CRT consisting of panitumumab (6 mg/kg) on days 1, 15, and 29, weekly administrations of carboplatin (area under the curve [AUC] = 2), and paclitaxel (50 mg/m{sup 2}) for 5 weeks and concurrent radiation therapy (41.4 Gy in 23 fractions, 5 days per week), followed by surgery. Primary endpoint was pathologic complete response (pCR) rate. We aimed at a pCR rate of more than 40%. Furthermore, we explored the predictive value of biomarkers (EGFR, HER 2, and P53) for pCR. Results: From January 2010 until December 2011, 90 patients were enrolled. Patients were diagnosed predominantly with adenocarcinoma (AC) (80%), T3 disease (89%), and were node positive (81%). Three patients were not resected due to progressive disease. The primary aim was unmet, with a pCR rate of 22%. Patients with AC and squamous cell carcinoma reached a pCR of 14% and 47%, respectively. R0 resection was achieved in 95% of the patients. Main grade 3 toxicities were rash (12%), fatigue (11%), and nonfebrile neutropenia (11%). None of the biomarkers was predictive for response. Conclusions: The addition of panitumumab to CRT with carboplatin and paclitaxel was safe and well tolerated but could not improve pCR rate to the preset criterion of 40%.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

A Pilot Study of Hypofractionated Stereotactic Radiation Therapy and Sunitinib in Previously Irradiated Patients With Recurrent High-Grade Glioma

Purpose/Objective(s): Angiogenic blockade with irradiation may enhance the therapeutic ratio of radiation therapy (RT) through vascular normalization. We sought to determine the safety and toxicity profile of continuous daily-dosed sunitinib when combined with hypofractionated stereotactic RT (fSRT) for recurrent high-grade gliomas (rHGG). Methods and Materials: Eligible patients had malignant high-grade glioma that recurred or progressed after primary surgery and RT. All patients received a minimum of a 10-day course of fSRT, had World Health Organization performance status of 0 to 1, and a life expectancy of >3 months. During fSRT, sunitinib was administered at 37.5 mg daily. The primary endpoint was acute toxicity, and response was assessed via serial magnetic resonance imaging. Results: Eleven patients with rHGG were enrolled. The fSRT doses delivered ranged from 30 to 42 Gy in 2.5- to 3.75-Gy fractions. The median follow-up time was 40 months. Common acute toxicities included hematologic disorders, fatigue, hypertension, and elevated liver transaminases. Sunitinib and fSRT were well tolerated. One grade 4 mucositis toxicity occurred, and no grade 4 or 5 hypertensive events or intracerebral hemorrhages occurred. One patient had a nearly complete response, and 4 patients had stable disease for >9 months. Two patients (18%) remain alive and progression-free >3 years from enrollment. The 6-month progression-free survival was 45%. Conclusions: Sunitinib at a daily dose of 37.5 mg given concurrently with hypofractionated stereotactic reirradiation for rHGG yields acceptable toxicities and an encouraging 6-month progression-free survival.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Fat Composition Changes in Bone Marrow During Chemotherapy and Radiation Therapy

Purpose: To quantify changes in bone marrow fat fraction and determine associations with peripheral blood cell counts. Methods and Materials: In this prospective study, 19 patients received either highly myelotoxic treatment (radiation therapy plus cisplatin, 5-fluorouracil mitomycin C [FU/MMC], or cisplatin/5-FU/cetuximab) or less myelotoxic treatment (capecitabine-radiation therapy or no concurrent chemotherapy). Patients underwent MR imaging and venipuncture at baseline, midtreatment, and posttreatment visits. We performed mixed effects modeling of the mean proton density fat fraction (PDFF[%]) by linear time, treatment, and vertebral column region (lumbar [L]4-sacral [S]2 vs thoracic [T]10-L3 vs cervical[C]3-T9), while controlling for cumulative mean dose and other confounders. Spearman rank correlations were performed by white blood cell (WBC) counts versus the differences in PDFF(%) before and after treatment. Results: Cumulative mean dose was associated with a 0.43% per Gy (P=.004) increase in PDFF(%). In the highly myelotoxic group, we observed significant changes in PDFF(%) per visit within L4-S2 (10.1%, P<.001) and within T10-L3 (3.93%, P=.01), relative to the reference C3-T9. In the less myelotoxic group, we did not observe significant changes in PDFF(%) per visit according to region. Within L4-S2, we observed a significant difference between treatment groups in the change in PDFF(%) per visit (5.36%, P=.04). Rank correlations of the inverse log differences in WBC versus the differences in PDFF(%) overall and within T10-S2 ranged from 0.69 to 0.78 (P<.05). Rank correlations of the inverse log differences in absolute neutrophil counts versus the differences in PDFF(%) overall and within L4-S2 ranged from 0.79 to 0.81 (P<.05). Conclusions: Magnetic resonance imaging fat quantification is sensitive to marrow composition changes that result from chemoradiation therapy. These changes are associated with peripheral blood cell counts. This study supports a rationale for bone marrow-sparing treatment planning to reduce the risk of hematologic toxicity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Significance of ERBB2 Overexpression in Therapeutic Resistance and Cancer-Specific Survival in Muscle-Invasive Bladder Cancer Patients Treated With Chemoradiation-Based Selective Bladder-Sparing Approach

