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PURPOSE: The combination of cisplatin and radiation or cetuximab and radiation improves overall survival of patients with locoregionally advanced head and neck carcinoma. NRG Oncology conducted a phase 3 trial to test the hypothesis that adding cetuximab to radiation and cisplatin would improve progression-free survival (PFS). METHODS AND MATERIALS: Eligible patients with American Joint Committee on Cancer sixth edition stage T2 N2a-3 M0 or T3–4 N0–3 M0 were accrued from November 2005 to March 2009 and randomized to receive radiation and cisplatin without (arm A) or with (arm B) cetuximab. Outcomes were correlated with patient and tumor features. Late reactions were scored using Common Terminology Criteria for Adverse Events (version 3). RESULTS: Of 891 analyzed patients, 452 with a median follow-up of 10.1 years were alive at analysis. The addition of cetuximab did not improve PFS (hazard ratio [HR], 1.06; 95% confidence interval [CI], 0.89–1.26; P = .74), with 10-year estimates of 43.6% (95% CI, 38.8–48.4) for arm A and 40.2% (95% CI, 35.4–45.0) for arm B. Cetuximab did not reduce locoregional failure (HR, 1.21; 95% CI, 0.95–1.53; P = .94) or distant metastasis (HR, 0.79; 95% CI, 0.54–1.14; P = .10) or improve overall survival (HR, 0.97; 95% CI, 0.80–1.16; P = .36). Cetuximab did not appear to improve PFS in either p16-positive oropharynx (HR, 1.30; 95% CI, 0.87–1.93) or p16-negative oropharynx or nonoropharyngeal primary (HR, 0.94; 95% CI, 0.73–1.21). Grade 3 to 4 late toxicity rates were 57.4% in arm A and 61.3% in arm B (P = .26). CONCLUSIONS: With a median follow-up of more than 10 years, this updated report confirms the addition of cetuximab to radiation therapy and cisplatin did not improve any measured outcome in the entire cohort or when stratifying by p16 status.

Every decision we make is accompanied by an estimate of the probability that our decision is accurate or appropriate. This probability estimate is termed our degree of decision confidence. Recent work has uncovered event-related potential (ERP) correlates of confidence both during decision formation and after a decision has been made. However, the interpretation of these findings is complicated by methodological issues related to ERP amplitude measurement that are prevalent across existing studies. To more accurately characterise the neural correlates of confidence, we presented participants with a difficult perceptual decision task that elicited a broad range of confidence ratings. We identified a frontal ERP component within an onset prior to the behavioural response, which exhibited more positive-going amplitudes in trials with higher confidence ratings. This frontal effect also biased measures of the centro-parietal positivity (CPP) component at parietal electrodes via volume conduction. Amplitudes of the error positivity (Pe) component that followed each decision were negatively associated with confidence for trials with decision errors, but not for trials with correct decisions, with Bayes factors providing moderate evidence for the null in the latter case. We provide evidence for both pre- and post-decisional neural correlates of decision confidence that are observed in trials with correct and erroneous decisions, respectively. Our findings suggest that certainty in having made a correct response is associated with frontal activity during decision formation, whereas certainty in having committed an error is instead associated with the post-decisional Pe component. These findings also highlight the possibility that some previously reported associations between decision confidence and CPP/Pe component amplitudes may have been a consequence of ERP amplitude measurement-related confounds. Re-analysis of existing datasets may be useful to test this hypothesis more directly.Highlights–We mapped the event-related potential correlates of decision confidence–A frontal component was associated with confidence during decision formation–The error positivity component was associated with confidence in error trials–The error positivity was not associated with confidence in correct response trials

