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At least 145 records · Page 8

Integration of a Radiosensitivity Molecular Signature Into the Assessment of Local Recurrence Risk in Breast Cancer

Purpose: Recently, we developed radiosensitivity (RSI), a clinically validated molecular signature that estimates tumor radiosensitivity. In the present study, we tested whether integrating RSI with the molecular subtype refines the classification of local recurrence (LR) risk in breast cancer. Methods and Materials: RSI and molecular subtype were evaluated in 343 patients treated with breast-conserving therapy that included whole-breast radiation therapy with or without a tumor bed boost (dose range 45-72 Gy). The follow-up period for patients without recurrence was 10 years. The clinical endpoint was LR-free survival. Results: Although RSI did not uniformly predict for LR across the entire cohort, combining RSI and the molecular subtype identified a subpopulation with an increased risk of LR: triple negative (TN) and radioresistant (reference TN-radioresistant, hazard ratio [HR] 0.37, 95% confidence interval [CI] 0.15-0.92, P=.02). TN patients who were RSI-sensitive/intermediate had LR rates similar to those of luminal (LUM) patients (HR 0.86, 95% CI 0.47-1.57, P=.63). On multivariate analysis, combined RSI and molecular subtype (P=.004) and age (P=.001) were the most significant predictors of LR. In contrast, integrating RSI into the LUM subtype did not identify additional risk groups. We hypothesized that radiation dose escalation was affecting radioresistance in the LUM subtype and serving as a confounder. An increased radiation dose decreased LR only in the luminal-resistant (LUM-R) subset (HR 0.23, 95% CI 0.05-0.98, P=.03). On multivariate analysis, the radiation dose was an independent variable only in the LUMA/B-RR subset (HR 0.025, 95% CI 0.001-0.946, P=.046), along with age (P=.008), T stage (P=.004), and chemotherapy (P=.008). Conclusions: The combined molecular subtype–RSI identified a novel molecular subpopulation (TN and radioresistant) with an increased risk of LR after breast-conserving therapy. We propose that the combination of RSI and molecular subtype could be useful in guiding radiation therapy–based decisions in breast cancer.

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Brachytherapy Is Associated With Improved Survival in Inoperable Stage I Endometrial Adenocarcinoma: A Population-Based Analysis

Purpose: To assess the use of brachytherapy (BT) with or without external beam radiation (EBRT) in inoperable stage I endometrial adenocarcinoma in the United States and to determine the effect of BT on overall survival (OS) and cause-specific survival (CSS). Methods and Materials: Data between 1998 and 2011 from the National Cancer Institute's Surveillance, Epidemiology and End Results database were analyzed. Coarsened exact matching was used to adjust for differences in age and grade between patients who received BT and those who did not. Prognostic factors affecting OS and CSS were evaluated using the Kaplan-Meier product-limit method and a Cox proportional hazards regression model. Results: A total of 460 patients with inoperable stage I endometrial adenocarcinoma treated with radiation therapy were identified. Radiation consisted of either EBRT (n=260) or BT with or without EBRT (n=200). The only factor associated with BT use was younger patient age (median age, 72 vs 76 years, P=.001). Patients who received BT had a higher 3-year OS (60% vs 47%, P<.001) and CSS (82% vs 74%, P=.032) compared with those who did not. On multivariate analysis, BT use was independently associated with an improved OS (hazard ratio [HR] 0.67, 95% confidence interval [CI] 0.52-0.87) and CSS (HR 0.61, 95% CI 0.39-0.93). When patients were matched on age, BT use remained significant on multivariate analysis for OS (HR 0.65, 95% CI 0.48-0.87) and CSS (HR 0.52, 95% CI 0.31-0.84). When matched on age and grade, BT remained independently associated with improved OS and CSS (OS HR 0.62, 95% CI 0.46-0.83; CSS HR 0.57, 95% CI 0.34-0.92). Conclusion: Brachytherapy is independently associated with improved OS and CSS. It should be considered as part of the treatment regimen for stage I inoperable endometrial cancer patients undergoing radiation.