Purpose: To investigate the associations of ERBB 2 overexpression with chemoradiation therapy (CRT) resistance and cancer-specific survival (CSS) in muscle-invasive bladder cancer (MIBC) patients treated with the CRT-based bladder-sparing protocol. Methods and Materials: From 1997 to 2012, 201 patients with cT2-4aN0M0 bladder cancer were treated with CRT (40 Gy with concurrent cisplatin) following transurethral resection of bladder tumor (TURBT). Basically, patients with tumors that showed good CRT response and were amenable to segmental resection underwent partial cystectomy (PC) with pelvic lymph node dissection for bladder preservation; otherwise, radical cystectomy (RC) was recommended. Included in this study were 119 patients in whom TURBT specimens were available for immunohistochemical analysis of ERBB 2 expression. Following CRT, 30 and 65 patients underwent PC or RC, respectively; the remaining 24 patients did not undergo cystectomy. Tumors were defined as CRT-resistant when patients did not achieve complete response after CRT. Associations of ERBB 2 overexpression with CRT resistance and CSS were evaluated. Results: CRT resistance was observed clinically in 56% (67 of 119 patients) and pathologically (in cystectomy specimens) in 55% (52 of 95 patients). ERBB 2 overexpression was observed in 45 patients (38%). On multivariate analysis, ERBB 2 overexpression was an independent predictor for CRT resistance clinically (odds ratio, 3.6; P=.002) and pathologically (odds ratio, 2.9; P=.031). ERBB 2 overexpression was associated with shorter CSS (5-year CSS rates, 56% vs 87% for the ERBB 2 overexpression group vs the others; P=.001). ERBB 2 overexpression was also an independent risk factor for bladder cancer death at all time points of our bladder-sparing protocol (pre-CRT, post-CRT, and post-cystectomy). Conclusions: ERBB 2 overexpression appears relevant to CRT resistance and unfavorable CSS in MIBC patients treated with the CRT-based bladder-sparing protocol. ERBB 2-targeting treatment may improve the outcomes of such patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Radiobiological Determination of Dose Escalation and Normal Tissue Toxicity in Definitive Chemoradiation Therapy for Esophageal Cancer

Purpose: This study investigated the trade-off in tumor coverage and organ-at-risk sparing when applying dose escalation for concurrent chemoradiation therapy (CRT) of mid-esophageal cancer, using radiobiological modeling to estimate local control and normal tissue toxicity. Methods and Materials: Twenty-one patients with mid-esophageal cancer were selected from the SCOPE1 database (International Standard Randomised Controlled Trials number 47718479), with a mean planning target volume (PTV) of 327 cm{sup 3}. A boost volume, PTV2 (GTV + 0.5 cm margin), was created. Radiobiological modeling of tumor control probability (TCP) estimated the dose required for a clinically significant (+20%) increase in local control as 62.5 Gy/25 fractions. A RapidArc (RA) plan with a simultaneously integrated boost (SIB) to PTV2 (RA{sub 62.5}) was compared to a standard dose plan of 50 Gy/25 fractions (RA{sub 50}). Dose-volume metrics and estimates of normal tissue complication probability (NTCP) for heart and lungs were compared. Results: Clinically acceptable dose escalation was feasible for 16 of 21 patients, with significant gains (>18%) in tumor control from 38.2% (RA{sub 50}) to 56.3% (RA{sub 62.5}), and only a small increase in predicted toxicity: median heart NTCP 4.4% (RA{sub 50}) versus 5.6% (RA{sub 62.5}) P<.001 and median lung NTCP 6.5% (RA{sub 50}) versus 7.5% (RA{sub 62.5}) P<.001. Conclusions: Dose escalation to the GTV to improve local control is possible when overlap between PTV and organ-at-risk (<8% heart volume and <2.5% lung volume overlap for this study) generates only negligible increase in lung or heart toxicity. These predictions from radiobiological modeling should be tested in future clinical trials.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Long-term Outcomes in Treatment of Invasive Bladder Cancer With Concomitant Boost and Accelerated Hyperfractionated Radiation Therapy