PURPOSE Radiation dose to the neuroregenerative zone of the hippocampus has been found to be associated with cognitive toxicity. Hippocampal avoidance (HA) using intensity-modulated radiotherapy during whole-brain radiotherapy (WBRT) is hypothesized to preserve cognition. METHODS This phase III trial enrolled adult patients with brain metastases to HA-WBRT plus memantine or WBRT plus memantine. The primary end point was time to cognitive function failure, defined as decline using the reliable change index on at least one of the cognitive tests. Secondary end points included overall survival (OS), intracranial progression-free survival (PFS), toxicity, and patient-reported symptom burden. RESULTS Between July 2015 and March 2018, 518 patients were randomly assigned. Median follow-up for alive patients was 7.9 months. Risk of cognitive failure was significantly lower after HA-WBRT plus memantine versus WBRT plus memantine (adjusted hazard ratio, 0.74; 95% CI, 0.58 to 0.95; P = .02). This difference was attributable to less deterioration in executive function at 4 months (23.3% v 40.4%; P = .01) and learning and memory at 6 months (11.5% v 24.7% [ P = .049] and 16.4% v 33.3% [ P = .02], respectively). Treatment arms did not differ significantly in OS, intracranial PFS, or toxicity. At 6 months, using all data, patients who received HA-WBRT plus memantine reported less fatigue ( P = .04), less difficulty with remembering things ( P = .01), and less difficulty with speaking ( P = .049) and using imputed data, less interference of neurologic symptoms in daily activities ( P = .008) and fewer cognitive symptoms ( P = .01). CONCLUSION HA-WBRT plus memantine better preserves cognitive function and patient-reported symptoms, with no difference in intracranial PFS and OS, and should be considered a standard of care for patients with good performance status who plan to receive WBRT for brain metastases with no metastases in the HA region.

Purpose/Objective(s) To determine if hypofractionated post-operative prostate bed radiotherapy (HYPORT) does not increase patient-reported genitourinary (GU) or gastrointestinal (GI) toxicity over conventionally fractionated post-operative radiotherapy (COPORT). Materials/Methods Eligibility criteria were: 1) an undetectable PSA ( Results Between July 2017 and July 2018, 298 patients were screened and 296 were randomized: 144 to HYPORT and 152 to COPORT. Compliance with the EPIC was 100% at baseline, 83% at the end of RT, 77% at 6 months, 78% at 12 months, and 73% at 24 months. At the end of RT, the HYPORT and COPORT mean GU change scores were neither clinically significant nor significantly different and remained so at 6 and 12 months. The mean GI change scores for HYPORT and COPORT were both clinically significant and significantly different at the end of RT (HYPORT mean GI = -15.0 vs COPORT mean GI = -6.8 P ≤ 0.01). However, both the HYPORT and COPORT mean GI change scores clinically and statistically significant differences were resolved at 6 and 12 months. The 24-month mean GU and GI change scores for HYPORT and COPORT remained neither clinically nor statistically significant (HYPORT mean GU = -5.2 vs COPORT mean GU = -3.0, P = 0.81; HYPORT mean GI = -2.2 vs COPORT mean GI = -1.5, P = 0.12). With a median follow-up for censored patients of 2.1 years, there was no difference between HYPORT versus COPORT for biochemical failure defined as a PSA ≥ 0.4 ng/mL followed by a value higher than the first by any amount (2-yr actuarial, 12% vs 8%, P = 0.29) or local failure (2-yr actuarial, 0.7% vs 0.8%, P = 0.35). Conclusion HYPORT is non-inferior to COPORT in terms of late patient-reported GU or GI toxicity. More follow-up is needed to appropriately assess disease control endpoints. In some clinic scenarios, HYPORT may be considered an acceptable practice standard.

The use of radiotherapy in the treatment of prostate cancer has evolved from treatments utilizing large fields with hand placed blocks to radiotherapy treatments given with a linear accelerator moving around the patient on a robotic arm. These technologic developments have allowed radiation dose escalations resulting in improvements in disease and patient reported outcomes with longer biochemical disease-free survival (DFS) as well as improved quality of life. Increased costs have accompanied these technologic improvements with some private payers questioning the increased cost of the newer treatments and in some instances refusing to pay for some treatment modalities such as intensity-modulated radiotherapy (IMRT) or proton beam therapy (PBT). Cost-effectiveness analysis have been used in an attempt to illustrate these new treatments were cost-effective when compared to the older treatments. Cost-effectiveness analyses will need to be adapted in the current health care environment to provide an assessment of value as many payers, including medicare, move to a value-based reimbursement system.