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Radiation Dose–Dependent Hippocampal Atrophy Detected With Longitudinal Volumetric Magnetic Resonance Imaging

Purpose: After radiation therapy (RT) to the brain, patients often experience memory impairment, which may be partially mediated by damage to the hippocampus. Hippocampal sparing in RT planning is the subject of recent and ongoing clinical trials. Calculating appropriate hippocampal dose constraints would be improved by efficient in vivo measurements of hippocampal damage. In this study we sought to determine whether brain RT was associated with dose-dependent hippocampal atrophy. Methods and Materials: Hippocampal volume was measured with magnetic resonance imaging (MRI) in 52 patients who underwent fractionated, partial brain RT for primary brain tumors. Study patients had high-resolution, 3-dimensional volumetric MRI before and 1 year after RT. Images were processed using software with clearance from the US Food and Drug Administration and Conformité Européene marking for automated measurement of hippocampal volume. Automated results were inspected visually for accuracy. Tumor and surgical changes were censored. Mean hippocampal dose was tested for correlation with hippocampal atrophy 1 year after RT. Average hippocampal volume change was also calculated for hippocampi receiving high (>40 Gy) or low (<10 Gy) mean RT dose. A multivariate analysis was conducted with linear mixed-effects modeling to evaluate other potential predictors of hippocampal volume change, including patient (random effect), age, hemisphere, sex, seizure history, and baseline volume. Statistical significance was evaluated at α = 0.05. Results: Mean hippocampal dose was significantly correlated with hippocampal volume loss (r=−0.24, P=.03). Mean hippocampal volume was significantly reduced 1 year after high-dose RT (mean −6%, P=.009) but not after low-dose RT. In multivariate analysis, both RT dose and patient age were significant predictors of hippocampal atrophy (P<.01). Conclusions: The hippocampus demonstrates radiation dose–dependent atrophy after treatment for brain tumors. Quantitative MRI is a noninvasive imaging technique capable of measuring radiation effects on intracranial structures. This technique could be investigated as a potential biomarker for development of reliable dose constraints for improved cognitive outcomes.

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Five-Year Biochemical Results, Toxicity, and Patient-Reported Quality of Life After Delivery of Dose-Escalated Image Guided Proton Therapy for Prostate Cancer

Purpose: To report clinical outcomes in patients treated with image guided proton therapy (PT) for localized prostate cancer. Methods and Materials: The medical records of 1327 men were reviewed. Each man was enrolled on an outcomes tracking study. Dual enrollment on a prospective clinical trial was allowed. Each patient was treated for localized prostate cancer with PT at our institution between 2006 and 2010. Ninety-eight percent of patients received 78 Gy (radiobiological equivalent [RBE]) or higher; 18% received androgen deprivation therapy (ADT). The 5-year freedom from biochemical progression (FFBP), distant metastasis-free survival, and cause-specific survival rates are reported for each risk group. Data on patient-reported quality of life and high-grade toxicities were prospectively collected and reported. A multivariate analysis was performed to identify clinical predictors of biochemical failure and urologic toxicity. Results: The median follow-up time was 5.5 years. The 5-year FFBP rates were 99%, 94%, and 74% in low-risk, intermediate-risk, and high-risk patients, respectively. The actuarial 5-year rates of late grade 3+ Common Terminology Criteria for Adverse Events, version 4.0, gastrointestinal (GI) and genitourinary (GU) toxicity were 0.6% and 2.9%, respectively. Multivariate analysis showed a significant correlation between grade 3+ GU toxicity and pretreatment prostate reductive procedures (P<.0001), prostate volume (P=.0085), pretreatment α-blockers (P=.0067), diabetes (P=.0195), and dose–volume histogram parameters (P=.0208). The median International Prostate Symptom Scores pretreatment scores and scores at 5 years after treatment were 7 and 7, respectively. The mean Expanded Prostate Cancer Index Composite (EPIC) scores significantly declined for sexual summary for patients not receiving ADT (from 67 to 53) between baseline and 5 years. Conclusions: Image guided PT provided excellent biochemical control rates for patients with localized prostate cancer. The actuarial rates of high-grade toxicity were low after PT. From pretreatment to 5 years of follow-up, a significant decline was found only in mean EPIC sexual summary scores. Prospective clinical studies are needed to determine the comparative effectiveness of PT and other radiation treatment strategies.