Purpose: The aim of this study was to evaluate the long-term clinical efficacy and toxicity of concomitant boost and accelerated hyperfractionated radiation therapy (CBAHRT) in patients with invasive bladder cancer. Methods and Materials: Between October 1997 and September 2012, 334 patients with diagnoses of invasive bladder cancer were selected. These patients received CBAHRT as a bladder-conserving approach. The treatment consisted of a dose of 45 Gy/1.8 Gy to the whole pelvis with a daily concomitant boost of 1.5 Gy to the tumor. Total dose was 67.5 Gy in 5 weeks. A total of 32 patients (10.3%) had a diagnosis of stage T1, 202 (64.3%) were at stage T2, 46 (14.6%) were at stage T3a, 22 (7%) were at stage T3b, and 12 (3.8%) were at stage T4a. Results: The follow-up period was 33.1 months (range, 4.3-223.3 months). Grade 3 late intestinal toxicity was observed in 9 patients (2.9%), whereas grade 3 late urinary toxicity was observed in 8 patients (2.5%). The median overall survival (OS) was 26.3 months (95% confidence interval [CI]: 21.4-31.2). The 5-, 10, and 15-year OS rates were 32.1% (standard error [SE], ± 0.027), 17.9% (SE, ± 0.025) and 12.5% (SE, ± 0.028), respectively. The median cause-specific survival (CSS) was 42.1 months (95% CI: 28.7-55.5). The 5-, 10-, and 15-year CSS rates were 43.2% (SE, ± 0.03), 30.3% (SE, ± 0.03), and 28% (SE, ± 0.04), respectively. The median relapse-free survival (RFS) was 111.8 months (95% CI: 99.6-124). The 5-, 10-, and 15-year RFS rates were 61.9% (SE, ± 0.03), 57.6% (SE, ± 0.04), and 48.2% (SE, ± 0.07), respectively. Conclusions: The CBAHRT technique demonstrated acceptable toxicity and local control rates in patients with invasive bladder cancer, and this therapy facilitated bladder conservation. In selected patients, the CBAHRT technique is a practical alternative treatment option with acceptable 5-, 10-, and 15-year results in patients undergoing cystectomy as well as concurrent chemoradiation therapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Propensity Score–Matched Analysis of Comprehensive Local Therapy for Oligometastatic Non-Small Cell Lung Cancer That Did Not Progress After Front-Line Chemotherapy

Purpose: To retrospectively analyze factors influencing survival in patients with non-small cell lung cancer presenting with ≤3 synchronous metastatic lesions. Methods and Materials: We identified 90 patients presenting between 1998 and 2012 with non-small cell lung cancer and ≤3 metastatic lesions who had received at least 2 cycles of chemotherapy followed by surgery or radiation therapy before disease progression. The median number of chemotherapy cycles before comprehensive local therapy (CLT) (including concurrent chemoradiation as first-line therapy) was 6. Factors potentially affecting overall (OS) or progression-free survival (PFS) were evaluated with Cox proportional hazards regression. Propensity score matching was used to assess the efficacy of CLT. Results: Median follow-up time was 46.6 months. Benefits in OS (27.1 vs 13.1 months) and PFS (11.3 months vs 8.0 months) were found with CLT, and the differences were statistically significant when propensity score matching was used (P ≤ .01). On adjusted analysis, CLT had a statistically significant benefit in terms of OS (hazard ratio, 0.37; 95% confidence interval, 0.20-0.70; P ≤ .01) but not PFS (P=.10). In an adjusted subgroup analysis of patients receiving CLT, favorable performance status (hazard ratio, 0.43; 95% confidence interval, 0.22-0.84; P=.01) was found to predict improved OS. Conclusions: Comprehensive local therapy was associated with improved OS in an adjusted analysis and seemed to favorably influence OS and PFS when factors such as N status, number of metastatic lesions, and disease sites were controlled for with propensity score–matched analysis. Patients with favorable performance status had improved outcomes with CLT. Ultimately, prospective, randomized trials are needed to provide definitive evidence as to the optimal treatment approach for this patient population.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Multi-institutional Pooled Analysis on Adjuvant Chemoradiation in Pancreatic Cancer