Purpose: We observed that many of our helical therapy lung stereotactic body radiation therapy plans did not meet the Radiation Therapy Oncology Group (RTOG) recommended R50% (volume of 50% of the prescription dose/planning target volume), which characterizes the steepness of dose fall off. We hypothesized that despite not meeting R50%, helical therapy lung stereotactic body radiation therapy plans would confer similar local control and minimal side effects as previously reported using nonhelical treatment platforms. Materials and Methods: We report a retrospective review of all consecutive patients treated off-protocol with stereotactic body radiation therapy for peripheral lung lesions from 2008 to 2013 utilizing helical therapy. Seventy-four patients (81 lesions and 79 plans) were treated with doses ranging from 48 to 60 Gy in 3 to 5 fractions prescribed to the edge of the planning target volume. Results: Forty-eight (61%) plans had major deviation from R50%. Only 1 ( 95% planning target volume coverage by prescription dose, 7(8.6%) plans with 121% to 133% maximum dose, and lung V20 Gy

Introduction The impact of selective surgical resection for patients with esophageal cancer treated with definitive chemoradiation has not been clearly evaluated long-term. Methods NRG (National Surgical Adjuvant Breast and Bowel Project, Radiation Therapy Oncology Group, Gynecologic Oncology Group) Oncology Radiation Therapy Oncology Group 0246 was a multi-institutional, single-arm, open-label, nonrandomized phase II study that enrolled 43 patients from September 2003 to March 2008 with clinical stage T1–4N0–1M0 squamous cell or adenocarcinoma of the esophagus or gastroesophageal junction from 19 sites. Patients received induction chemotherapy with fluorouracil (650 mg/m 2 /d), cisplatin (15 mg/m 2 /d), and paclitaxel (200 mg/m 2 /d) for two cycles followed by concurrent chemoradiation consisting of 50.4 Gy of radiation (1.8 Gy per fraction) and daily fluorouracil (300 mg/m 2 /d) with cisplatin (15 mg/m 2 /d) over the first 5 days. After definitive chemoradiation, patients were evaluated for residual disease. Selective esophagectomy was considered only for patients with residual disease after chemoradiation (clinical incomplete response) or recurrent disease on surveillance. Results This report looks at the long-term outcome of this selective surgical strategy. With a median follow-up of 8.1 years (minimum to maximum for 12 alive patients 7.2–9.8 years), the estimated 5- and 7-year survival rates are 36.6% (95% confidence interval [CI]: 22.3–51.0) and 31.7% (95% CI: 18.3–46.0). Clinical complete response was achieved in 15 patients (37%), with 5- and 7-yearr survival rates of 53.3% (95% CI: 26.3–74.4) and 46.7% (95% CI: 21.2–68.7). Esophageal resection was not required in 20 of 41 patients (49%) on this trial. Conclusions The long-term results of NRG Oncology Radiation Therapy Oncology Group 0246 demonstrate promising efficacy of a selective surgical resection strategy and suggest the need for larger randomized studies to further evaluate this organ-preserving approach.

PURPOSE: Concomitant external-beam radiochemotherapy (5-fluorouracil-mitomycin C) has become the standard of care in anal cancer since the '90s. A pooled analysis of individual patient data from 7 major trials was performed quantifying the effect of radiation therapy (RT)-related parameters on the outcome of patients with anal cancer. MATERIALS AND METHODS: Pooling databases from combined modality trials, the impact of RT parameters (total dose, gap duration, OTT: overall treatment time) on outcome including locoregional failure (LRF), 5-year progression free survival (PFS) and toxicities were investigated. Individual patient data were received for 10/13 identified published studies conducted from 1987 to 2008 (n = 3031). A Cox regression model was used (landmark = 3 months after RT for first follow-up). RESULTS: After data inspection indicating severe heterogeneity between trials, only 1343 patients from 7/10 studies received were analysed (the most recent ones, since 1994; median follow-up = 4.1 years). A higher overall 5-year LRF rate [22.8% (95% confidence interval [CI] 22.3-27.3%)] significantly correlated with longer OTT (p = 0.03), larger tumour size (p