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Predictors of Individual Tumor Local Control After Stereotactic Radiosurgery for Non-Small Cell Lung Cancer Brain Metastases

Purpose: To evaluate local control rates and predictors of individual tumor local control for brain metastases from non-small cell lung cancer (NSCLC) treated with stereotactic radiosurgery (SRS). Methods and Materials: Between June 1998 and May 2011, 401 brain metastases in 228 patients were treated with Gamma Knife single-fraction SRS. Local failure was defined as an increase in lesion size after SRS. Local control was estimated using the Kaplan-Meier method. The Cox proportional hazards model was used for univariate and multivariate analysis. Receiver operating characteristic analysis was used to identify an optimal cutpoint for conformality index relative to local control. A P value <.05 was considered statistically significant. Results: Median age was 60 years (range, 27-84 years). There were 66 cerebellar metastases (16%) and 335 supratentorial metastases (84%). The median prescription dose was 20 Gy (range, 14-24 Gy). Median overall survival from time of SRS was 12.1 months. The estimated local control at 12 months was 74%. On multivariate analysis, cerebellar location (hazard ratio [HR] 1.94, P=.009), larger tumor volume (HR 1.09, P<.001), and lower conformality (HR 0.700, P=.044) were significant independent predictors of local failure. Conformality index cutpoints of 1.4-1.9 were predictive of local control, whereas a cutpoint of 1.75 was the most predictive (P=.001). The adjusted Kaplan-Meier 1-year local control for conformality index ≥1.75 was 84% versus 69% for conformality index <1.75, controlling for tumor volume and location. The 1-year adjusted local control for cerebellar lesions was 60%, compared with 77% for supratentorial lesions, controlling for tumor volume and conformality index. Conclusions: Cerebellar tumor location, lower conformality index, and larger tumor volume were significant independent predictors of local failure after SRS for brain metastases from NSCLC. These results warrant further investigation in a prospective setting.

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Radiotherapy for Stage II and Stage III Breast Cancer Patients With Negative Lymph Nodes After Preoperative Chemotherapy and Mastectomy

Purpose: To evaluate the effect of postmastectomy radiotherapy (PMRT) in Stage II-III breast cancer patients with negative lymph nodes (pN0) after neoadjuvant chemotherapy (NAC). Patients and Materials: Of 1,054 breast cancer patients treated with NAC at our institution between 1990 and 2004, 134 had pN0 status after NAC and mastectomy. The demographic data, tumor characteristics, metastatic sites, and treatments were prospectively recorded. The effect of PMRT on locoregional recurrence-free survival and overall survival (OS) was evaluated by multivariate analysis, including known prognostic factors. Results: Of the 134 eligible patients, 78 (58.2%) received PMRT and 56 (41.8%) did not. At a median follow-up time of 91.4 months, the 5-year locoregional recurrence-free survival and OS rate was 96.2% and 88.3% with PMRT and 92.5% and 94.3% without PMRT, respectively (p = NS). The corresponding values at 10 years were 96.2% and 77.2% with PMRT and 86.8% and 87.7% without PMRT (p = NS). On multivariate analysis, PMRT had no effect on either locoregional recurrence-free survival (hazard ratio, 0.37; 95% confidence interval, 0.09-1.61; p = .18) or OS (hazard ratio, 2.06; 95% confidence interval, 0.71-6; p = .18). This remained true in the subgroups of patients with clinical Stage II or Stage III disease at diagnosis. A trend was seen toward poorer OS among patients who had not had a pathologic complete in-breast tumor response after NAC (hazard ratio, 6.65; 95% confidence interval, 0.82-54.12; p = .076). Conclusions: The results from the present retrospective study showed no increase in the risk of distant metastasis, locoregional recurrence, or death when PMRT was omitted in breast cancer patients with pN0 status after NAC and mastectomy. Whether the omission of PMRT is acceptable for these patients should be addressed prospectively.

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Outcomes of Post Mastectomy Radiation Therapy in Patients Receiving Axillary Lymph Node Dissection After Positive Sentinel Lymph Node Biopsy