Purpose: To determine the impact of chemoradiation therapy (CRT) on overall survival (OS) after resection of pancreatic adenocarcinoma. Methods and Materials: A multicenter retrospective review of 955 consecutive patients who underwent complete resection with macroscopically negative margins (R0-1) for invasive carcinoma (T1-4; N0-1; M0) of the pancreas was performed. Exclusion criteria included metastatic or unresectable disease at surgery, macroscopic residual disease (R2), treatment with intraoperative radiation therapy (IORT), and a histological diagnosis of no ductal carcinoma, or postoperative death (within 60 days of surgery). In all, 623 patients received postoperative radiation therapy (RT), 575 patients received concurrent chemotherapy (CT), and 462 patients received adjuvant CT. Results: Median follow-up was 21.0 months. Median OS after adjuvant CRT was 39.9 versus 24.8 months after no adjuvant CRT (P<.001) and 27.8 months after CT alone (P<.001). Five-year OS was 41.2% versus 24.8% with and without postoperative CRT, respectively. The positive impact of CRT was confirmed by multivariate analysis (hazard ratio [HR] = 0.72; confidence interval [CI], 0.60-0.87; P=.001). Adverse prognostic factors identified by multivariate analysis included the following: R1 resection (HR = 1.17; CI = 1.07-1.28; P<.001), higher pT stage (HR = 1.23; CI = 1.11-1.37; P<.001), positive lymph nodes (HR = 1.27; CI = 1.15-1.41; P<.001), and tumor diameter >20 mm (HR = 1.14; CI = 1.05-1.23; P=.002). Multivariate analysis also showed a better prognosis in patients treated in centers with >10 pancreatic resections per year (HR = 0.87; CI = 0.78-0.97; P=.014) Conclusion: This study represents the largest comparative study on adjuvant therapy in patients after resection of carcinoma of the pancreas. Overall survival was better in patients who received adjuvant CRT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Extended Field Intensity Modulated Radiation Therapy With Concomitant Boost for Lymph Node–Positive Cervical Cancer: Analysis of Regional Control and Recurrence Patterns in the Positron Emission Tomography/Computed Tomography Era

Purpose: Positron emission tomography/computed tomography (PET/CT) is commonly used for nodal staging in locally advanced cervical cancer; however the false negative rate for para-aortic disease are 20% to 25% in PET-positive pelvic nodal disease. Unless surgically staged, pelvis-only treatment may undertreat para-aortic disease. We have treated patients with PET-positive nodes with extended field intensity modulated radiation therapy (IMRT) to address the para-aortic region prophylactically with concomitant boost to involved nodes. The purpose of this study was to assess regional control rates and recurrence patterns. Methods and Materials: Sixty-one patients with cervical cancer (stage IBI-IVA) diagnosed from 2003 to 2012 with PET-avid pelvic nodes treated with extended field IMRT (45 Gy in 25 fractions with concomitant boost to involved nodes to a median of 55 Gy in 25 fractions) with concurrent cisplatin and brachytherapy were retrospectively analyzed. The nodal location was pelvis-only in 41 patients (67%) and pelvis + para-aortic in 20 patients (33%). There were a total of 179 nodes, with a median number of positive nodes of 2 (range, 1-16 nodes) per patient and a median nodal size of 1.8 cm (range, 0.7-4.5 cm). Response was assessed by PET/CT at 12 to 16 weeks. Results: Complete clinical and imaging response at the first follow-up visit was seen in 77% of patients. At a mean follow-up time of 29 months (range, 3-116 months), 8 patients experienced recurrence. The sites of persistent/recurrent disease were as follows: cervix 10 (16.3%), regional nodes 3 (4.9%), and distant 14 (23%). The rate of para-aortic failure in patients with pelvic-only nodes was 2.5%. There were no significant differences in recurrence patterns by the number/location of nodes, largest node size, or maximum node standardized uptake value. The rate of late grade 3+ adverse events was 4%. Conclusions: Extended field IMRT was well tolerated and resulted in low regional recurrence in node-positive cervical cancer. The dose of 55 Gy in 25 fractions was effective in eradicating disease in involved nodes, with acceptable late adverse events. Distant metastasis is the predominant mode of failure, and the OUTBACK trial may challenge the presented paradigms.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Attenuation of the DNA Damage Response by Transforming Growth Factor-Beta Inhibitors Enhances Radiation Sensitivity of Non–Small-Cell Lung Cancer Cells In Vitro and In Vivo