Purpose: Use of hypofractionation is increasing in radiation oncology because of several factors. The effects of increasing hypofractionation use on departments and staff currently based on fee-for-service models are not well studied. Methods: We modeled the effects of moving to hypofractionation for prostate, breast, and lung cancer and palliative treatments in a typical-sized hospital-based radiation oncology department. Year 2015 relative value unit (RVU) data were used to determine changes in reimbursement. The change in number of fractions was used to model the effects on machine volume, staff time, and workforce predictions. Results: The per-case marginal reduction in technical revenue was $1,777, $4,297, $9,041, and $9,498 for palliative and breast, prostate, and lung cancer cases, respectively. The physician reduction per case in RVUs was 5.22, 10.44, 43.02, and 43.02 respectively. A department could anticipate an annual reduction in technical revenue of $540,661 and a reduction in workflow of approximately five patients or 1 to 1.5 hours per day from a hypofractionation rate of 40%. Conclusion: The move to hypofractionation in the United States will lead to increased pressures on departments to address budget shortfalls resulting from the decrease in per-patient revenue. This may be done through a combination of an increase in patient volume, recognition of the increased skill sets required to deliver hypofractionated radiotherapy, delay in capital purchases, and/or reduction in staff. In a value-based environment, these evolutions should improve the value proposition of radiation oncology over a fee-for-service model.

PURPOSE: NRG CC001, a phase III trial of WBRT plus memantine with or without hippocampal avoidance, sought to evaluate the neuro-protective effects of avoiding the hippocampus using intensity-modulated radiotherapy. METHODS: Adult patients with brain metastases were stratified by RPA class and receipt of prior radiosurgery/surgery and randomized to WBRT+memantine (WBRT+M) versus hippocampal-avoidant WBRT+memantine (HA-WBRT+M) (30Gy in 10 fractions). Standardized NCF tests were performed at baseline, 2, 4, 6, and 12 months. The primary endpoint was time to NCF failure, defined as decline on at least one of the following tests using the reliable change index: Hopkins Verbal Learning Test-Revised, Trail Making Test, or Controlled Oral Word Association. Cumulative incidence was used to estimate time to NCF failure (death without NCF failure was treated as competing risk) with between-arms differences tested using Grays test. To detect an 11% absolute reduction in 6-month NCF failure, 382 analyzable patients were required for 90% power with two-sided =0.05. Due to possible non-compliance, the sample size was increased by 25% (510 patients). RESULTS: From July 2016 to March 2018, 518 patients were randomized. Median age was 61.5 years. Median follow-up for alive patients was 6.1 months. Treatment arms did not differ in grade3 toxicity, overall survival, intracranial progression, or baseline NCF. Time to NCF failure was significantly longer in favor of HA-WBRT+M (p=0.012). The 6-month NCF failure rates were 69.1% (95% CI:61.8–75.3%) vs. 58.0% (95% CI:50.2–64.9%) for WBRT+M vs. HA-WBRT+M, respectively. After adjusting for stratification factors, HA-WBRT+M (hazard ratio (HR)=0.73, 95%CI:0.56–0.94, p=0.016) and age 61 years (HR=0.61, 95%CI:0.46–0.81, p=0.0006) remained significant. CONCLUSION: Preliminary analysis confirms that conformal avoidance of the neuro-regenerative hippocampal stem cell compartment during WBRT preserves neurocognitive function while achieving similar intracranial control and survival. Supported by grants UG1CA189867 (NCORP), U10CA180868 (NRG Oncology Operations), DCP from the National Cancer Institute.