Purpose: We sought to determine the rate of postmastectomy radiation therapy (PMRT) among women treated with axillary lymph node dissection (ALND) after positive sentinel lymph node (SLN) biopsy results and to establish the effect of negative ALND results and PMRT on locoregional recurrence (LRR) and overall survival (OS). Methods and Materials: All patients were treated with mastectomy and ALND after positive SLN biopsy results. All patients had clinical N0 or NX disease at the time of mastectomy and received no neoadjuvant therapy. The presence of lymphovascular space invasion, presence of multifocality, number of positive SLNs and non-SLNs, clinical and pathologic stage, extranodal extension, age, and use of PMRT were evaluated for significance regarding the rates of OS and LRR. Results: A total of 345 patients were analyzed. ALND after positive SLN biopsy results was negative in 235 patients (68.1%), and a total of 112 patients (32.5%) received radiation therapy. On multivariate analysis, only pathologic stage III predicted for lower OS (hazard ratio, 3.32; P<.001). The rate of 10-year freedom from LRR was 87.9% and 95.3% in patients with positive ALND results and patients with negative ALND results, respectively. In patients with negative ALND results with ≥3 positive SLNs, the rate of freedom from LRR was 74.7% compared with 96.7% in those with <3 positive SLNs (P=.009). In patients with negative ALND results, ≥3 positive SLNs predicted for an increase in LRR on multivariate analysis (hazard ratio, 10.10; P=.034). Conclusions: A low proportion of cT1-2, N0 patients with positive SLNs who undergo mastectomy receive PMRT after ALND. Even in this low-risk cohort, patients with ≥3 positive SLNs and negative ALND results are at increased risk of LRR and may benefit from PMRT.

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Identifying Patients Who Are Unsuitable for Accelerated Partial Breast Irradiation Using Three-dimensional External Beam Conformal Techniques

Purpose: Several recent studies reported that severe late toxicities including soft-tissue fibrosis and fat necrosis are present in patients treated with accelerated partial breast irradiation (APBI) and that these toxicities are associated with the large volume of tissue targeted by high-dose irradiation. The present study was performed to clarify which patients are unsuitable for APBI to avoid late severe toxicities. Methods and Materials: Study subjects comprised 50 consecutive patients with Stage 0-II unilateral breast cancer who underwent breast-conserving surgery, and in whom five or six surgical clips were placed during surgery. All patients were subsequently replanned using three-dimensional conformal radiotherapy (3D-CRT) APBI techniques according to the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-39 and Radiation Therapy Oncology Group (RTOG) 0413 protocol. The beam arrangements included mainly noncoplanar four- or five-field beams using 6-MV photons alone. Results: Dose-volume histogram (DVH) constraints for normal tissues according to the NSABP/RTOG protocol were satisfied in 39 patients (78%). Multivariate analysis revealed that only long craniocaudal clip distance (CCD) was correlated with nonoptimal DVH constraints (p = 0.02), but that pathological T stage, anteroposterior clip distance (APD), site of ipsilateral breast (IB) (right/left), location of the tumor (medial/lateral), and IB reference volume were not. DVH constraints were satisfied in 20% of patients with a long CCD ({>=}5.5 cm) and 92% of those with a short CCD (p < 0.0001). Median IB reference volume receiving {>=}50% of the prescribed dose (IB-V{sub 50}) of all patients was 49.0% (range, 31.4-68.6). Multivariate analysis revealed that only a long CCD was correlated with large IB-V{sub 50} (p < 0.0001), but other factors were not. Conclusion: Patients with long CCDs ({>=}5.5 cm) might be unsuitable for 3D-CRT APBI because of nonoptimal DVH constraints and large IB-V{sub 50}.

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Retrospective Comparison of Chemoradiotherapy Followed by Adjuvant Chemotherapy, With or Without Prior Gliadel Implantation (Carmustine) After Initial Surgery in Patients With Newly Diagnosed High-Grade Gliomas

Purpose: Retrospective study of patients treated for high-grade glioma, with or without biodegradable carmustine wafers and according to the Stupp protocol. Methods and Materials: Between May 2007 and June 2008, 65 patients underwent surgery for high-grade glioma, 28 had implantation of Gliadel and 37 patients did not. Patients received radiotherapy with concomitant temozolomide followed by 5 consecutive days of temozolomide every month for 6 months. Results: Overall median follow-up was 17.1 months; the median relapse-free survival (RFS) was 14 months with a RFS of 54% at 12 months, and 38% at 24 months. For patient with and without Gliadel, median and 1-year RFS were 12.9 months and 52% vs. 14 months and 42%, respectively (p = 0.89). According to pathology, Gliadel did not influence RFS of patients with Grade III or glioblastoma. However, for all patients, in multivariate analysis, non-methylated methylguanine methyltransferase (MGMT) was the only unfavorable prognostic factor of RFS (p = 0.017; HR 2.8; CI [1.2-7]). Median overall survival (OS) was 20.8 months; the OS rate at 12 months was 78.5%, and at 24 months 35.4%. For patients treated with and without Gliadel, median and 1-year OS were 20.6 months and 78.6% vs. 20.8 months and 78.4%, respectively. According to pathology, Gliadel did not influence OS of patients with Grade III or glioblastoma. For all patients, in multivariate analysis, unfavorable prognosticators for OS were non-methylated MGMT (p = 0.001; HR: 6.5; CI [2-20]) and irradiation dose <60 Gy (p = 0.02; HR: 6.3; CI [2-20]). With carmustine wafers, before irradiation, median gross tumor volume plus edema was 84 mL (27-229), whereas it was 68 mL (10-362) without carmustine (p = nonsignificant). Four cases of Grade 3 thrombopenia occurred, all in the carmustine wafer group. Conclusion: In patients with high-grade gliomas, adding Gliadel before performing a Stupp protocol did not improve survival.