Purpose: To determine whether transforming growth factor (TGF)-β inhibition increases the response to radiation therapy in human and mouse non–small-cell lung carcinoma (NSCLC) cells in vitro and in vivo. Methods and Materials: TGF-β–mediated growth response and pathway activation were examined in human NSCLC NCI-H1299, NCI-H292, and A549 cell lines and murine Lewis lung cancer (LLC) cells. Cells were treated in vitro with LY364947, a small-molecule inhibitor of the TGF-β type 1 receptor kinase, or with the pan-isoform TGF-β neutralizing monoclonal antibody 1D11 before radiation exposure. The DNA damage response was assessed by ataxia telangiectasia mutated (ATM) or Trp53 protein phosphorylation, γH2AX foci formation, or comet assay in irradiated cells. Radiation sensitivity was determined by clonogenic assay. Mice bearing syngeneic subcutaneous LLC tumors were treated with 5 fractions of 6 Gy and/or neutralizing or control antibody. Results: The NCI-H1299, A549, and LLC NSCLC cell lines pretreated with LY364947 before radiation exposure exhibited compromised DNA damage response, indicated by decreased ATM and p53 phosphorylation, reduced γH2AX foci, and increased radiosensitivity. The NCI-H292 cells were unresponsive. Transforming growth factor-β signaling inhibition in irradiated LLC cells resulted in unresolved DNA damage. Subcutaneous LLC tumors in mice treated with TGF-β neutralizing antibody exhibited fewer γH2AX foci after irradiation and significantly greater tumor growth delay in combination with fractionated radiation. Conclusions: Inhibition of TGF-β before radiation attenuated DNA damage recognition and increased radiosensitivity in most NSCLC cells in vitro and promoted radiation-induced tumor control in vivo. These data support the rationale for concurrent TGF-β inhibition and RT to provide therapeutic benefit in NSCLC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Evaluating Tumor Response of Non-Small Cell Lung Cancer Patients With {sup 18}F-Fludeoxyglucose Positron Emission Tomography: Potential for Treatment Individualization

Objective: To assess early tumor responsiveness and the corresponding effective radiosensitivity for individual patients with non-small cell lung cancer (NSCLC) based on 2 successive {sup 18}F-fludeoxyglucose positron emission tomography (FDG-PET) scans. Methods and Materials: Twenty-six NSCLC patients treated in Maastricht were included in the study. Fifteen patients underwent sequential chemoradiation therapy, and 11 patients received concomitant chemoradiation therapy. All patients were imaged with FDG before the start and during the second week of radiation therapy. The sequential images were analyzed in relation to the dose delivered until the second image. An operational quantity, effective radiosensitivity, α{sub eff}, was determined at the voxel level. Correlations were sought between the average α{sub eff} or the fraction of negative α{sub eff} values and the overall survival at 2 years. Separate analyses were performed for the primary gross target volume (GTV), the lymph node GTV, and the clinical target volumes (CTVs). Results: Patients receiving sequential treatment could be divided into responders and nonresponders, using a threshold for the average α{sub eff} of 0.003 Gy{sup −1} in the primary GTV, with a sensitivity of 75% and a specificity of 100% (P<.0001). Choosing the fraction of negative α{sub eff} as a criterion, the threshold 0.3 also had a sensitivity of 75% and a specificity of 100% (P<.0001). Good prognostic potential was maintained for patients receiving concurrent chemotherapy. For lymph node GTV, the correlation had low statistical significance. A cross-validation analysis confirmed the potential of the method. Conclusions: Evaluation of the early response in NSCLC patients showed that it is feasible to determine a threshold value for effective radiosensitivity corresponding to good response. It also showed that a threshold value for the fraction of negative α{sub eff} could also be correlated with poor response. The proposed method, therefore, has potential to identify candidates for more aggressive strategies to increase the rate of local control and also avoid exposing to unnecessary aggressive therapies the majority of patients responding to standard treatment.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Impact of 1p/19q Codeletion and Histology on Outcomes of Anaplastic Gliomas Treated With Radiation Therapy and Temozolomide