Purpose: A meta-analysis of sociodemographic variables and their association with late (>180 days from start of radiation therapy[RT]) bowel, bladder, and clustered bowel and bladder toxicities was conducted in patients with high-risk (clinical stages T2c-T4b or Gleason score 8-10 or prostate-specific antigen level >20) prostate cancer. Methods and materials: Three NRG trials (RTOG 9202, RTOG 9413, and RTOG 9406) that accrued from 1992 to 2000 were used. Late toxicities were measured with the Radiation Therapy Oncology Group Late Radiation Morbidity Scale. After controlling for study, age, Karnofsky Performance Status, and year of accrual, sociodemographic variables were added to the model for each outcome variable of interest in a stepwise fashion using the Fine-Gray regression models with an entry criterion of 0.05. Results: A total of 2432 patients were analyzed of whom most were Caucasian (76%), had a KPS score of 90 to 100 (92%), and received whole-pelvic RT+HT (67%). Of these patients, 13 % and 16% experienced late grade ≥2 bowel and bladder toxicities, respectively, and 2% and 3% experienced late grade ≥3 bowel and bladder toxicities, respectively. Late grade ≥2 clustered bowel and bladder toxicities were seen in approximately 1% of patients and late grade ≥3 clustered toxicities were seen in 2 patients (

BACKGROUND: Cost can be a major issue in therapeutic decision-making, and in particular for patients with locally advanced non-small cell lung cancer (LA-NSCLC). METHODS: The specific aim of this analysis was to evaluate the costs and outcomes of patients treated on Radiation Therapy Oncology Group (RTOG) 94-10, Medicare Part A and Part B costs from all for patients treated from 1991 to 1996 on RTOG 94-10, a phase III trial showing a survival benefit for concurrent chemoradiation (STD RT) over sequential (RT day 50) chemoradiation in LA-NSCLC with intermediate outcome for concurrent twice daily radiation and chemotherapy (HFX RT). 26-month expected costs for each arm of the trial in 1996 dollars were determined, with Kaplan Meier sampling average estimates of survival probabilities for each month and mean monthly costs. The analysis was performed from a payer’s perspective. Incremental cost-effectiveness ratios were calculated comparing RT on day 50 and HFX RT to the STD RT. RESULTS: Of the 610 patients entered, Medicare cost data and clinical outcomes were available for 92 patients. In this subset, compared to STD RT, RT on day 50 proved less costly but resulted in reduced survival at 1 year. In addition, HFX RT cost slightly more than STD RT but was less effective in this cohort of patients. CONCLUSIONS: In patients with Medicare insurance and with significant toxicity burden, RT on day 50 is the least expensive but also least effective treatment in this subset of patients treated on RTOG 94-10.

BACKGROUND: NRG CC001, a phase III trial of WBRT+memantine (WBRT+M) with or without Hippocampal Avoidance (HA), sought to assess the neuro-protective effects of lowering the radiation dose received by the hippocampus. METHODS: Patients (pts) with brain metastases were stratified by RPA class and prior radiosurgery/surgery and randomized to either WBRT+M or HA-WBRT+M (30Gy/10 fractions). Standardized neurocognitive function (NCF) tests were performed at baseline, 2, 4, 6, and 12 months (mos.). The primary endpoint was NCF failure, defined as decline using the reliable change index on Hopkins Verbal Learning Test-Revised, Trail Making Test, or Controlled Oral Word Association. Cumulative incidence estimated NCF failure (death without NCF failure was competing risk); between-arms differences tested using Gray’s test. Deterioration at each collection time point was tested using a chi-square test. Patient-reported symptoms were assessed using the MD Anderson Symptom Inventory with Brain Tumor module and analyzed using mixed effects models and t-tests. RESULTS: From 7/2016 to 3/2018, 518 patients were randomized. Median follow-up was 7.9 mos. HA-WBRT+M was associated with lower NCF failure risk (adjusted HR=0.74, p=0.02) due to lower risk of deterioration in executive function at 4 mos. (p=0.01); and encoding (p=0.049) and consolidation (p=0.02) at 6 mos. Age≤61 predicted for lower NCF failure risk (HR=0.60, p=0.0002); non-significant test for interaction indicated independent effects of HA and age. Patient-reported fatigue (p=0.036); difficulty speaking (p=0.049); and problems remembering things (p=0.013) at 6 mos. favored the HA-WBRT+M arm. Imputation models accounting for missing data also favored the HA-WBRT+M arm for patient-reported cognition (p=0.011) and symptom interference (p=0.008) at 6 mos. Treatment arms did not significantly differ in toxicity; intracranial progression or overall survival. CONCLUSIONS: While achieving similar intracranial control and survival; Hippocampal Avoidance during WBRT+M for brain metastases better preserves NCF and patient-reported symptoms. Supported by UG1CA189867 (NCORP) and DCP from the NCI.