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Nuclear NF-κB Expression Correlates With Outcome Among Patients With Head and Neck Squamous Cell Carcinoma Treated With Primary Chemoradiation Therapy

Background: To examine whether nuclear NF-κB expression correlates with outcome in patients with head and neck squamous cell carcinoma (HNSCC) treated with primary chemoradiation therapy (CRT). Methods and Materials: Between 2007 and 2010, 101 patients with locally advanced primary HNSCC were treated with definitive simultaneous CRT. Pretreatment biopsy specimens were analyzed for NF-κB p65 (RelA) nuclear immunoreactivity. A sample was assigned to be positive with more than 5% positive nuclear expression. The predictive relevance of NF-κB and clinicopathologic factors for overall survival (OS), progression-free survival (PFS), local progression-free survival (LPFS), and metastasis-free survival (DMFS) was examined by univariate and multivariate analysis. Results: No significant differences between the groups were observed with regard to age, sex, total radiation dose, fractionation mode, total chemotherapy applied, T stage or grading. Patients with p65 nuclear positive biopsy specimens showed significantly a higher rate of lymph node metastasis (cN2c or cN3 status, P=.034). Within a mean follow-up time of 25 months (range, 2.33-62.96 months) OS, PFS, and DMFS were significantly poorer in the p65 nuclear positive group (P=.008, P=.027, and P=.008, respectively). These correlations remained significant in multivariate analysis. Conclusion: NF-κB/p65 nuclear expression is associated with increased lymphatic and hematogenous tumor dissemination and decreased survival in HNSCC patients treated with primary CRT. Our results may foster further investigation of a predictive relevance of NF-κB/p65 and its role as a suitable target for a molecular-based targeted therapy in HNSCC cancer.

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Involvement of Difference in Decrease of Hemoglobin Level in Poor Prognosis of Stage I and II Nasopharyngeal Carcinoma: Implication in Outcome of Radiotherapy

Purpose: To investigate the effect of hemoglobin (Hb) concentration and the difference in its decrease during treatment on outcome of radiotherapy (RT) alone for patients with Stage I and II nasopharyngeal carcinoma. Methods and Materials: A total of 572 patients with Stage I-II nasopharyngeal carcinoma with RT alone between January 2001 and December 2004 were retrospectively analyzed. Patient characteristics, tumor variables, and Hb level, including pre-RT Hb, mid-RT Hb, and dynamic change of Hb between pre- and post- RT and its difference in decrease ( White-Up-Pointing-Small-Triangle Hb) were subjected to univariate and multivariable analysis to identify factors that predict disease-specific survival (DSS), local regional recurrence-free survival (LRFS), and metastases-free survival (MFS). Results: The 5-year DSS was poorer in the Hb continuous decrease group than in the Hb noncontinuous decrease group (84% vs. 89%; p = 0.008). There was poorer 5-year DSS in patients with White-Up-Pointing-Small-Triangle Hb of >11.5 g/L than in those with White-Up-Pointing-Small-Triangle Hb of {<=}11.5 g/L (82% vs. 89%; p = 0.001), and poorer LRFS (79% vs. 83%; p = 0.035). Univariate and multivariate analysis showed that Hb decrease difference with greater than 11.5 g/L was an independent prognostic factor for DSS and LRFS. Conclusions: The difference in decrease of Hb level during the course of radiation treatment appeared as a poor prognostic factor in Stage I and II nasopharyngeal carcinoma patients.