Purpose: Anaplastic gliomas represent a heterogeneous group of primary high-grade brain tumors, and the optimal postoperative treatment remains controversial. In this report, we present our institutional data on the clinical outcomes of radiation therapy (RT) plus temozolomide (RT + TMZ) for anaplastic gliomas, stratified by histology and 1p/19q codeletion. Methods and Materials: A single-institution retrospective review was conducted of patients with supratentorial anaplastic oligodendroglioma (AO), mixed anaplastic oligoastrocytoma (AOA), and anaplastic astrocytoma (AA). After surgery, RT was delivered at a median total dose of 60 Gy (range, 31.6-63 Gy) in daily fractions. All patients received standard concurrent TMZ, with or without adjuvant TMZ. Histological/molecular subtypes were defined as codeleted AO/AOA, non-codeleted AO/AOA, and AA. Results: From 2000 to 2012, 111 cases met study criteria and were evaluable. Codeleted AO/AOA had superior overall survival (OS) to non-codeleted AO/AOA (91% vs 68% at 5 years, respectively, P=.02), whereas progression-free survival (PFS) was not significantly different (70% vs 46% at 5 years, respectively, P=.10). AA had inferior OS to non-codeleted AO/AOA (37% vs 68% at 5 years, respectively, P=.007) and inferior PFS (27% vs 46%, respectively, P=.03). On multivariate analysis, age, performance status, and histological or molecular subtype were independent predictors for both PFS and OS. Compared to historical controls, RT + TMZ provided comparable OS to RT with procarbazine, lomustine, and vincristine (RT + PCV) for codeleted AO/AOA, superior OS to RT alone for non-codeleted AO/AOA, and similar OS to RT alone for AA. Conclusions: RT + TMZ may be a promising treatment for both codeleted and non-codeleted AO/AOA, but its role for AA remains unclear.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

MRI-Guided High–Dose-Rate Intracavitary Brachytherapy for Treatment of Cervical Cancer: The University of Pittsburgh Experience

Purpose: Image-based brachytherapy is increasingly used for gynecologic malignancies. We report early outcomes of magnetic resonance imaging (MRI)-guided brachytherapy. Methods and Materials: Consecutive patient cases with FIGO stage IB1 to IVA cervical cancer treated at a single institution were retrospectively reviewed. All patients received concurrent cisplatin with external beam radiation therapy along with interdigitated high–dose-rate intracavitary brachytherapy. Computed tomography or MRI was completed after each application, the latter acquired for at least 1 fraction. High-risk clinical target volume (HRCTV) and organs at risk were identified by Groupe Européen de Curiethérapie and European SocieTy for Radiotherapy and Oncology guidelines. Doses were converted to equivalent 2-Gy doses (EQD{sub 2}) with planned HRCTV doses of 75 to 85 Gy. Results: From 2007 to 2013, 128 patients, median 52 years of age, were treated. Predominant characteristics included stage IIB disease (58.6%) with a median tumor size of 5 cm, squamous histology (82.8%), and no radiographic nodal involvement (53.1%). Most patients (67.2%) received intensity modulated radiation therapy (IMRT) at a median dose of 45 Gy, followed by a median brachytherapy dose of 27.5 Gy (range, 25-30 Gy) in 5 fractions. At a median follow up of 24.4 months (range, 2.1-77.2 months), estimated 2-year local control, disease-free survival, and cancer-specific survival rates were 91.6%, 81.8%, and 87.6%, respectively. Predictors of local failure included adenocarcinoma histology (P<.01) and clinical response at 3 months (P<.01). Among the adenocarcinoma subset, receiving HRCTV D{sub 90} EQD{sub 2} ≥84 Gy was associated with improved local control (2-year local control rate 100% vs 54.5%, P=.03). Grade 3 or greater gastrointestinal or genitourinary late toxicity occurred at a 2-year actuarial rate of 0.9%. Conclusions: This study constitutes one of the largest reported series of MRI-guided brachytherapy in North America, demonstrating excellent local control with acceptable morbidity. Dose escalation may be warranted when feasible for adenocarcinomas to offset the risk of local failure.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Phase 2 Study of Temozolomide-Based Chemoradiation Therapy for High-Risk Low-Grade Gliomas: Preliminary Results of Radiation Therapy Oncology Group 0424