BACKGROUND. Although tri-modality therapy is an acceptable standard of care in patients with locally advanced esophageal cancer, data regarding patterns of failure is lacking. We report bi-institutional patterns of failure experience treating patients using tri-modality therapy. MATERIALS AND METHODS. We retrospectively reviewed patients who underwent chemoradiation followed by esophagectomy between 2006 and 2011 at two NCI-designated cancer centers. First failure sites were categorized as local, regional nodal, or distant. Statistical analysis was performed using Fisher’s exact test, non-parametric Wilcoxon rank-sum test, and multiple logistic regression. Kaplan-Meier curves were generated for relapse-free survival (RFS) and overall survival. RESULTS. A total of 132 patients met the inclusion criteria with a median age of 62 (range 36–80) and median follow-up of 28 months (range 4–128). There were a total of six (4.5%) local, 13 (10%) regional nodal, and 32 (23.5%) distant failures. Local failure was correlated with fewer lymph nodes (LN) assessed (p = 0.01) and close/positive margins (p13 LN evaluated (p = 0.003). Distant recurrence was correlated with higher pathologic nodal stage (p

Purpose Hippocampal neural stem-cell injury during whole-brain radiotherapy (WBRT) may play a role in memory decline. Intensity-modulated radiotherapy can be used to avoid conformally the hippocampal neural stem-cell compartment during WBRT (HA-WBRT). RTOG 0933 was a single-arm phase II study of HA-WBRT for brain metastases with prespecified comparison with a historical control of patients treated with WBRT without hippocampal avoidance. Patients and Methods Eligible adult patients with brain metastases received HA-WBRT to 30 Gy in 10 fractions. Standardized cognitive function and quality-of-life (QOL) assessments were performed at baseline and 2, 4, and 6 months. The primary end point was the Hopkins Verbal Learning Test–Revised Delayed Recall (HVLT-R DR) at 4 months. The historical control demonstrated a 30% mean relative decline in HVLT-R DR from baseline to 4 months. To detect a mean relative decline ≤ 15% in HVLT-R DR after HA-WBRT, 51 analyzable patients were required to ensure 80% statistical power with α = 0.05. Results Of 113 patients accrued from March 2011 through November 2012, 42 patients were analyzable at 4 months. Mean relative decline in HVLT-R DR from baseline to 4 months was 7.0% (95% CI, −4.7% to 18.7%), significantly lower in comparison with the historical control (P < .001). No decline in QOL scores was observed. Two grade 3 toxicities and no grade 4 to 5 toxicities were reported. Median survival was 6.8 months. Conclusion Conformal avoidance of the hippocampus during WBRT is associated with preservation of memory and QOL as compared with historical series.