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Prognostic Value of External Beam Radiation Therapy in Patients Treated With Surgical Resection and Intraoperative Electron Beam Radiation Therapy for Locally Recurrent Soft Tissue Sarcoma: A Multicentric Long-Term Outcome Analysis

Background: A joint analysis of data from centers involved in the Spanish Cooperative Initiative for Intraoperative Electron Radiotherapy was performed to investigate long-term outcomes of locally recurrent soft tissue sarcoma (LR-STS) patients treated with a multidisciplinary approach. Methods and Materials: Patients with a histologic diagnosis of LR-STS (extremity, 43%; trunk wall, 24%; retroperitoneum, 33%) and no distant metastases who underwent radical surgery and intraoperative electron radiation therapy (IOERT; median dose, 12.5 Gy) were considered eligible for participation in this study. In addition, 62% received external beam radiation therapy (EBRT; median dose, 50 Gy). Results: From 1986 to 2012, a total of 103 patients from 3 Spanish expert IOERT institutions were analyzed. With a median follow-up of 57 months (range, 2-311 months), 5-year local control (LC) was 60%. The 5-year IORT in-field control, disease-free survival (DFS), and overall survival were 73%, 43%, and 52%, respectively. In the multivariate analysis, no EBRT to treat the LR-STS (P=.02) and microscopically involved margin resection status (P=.04) retained significance in relation to LC. With regard to IORT in-field control, only not delivering EBRT to the LR-STS retained significance in the multivariate analysis (P=.03). Conclusion: This joint analysis revealed that surgical margin and EBRT affect LC but that, given the high risk of distant metastases, DFS remains modest. Intensified local treatment needs to be further tested in the context of more efficient concurrent, neoadjuvant, and adjuvant systemic therapy.

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A Matched Control Analysis of Adjuvant and Salvage High-Dose Postoperative Intensity-Modulated Radiotherapy for Prostate Cancer

Purpose: It is unclear whether immediate adjuvant radiotherapy for high-risk disease at prostatectomy (capsule perforation, seminal vesicle invasion, and/or positive surgical margins) is equivalent to delayed salvage radiotherapy at biochemical recurrence. We performed a matched case analysis comparing high-dose adjuvant intensity modulated radiotherapy (A-IMRT) with salvage IMRT (S-IMRT). Methods and Materials: One hundred forty-four patients with high-risk disease at prostatectomy were referred for A-IMRT, and 134 patients with high-risk disease were referred at biochemical recurrence (rising prostate-specific antigen [PSA], following prostatectomy, above 0.2 ng/ml) for S-IMRT. Patients were matched in a 1:1 ratio according to preoperative PSA level, Gleason score, and pT stage. Median doses of 74 Gy and 76 Gy were prescribed for A-IMRT and S-IMRT, respectively. We report biochemical relapse free survival (bRFS) rates using the Kaplan-Meier method. Univariate and multivariate analyses were used to examine tumour- and treatment-related factors. Results: A total of 178 patients were matched (89:89). From the end of radiotherapy, the median follow-up was 36 months for both groups. The 3-year bRFS rate for the A-IMRT group was 90% compared to 65% for the S-IMRT group (p < 0.05). On multivariate analysis, S-IMRT, Gleason grades of {>=}4+3, perineural invasion, preoperative PSA level of {>=}10 ng/ml, and omission of androgen deprivation (AD) were independent predictors for a reduced bRFS (p < 0.05). From the date of surgery, the median follow-up was 43 and 60 months for A-IMRT and S-IMRT, respectively. The 3-year bRFS rate for A-IMRT was 91% compared to 79% for S-IMRT (p < 0.05). On multivariate analysis, Gleason grades of {>=}4+3, perineural invasion, and omission of AD were independent predictors for a reduced bRFS (p < 0.05). S-IMRT was no longer an independent prognostic factor (p = 0.08). Conclusions: High-dose A-IMRT significantly improves 3-year bRFS compared to S-IMRT. Gleason grades of {>=}4+3, perineural invasion, and omission of AD were independent prognostic factors for a decreased bRFS, both from the dates of surgery and from radiotherapy.