Purpose: Radiation Therapy Oncology Group (RTOG) 0424 was a phase 2 study of a high-risk low-grade glioma (LGG) population who were treated with temozolomide (TMZ) and radiation therapy (RT), and outcomes were compared to those of historical controls. This study was designed to detect a 43% increase in median survival time (MST) from 40.5 to 57.9 months and a 20% improvement in 3-year overall survival (OS) rate from 54% to 65% at a 10% significance level (1-sided) and 96% power. Methods and Materials: Patients with LGGs with 3 or more risk factors for recurrence (age ≥40 years, astrocytoma histology, bihemispherical tumor, preoperative tumor diameter of ≥6 cm, or a preoperative neurological function status of >1) were treated with RT (54 Gy in 30 fractions) and concurrent and adjuvant TMZ. Results: From 2005 to 2009, 129 evaluable patients (75 males and 54 females) were accrued. Median age was 49 years; 91% had a Zubrod score of 0 or 1; and 69%, 25%, and 6% of patients had 3, 4, and 5 risk factors, respectively. Patients had median and minimum follow-up examinations of 4.1 years and 3 years, respectively. The 3-year OS rate was 73.1% (95% confidence interval: 65.3%-80.8%), which was significantly improved compared to that of prespecified historical control values (P<.001). Median survival time has not yet been reached. Three-year progression-free survival was 59.2%. Grades 3 and 4 adverse events occurred in 43% and 10% of patients, respectively. One patient died of herpes encephalitis. Conclusions: The 3-year OS rate of 73.1% for RTOG 0424 high-risk LGG patients is higher than that reported for historical controls (P<.001) and the study-hypothesized rate of 65%.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Randomized Phase 2 Trial of S1 and Oxaliplatin-Based Chemoradiotherapy With or Without Induction Chemotherapy for Esophageal Cancer

Purpose: To assess, in a randomized, phase 2 trial, the efficacy and safety of chemoradiotherapy with or without induction chemotherapy (ICT) of S1 and oxaliplatin for esophageal cancer. Patients and Methods: Patients with stage II, III, or IVA esophageal cancer were randomly allocated to either 2 cycles of ICT (oxaliplatin 130 mg/m{sup 2} on day 1 and S1 at 40 mg/m{sup 2} twice daily on days 1-14, every 3 weeks) followed by concurrent chemoradiotherapy (CCRT) (46 Gy, 2 Gy/d with oxaliplatin 130 mg/m{sup 2} on days 1 and 21 and S1 30 mg/m{sup 2} twice daily, 5 days per week during radiation therapy) and esophagectomy (arm A), or the same CCRT followed by esophagectomy without ICT (arm B). The primary endpoint was the pathologic complete response (pCR) rate. Results: A total of 97 patients were randomized (arm A/B, 47/50), 70 of whom underwent esophagectomy (arm A/B, 34/36). The intention-to-treat pCR rate was 23.4% (95% confidence interval [CI] 11.2-35.6%) in arm A and 38% (95% CI 24.5% to 51.5%) in arm B. With a median follow-up duration of 30.3 months, the 2-year progression-free survival rate was 58.4% in arm A and 58.6% in arm B, whereas the 2-year overall survival rate was 60.7% and 63.7%, respectively. Grade 3 or 4 thrombocytopenia during CCRT was more common in arm A than in arm B (35.4% vs 4.1%). The relative dose intensity of S1 (89.5% ± 20.6% vs 98.3% ± 5.2%, P=.005) and oxaliplatin (91.4% ± 16.8% vs 99.0% ± 4.2%, P=.007) during CCRT was lower in arm A compared with arm B. Three patients in arm A, compared with none in arm B, died within 90 days after surgery. Conclusions: Combination chemotherapy of S1 and oxaliplatin is an effective chemoradiotherapy regimen to treat esophageal cancer. However, we failed to show that the addition of ICT to the regimen can improve the pCR rate.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Safety and Palliative Efficacy of Single-Dose 8-Gy Reirradiation for Painful Local Failure in Patients With Stage IV Non-Small Cell Lung Cancer Previously Treated With Radical Chemoradiation Therapy