Purpose Combining cisplatin or cetuximab with radiation improves overall survival (OS) of patients with stage III or IV head and neck carcinoma (HNC). Cetuximab plus platinum regimens also increase OS in metastatic HNC. The Radiation Therapy Oncology Group launched a phase III trial to test the hypothesis that adding cetuximab to the radiation-cisplatin platform improves progression-free survival (PFS). Patients and Methods Eligible patients with stage III or IV HNC were randomly assigned to receive radiation and cisplatin without (arm A) or with (arm B) cetuximab. Acute and late reactions were scored using Common Terminology Criteria for Adverse Events (version 3). Outcomes were correlated with patient and tumor features and markers. Results Of 891 analyzed patients, 630 were alive at analysis (median follow-up, 3.8 years). Cetuximab plus cisplatin-radiation, versus cisplatin-radiation alone, resulted in more frequent interruptions in radiation therapy (26.9% v 15.1%, respectively); similar cisplatin delivery (mean, 185.7 mg/m2 v 191.1 mg/m2, respectively); and more grade 3 to 4 radiation mucositis (43.2% v 33.3%, respectively), rash, fatigue, anorexia, and hypokalemia, but not more late toxicity. No differences were found between arms A and B in 30-day mortality (1.8% v 2.0%, respectively; P = .81), 3-year PFS (61.2% v 58.9%, respectively; P = .76), 3-year OS (72.9% v 75.8%, respectively; P = .32), locoregional failure (19.9% v 25.9%, respectively; P = .97), or distant metastasis (13.0% v 9.7%, respectively; P = .08). Patients with p16-positive oropharyngeal carcinoma (OPC), compared with patients with p16-negative OPC, had better 3-year probability of PFS (72.8% v 49.2%, respectively; P < .001) and OS (85.6% v 60.1%, respectively; P < .001), but tumor epidermal growth factor receptor (EGFR) expression did not distinguish outcome. Conclusion Adding cetuximab to radiation-cisplatin did not improve outcome and hence should not be prescribed routinely. PFS and OS were higher in patients with p16-positive OPC, but outcomes did not differ by EGFR expression.

Pancreatic cancer is relatively radioresistant, however, radiotherapy has been shown to provide efficacy in the treatment of local disease. To increase the effectiveness of radiotherapy in pancreatic cancer, radiosensitizing drugs are under development. In this study, we investigated the radiosensitizing activity of the anti-diabetic drug metformin on pancreatic cancer cells in vitro. We demonstrated that metformin radiosensitized MiaPaCa-2 and Panc1 cells with radiation enhancement ratios (ER) ranging from 1.33–1.45 with metformin concentrations of 30–100 lM ,a nd in addition, we showed that metformin sensitized cells to gemcitabine alone or in combination with radiation treatment. In addition, we found that pancreatic cancer stem celllike cells showed enhanced radiosensitization in a tumorsphere assay with a REF of 1.66. At these radiosensitizing doses, metformin alone had low toxicity (as shown by .75% clonogenic survival) and did not affect cell cycle. The combination of metformin and radiation yielded greater numbers of c-H2AX foci after 1 h compared to radiation alone, suggesting increased DNA damage signaling. Examination of the AMPK pathway showed that pharmacological inhibition of AMPK signaling or RNAi of AMPKa1 reversed metformin-mediated radiosensitization. These studies show that metformin radiosensitization of pancreatic cancer cells at micromolar concentration acts through AMPK and may affect DNA damage signaling. The data indicate that metformin may increase the efficacy of radiation therapy for pancreatic cancer. 2014 by Radiation Research Society

Purpose To determine if escalated radiation dose using hypofractionation significantly reduces biochemical and/or clinical disease failure (BCDF) in men treated primarily for prostate cancer. Patients and Methods Between June 2002 and May 2006, men with favorable- to high-risk prostate cancer were randomly allocated to receive 76 Gy in 38 fractions at 2.0 Gy per fraction (conventional fractionation intensity-modulated radiation therapy [CIMRT]) versus 70.2 Gy in 26 fractions at 2.7 Gy per fraction (hypofractionated IMRT [HIMRT]); the latter was estimated to be equivalent to 84.4 Gy in 2.0 Gy fractions. High-risk patients received long-term androgen deprivation therapy (ADT), and some intermediate-risk patients received short-term ADT. The primary end point was the cumulative incidence of BCDF. Secondarily, toxicity was assessed. Results There were 303 assessable patients with a median follow-up of 68.4 months. No significant differences were seen between the treatment arms in terms of the distribution of patients by clinicopathologic or treatment-related (ADT use and length) factors. The 5-year rates of BCDF were 21.4% (95% CI, 14.8% to 28.7%) for CIMRT and 23.3% (95% CI, 16.4% to 31.0%) for HIMRT (P = .745). There were no statistically significant differences in late toxicity between the arms; however, in subgroup analysis, patients with compromised urinary function before enrollment had significantly worse urinary function after HIMRT. Conclusion The hypofractionation regimen did not result in a significant reduction in BCDF; however, it is delivered in 2.5 fewer weeks. Men with compromised urinary function before treatment may not be ideal candidates for this approach.