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Lung Radiofrequency Ablation for the Treatment of Unresectable Recurrent Non-Small-Cell Lung Cancer After Surgical Intervention

Purpose: A retrospective evaluation was done of clinical utility of lung radiofrequency (RF) ablation in recurrent non-small-cell lung cancer (NSCLC) after surgical intervention. Methods: During May 2003 to October 2010, 44 consecutive patients (26 male and 18 female) received curative lung RF ablation for 51 recurrent NSCLC (mean diameter 1.7 {+-} 0.9 cm, range 0.6 to 4.0) after surgical intervention. Safety, tumor progression rate, overall survival, and recurrence-free survival were evaluated. Prognostic factors were evaluated in multivariate analysis. Results: A total of 55 lung RF sessions were performed. Pneumothorax requiring pluerosclerosis (n = 2) and surgical suture (n = 1) were the only grade 3 or 4 adverse events (5.5%, 3 of 55). During mean follow-up of 28.6 {+-} 20.3 months (range 1 to 98), local tumor progression was found in 5 patients (11.4%, 5 of 44). The 1-, 3-, and 5-year overall survival rates were 97.7, 72.9, and 55.7%, respectively. The 1- and 3-year recurrence-free survival rates were 76.7 and 41.1%, respectively. Tumor size and sex were independent significant prognostic factors in multivariate analysis. The 5-year survival rates were 73.3% in 18 women and 60.5% in 38 patients who had small tumors measuring {<=}3 cm. Conclusion: Our results suggest that lung RF ablation is a safe and useful therapeutic option for obtaining long-term survival in treated patients.

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Relationship Between Radiation Treatment Time and Overall Survival After Induction Chemotherapy for Locally Advanced Head-and-Neck Carcinoma: A Subset Analysis of TAX 324

Purpose: To analyze the relationship between overall survival (OS) and radiation treatment time (RTT) and overall treatment time (OTT) in a well-described sequential therapy paradigm for locally advanced head-and-neck carcinoma (LAHNC). Methods and Materials: TAX 324 is a Phase III study comparing TPF (docetaxel, cisplatin, and fluorouracil) with PF (cisplatin and fluorouracil) induction chemotherapy (IC) in LAHNC patients; both arms were followed by carboplatin-based chemoradiotherapy (CRT). Prospective radiotherapy quality assurance was performed. This analysis includes all patients who received three cycles of IC and a radiation dose of {>=} 70 Gy. Radiotherapy treatment time was analyzed as binary ({<=} 8 weeks vs. longer) and continuous (number of days beyond 8 weeks) functions. The primary analysis assessed the relationship between RTT, OTT, and OS, and the secondary analysis explored the association between treatment times and locoregional recurrence (LRR). Results: A total of 333 (of 501) TAX 324 patients met the criteria for inclusion in this analysis. There were no significant differences between the treatment arms in baseline or treatment characteristics. On multivariable analysis, PF IC, World Health Organization performance status of 1, non-oropharynx site, T3/4 stage, N3 status, and prolonged RTT (hazard ratio 1.63, p = 0.006) were associated with significantly inferior survival. Performance status, T3/4 disease, and prolonged RTT (odds ratio 1.68, p = 0.047) were independently and negatively related to LRR on multivariable analysis, whereas PF was not. Overall treatment time was not independently associated with either OS or LRR. Conclusions: In this secondary analysis of the TAX 324 trial, TPF IC remains superior to PF IC after controlling for radiotherapy delivery time. Even with optimal IC and concurrent chemotherapy, a non-prolonged RTT is a crucial determinant of treatment success. Appropriate delivery of radiotherapy after IC remains essential for optimizing OS in LAHNC.

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Fate of Manuscripts Rejected From the Red Journal

Purpose: To evaluate characteristics associated with higher rates of acceptance for original manuscripts submitted for publication to the International Journal of Radiation Oncology • Biology • Physics (IJROBP) and describe the fate of rejected manuscripts. Methods and Materials: Manuscripts submitted to the IJROBP from May 1, 2010, to August 31, 2010, and May 1, 2012, to August 31, 2012, were evaluated for author demographics and acceptance status. A PubMed search was performed for each IJROBP-rejected manuscript to ascertain whether the manuscript was ultimately published elsewhere. The Impact Factor of the accepting journal and the number of citations of the published manuscript were also collected. Results: Of the 500 included manuscripts, 172 (34.4%) were accepted and 328 (65.6%) were rejected. There was no significant difference in acceptance rates according to gender or degree of the submitting author, but there were significant differences seen based on the submitting author's country, rank, and h-index. On multivariate analysis, earlier year submitted (P<.0001) and higher author h-index (P=.006) remained significantly associated with acceptance into the IJROBP. Two hundred thirty-five IJROBP-rejected manuscripts (71.7%) were ultimately published in a PubMed-listed journal as of July 2014. There were no significant differences in any submitting author characteristics. Journals accepting IJROBP-rejected manuscripts had a lower median [interquartile range] 2013 impact factor compared with the IJROBP (2.45 [1.53-3.71] vs 4.176). The IJROBP-rejected manuscripts ultimately published elsewhere had a lower median [interquartile range] number of citations (1 [0-4] vs 6 [2-11]; P<.001), which persisted on multivariate analysis. Conclusions: The acceptance rate for manuscripts submitted to the IJROBP is approximately one-third, and approximately 70% of rejected manuscripts are ultimately published in other PubMed-listed journals, but these ultimate-destination journals usually have a lower impact factor, leading to fewer citations and overall visibility.