Purpose: To investigate the safety and efficacy of single-dose 8-Gy palliative chest reirradiation (CRI) in metastatic non-small cell lung cancer (M-NSCLC) patients with painful thoracic failures (TF) within the previous radiation portal. Patients and Methods: We retrospectively analyzed the clinical data of 78 M-NSCLC patients who received single-dose 8-Gy CRI for painful TF after concurrent chemoradiation therapy to a total radiation dose of 52 to 66 Gy between 2007 and 2012. Primary endpoints included significant pain relief (SPR) defined as a ≥2 point decrement in the Visual Analogue Scale for Pain inventory (VAS-P), time to pain relief, and duration of pain control. Secondary objectives were survival and prognostic factors. Results: Treatment was well tolerated, with only 5.1% grade 3 pneumonitis and 1.3% grade 2 esophagitis. Pre-CRI median and post-CRI minimum VAS-P were 7 and 3 (P<.001), respectively. SPR was noted in 67 (85.9%) patients, and only 3 (3.9%) scored progressive pain. Median time to lowest VAS-P and duration of pain control were 27 days and 6.1 months, respectively. Median overall survival (OS) was 7.7 months, and the 1-year OS rate was 26.5%. On multivariate analyses, lower Eastern Cooperative Oncology group score (1-2; P<.001), absence of anemia (P=.001), and fewer metastatic sites (1-2; P<.001) were found to be associated with longer OS. Conclusions: Single-dose 8-Gy CRI provides safe, effective, and durable pain palliation for TF in radically irradiated M-NSCLC patients. Because of its convenience, lower cost, and higher comfort, the present protocol can be considered an appropriate option for patients with limited life spans.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Stereotactic Radiosurgery for Melanoma Brain Metastases in Patients Receiving Ipilimumab: Safety Profile and Efficacy of Combined Treatment

Purpose: Ipilimumab (Ipi), a monoclonal antibody against cytotoxic T-lymphocyte antigen-4, has been shown to improve survival in patients with metastatic melanoma. In this single-institution study, we investigated the safety and efficacy of stereotactic radiosurgery (SRS) for patients with melanoma brain metastases (BMs) who also received Ipi. Methods and Materials: From 2005 to 2011, 46 patients with melanoma received Ipi and underwent single-fraction SRS for BMs. A total of 113 BMs (91% intact, 9% postoperative) were treated with a median dose of 21 Gy (range, 15-24 Gy). Ipi was given at 3 mg/kg (54%) or 10 mg/kg (46%) for a median of 4 doses (range, 1-21). Adverse events were recorded with the use of the Common Terminology Criteria for Adverse Events 3.0. Kaplan-Meier methods were used to estimate survival, and Cox regression was used to investigate associations. Results: Fifteen patients received SRS during Ipi, 19 received SRS before Ipi, and 12 received SRS after Ipi. Overall survival (OS) was significantly associated with the timing of SRS/Ipi (P=.035) and melanoma-specific graded prognostic assessment (P=.013). Patients treated with SRS during or before Ipi had better OS and less regional recurrence than did those treated with SRS after Ipi (1-year OS 65% vs 56% vs 40%, P=.008; 1-year regional recurrence 69% vs 64% vs 92%, P=.003). SRS during Ipi also yielded a trend toward less local recurrence than did SRS before or after Ipi (1-year local recurrence 0% vs 13% vs 11%, P=.21). On magnetic resonance imaging, an increase in BM diameter to >150% was seen in 50% of patients treated during or before Ipi but in only 13% of patients treated after Ipi. Grade 3 to 4 toxicities were seen in 20% of patients. Conclusion: Overall, the combination of Ipi and SRS appears to be well tolerated. Concurrent delivery of Ipi and SRS is associated with favorable locoregional control and possibly longer survival. It may also cause a temporary increase in tumor size, possibly because of an enhanced immunomodulatory effect.

62 RADIOLOGY AND NUCLEAR MEDICINE↗