Introduction: Radiation-induced pneumonitis and fibrosis have restricted radiotherapy for lung cancer. In a preclinical lung tumor model, soy isoflavones showed the potential to enhance radiation damage in tumor nodules and simultaneously protect normal lung from radiation injury. We have further dissected the role of soy iso- flavones in the radioprotection of lung tissue. Methods: Naive Balb/c mice were treated with oral soy isoflavones for 3 days before and up to 4 months after radiation. Radiation was administered to the left lung at 12 Gy. Mice were monitored for toxic- ity and breathing rates at 2, 3, and 4 months after radiation. Lung tis- sues were processed for histology for in situ evaluation of response. Results: Radiation caused damage to normal hair follicles, leading to hair loss in the irradiated left thoracic area. Supplementation with soy isoflavones protected mice against radiation-induced skin injury and hair loss. Lung irradiation also caused an increase in mouse breathing rate that was more pronounced by 4 months after radia- tion, probably because of the late effects of radiation-induced injury to normal lung tissue. However, this effect was mitigated by soy isoflavones. Histological examination of irradiated lungs revealed a chronic inflammatory infiltration involving alveoli and bronchioles and a progressive increase in fibrosis. These adverse effects of radia- tion were alleviated by soy isoflavones. Conclusion: Soy isoflavones given pre- and postradiation protected the lungs against adverse effects of radiation including skin injury, hair loss, increased breathing rates, inflammation, pneumonitis and fibrosis, providing evidence for a radioprotective effect of soy.

This study seeks to compare fixed-field intensity-modulated radiation therapy (FF IMRT), RapidArc (RA), and helical tomotherapy (HT) to discover the optimal treatment modality to deliver SBRT to the peripheral lung. Eight patients with peripheral primary lung cancer were reviewed. Plans were prescribed a dose of 48 Gy and optimized similarly with heterogeneity corrections. Plan quality was assessed using conformality index (CI100%), homogeneity index (HI), the ratio of the 50% isodose volume to PTV (R50%) to assess intermediate dose spillage, and normal tissue constraints. Delivery efficiency was evaluated using treatment time and MUs. Dosimetric accuracy was assessed using gamma index (3% dose difference, 3 mm DTA, 10% threshold), and measured with a PTW ARRAY seven29 and OCTAVIUS phantom. CI100%, HI, and R50% were lowest for HT compared to seven-field coplanar IMRT and two-arc coplanar RA (plt; 0.05). Normal tissue constraints were met for all modalities, except maximum rib dose due to close proximity to the PTV. RA reduced delivery time by 60% compared to HT, and 40% when compared to FF IMRT. RA also reduced the mean MUs by 77% when compared to HT, and by 22% compared to FF IMRT. All modalities can be delivered accurately, with mean QA pass rates over 97%. For peripheral lung SBRT treatments, HT performed better dosimetrically, reducing maximum rib dose, as well as improving dose conformity and uniformity. RA and FF IMRT plan quality was equivalent to HT for patients with minimal or no overlap of the PTV with the chest wall, but was reduced for patients with a larger overlap. RA and IMRT were equivalent, but the reduced treatment times of RA make it a more efficient modality.

Download Free Sample Are stem cells patentable? What is the patenting process? What rights does a patent provide? Why should I patent? Applying for and obtaining a patent is a process that can be unpredictable and intimidating, although it does not necessarily need to be. Novice and experienced inventors often have questions regarding patenting and the patenting process. This e-book is provided to answer many questions regarding the patenting process before the United States Patent and Trademark Office (“USPTO”). It also generally describes the technologies typically patented in connection with regenerative medicine. This e-book is provided for informational purposes only and should not replace legal advice, which is necessary to anticipate and address the nuances of the patenting process. In addition, there are issues that should be considered and addressed when considering patenting isolated stem cells and associated technologies—such as the process for obtaining patent rights outside the Unite...