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Risk Factors of Infection and Role of Antibiotic Prophylaxis in Totally Implantable Venous Access Port Placement: Propensity Score Matching

Background: To evaluate risk factors of infection and effectiveness of preprocedural single-dose intravenous prophylactic antibiotic (PABX) during totally implantable venous access port (TIVAP) placement in preventing procedure-related infections. Methods: This was a retrospective single-institution multicenter study evaluating short-term (30-day) infection outcomes after TIVAP placement. Correlation between infection rates and clinical factors, including hematologic versus non-hematologic malignancy, inpatient versus outpatient status, single versus double lumen and PABX, was investigated using univariate and multivariable analysis in the overall study population as well as the propensity-score-matched cohort. Results: Overall, 5967 patients underwent TIVAP placement from 2005 to 2016, of which 3978 (67%) patients received PABX. On propensity score matching, 1952 patients with PABX were matched to the same number of patients without PABX. TIVAP was removed due to infection concern in 48 patients in unmatched and 30 patients in matched population. There was no difference in the rate of infection between those who received PABX and those who did not in both unmatched and matched population (p = 0.5387 and 0.9999). Although infection rate was significantly higher in patients who had TIVAP placement in inpatient setting (p < 0.0001), who received a double-lumen TIVAP (p < 0.0001), or who had hematologic malignancy (p = 0.0004) on univariate analysis, inpatient status was the sole factor associated with higher rate of TIVAP infection on multivariable analysis of both overall (odds ratio 2.31, p < 0.0001) and matched populations (odds ratio 4.36, p = 0.0004). Conclusion: Placement of TIVAP in inpatient setting increases the risk of TIVAP infection. PABX before TIVAP placement does not prevent short-term procedure-related infections.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Clinical Outcomes of 174 Nasopharyngeal Carcinoma Patients With Radiation-Induced Temporal Lobe Necrosis

Purpose: To retrospectively study the clinical outcomes of nasopharyngeal carcinoma patients with radiation-induced temporal lobe necrosis (TLN) treated with steroids, surgery, or observation only. Methods and Patients: We performed a retrospective analysis of 174 consecutive patients diagnosed with TLN between 1990 and 2008. Before 1998, symptomatic patients were treated with oral steroids, while asymptomatic patients were treated conservatively. After 1998, most symptomatic and asymptomatic patients with a large volume of necrosis were treated by intravenously pulsed-steroid therapy with a standardized protocol. We examined factors affecting grade 4 complication-free survival and overall survival. Outcomes of the three treatment groups, those receiving conservative treatment, those receiving oral steroid, and those receiving intravenous pulse steroid, were compared. Results: The mean follow-up time was 115 months. Rates of grade 4 complication-free survival at 2 years and at 5 years after diagnosis of TLN were 72.2% and 54.1%, respectively. The 2-year and 5-year overall survival rates were 57.5% and 35.4%, respectively. Multivariate analysis revealed that being symptomatic at diagnosis (relative risk [RR], 4.5; p = 0.0001), re-irradiation of the nasopharynx (NP) (RR, 1.56; p = 0.008), salvage brachytherapy to the NP (RR, 1.75; p = 0.012), and a short latency period before the diagnosis of TLN (RR, 0.96, p < 0.0001) were independent prognosticators of poor grade 4 complication-free survival. Patients with all four factors had a 100% risk of developing grade 4 complications within 5 years; whereas if no factor was present, the risk was 12.5%. Intravenous pulse steroid therapy was associated with a higher clinical response rate compared with conventional steroid therapy (p < 0.0001); however, it did not affect complication-free survival in multivariate analysis. Conclusions: TLN patients with good prognosticators could be observed without active treatment. Although treatment with intravenously pulsed steroid was associated with better clinical response than conventional steroid delivery, it did not affect the complication-free survival rate of TLN patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