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// Adam R. Wolfe 1 , * , Patrick Wald 1 , * , Amy Webb 1 , Nikhil Sebastian 1 , Steve Walston 1 , Ryan Robb 1 , Wei Chen 1 , Marall Vedaie 1 , Mary Dillhoff 1 , Wendy L. Frankel 1 , Wooil Kwon 2 , Jin-Young Jang 2 and Terence M. Williams 1 1 The Ohio State University Medical Center, Arthur G. James Comprehensive Cancer Center and Richard J. Solove Research Institute, Columbus, OH, USA 2 Department of Surgery, Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea * Co-first authors Correspondence to: Terence M. Williams, email: terence.williams@osumc.edu Keywords: pancreatic cancer; miRNA; non-coding RNA; prognostic biomarker; local-regional recurrence Received: November 12, 2019 Accepted: January 29, 2020 Published: March 10, 2020 ABSTRACT Resectable pancreatic adenocarcinoma (PC) is generally managed with surgery followed by chemotherapy, but the role of postoperative chemoradiation (pCRT) is controversial. We sought to identify a microRNA (miRNA) expression profile associated with higher risk for local-regional recurrence (LRR), which might help identify patients that may benefit from pCRT. Total RNA was isolated from viable tumor from 88 patients who underwent PC resection with or without chemotherapy, but did not receive radiation. Digital miRNA expression profiling was performed and risk scores were calculated based on the expression levels of the four most significantly correlated miRNAs, and dichotomized about the median to detect correlations between risk group, LRR and overall survival (OS). Two cohorts from The Cancer Genome Atlas (TCGA) and Seoul National University (SNU) were used for validation. Patients with high-risk scores had significantly worse LRR ( p = 0.001) and worse OS ( p = 0.034). Two-year OS rates for the high- and low-risk groups were 27.7% and 52.2%, respectively. On multivariable analysis, the risk score remained significantly associated with LRR ( p = 0.018). When validated on TCGA data, a high-risk score was associated with worse OS on univariate ( p = 0.03) and multivariable analysis ( p = 0.017). When validated on the SNU cohort, a high-risk score was likewise associated with worse OS ( p = 0.042). We have developed a 4-miRNA molecular signature that is associated with risk of LRR and OS after PC resection and validated on two separate cohorts. This signature has the potential to select patients most likely to benefit from pCRT, and should be tested further.

Background In patients with stage III melanoma, the use of adjuvant radiation therapy (RT) after lymph node dissection (LND) may be currently considered in selected high-risk patients to improve tumor control. Melanomas harbor BRAF mutations (BRAF+) in 40–50% of cases, the majority of which are on the V600E residue. This study sought to compare the clinical outcomes after RT between patients with BRAF+ and BRAF− melanoma. Methods This was a retrospective review of 105 Stage III melanoma patients treated at our institution with LND followed by adjuvant RT from 2006 to 2019. BRAF mutational status was determined on the primary skin or nodal tissue samples from all patients. We compared characteristics of the BRAF+ and BRAF− groups using Fisher’s exact test and Wilcoxon rank sum test and performed univariate and multivariate analysis using Kaplan–Meier estimates, log-rank tests, and Cox proportional hazards modeling with the clinical outcomes of local–regional lymph node control, distant metastasis-free survival (DMFS), recurrence-free survival (RFS), and overall survival (OS). Results Fifty-three (50%) patients harbored a BRAF mutation (92%, pV600E). BRAF+ patients were younger and had primary tumors more commonly found in the trunk vs head and neck compared to BRAF- patients (p BRAF + patients was 60% compared to 81% in the BRAF- patients (HR 4.5, 95% CI 1.3–15.5, p = 0.02). There were no significant differences in 5-year DMFS, RFS, and OS rates between the two BRAF patient groups. The presence of 4 or more positive LNs remained a significant prognostic factor for local–regional lymph node control, RFS, and OS in multivariate analysis. Conclusions Stage III melanoma patients with BRAF mutation treated with adjuvant RT had > 4 times increased risk of local recurrence or regional lymph node recurrence. These results could be useful for adjuvant RT consideration in lymph node positive melanoma patients and supports other data that BRAF mutation confers radiation resistance.

The purpose of this study was to investigate the dosimetric impact of weight loss in head and neck (H&N) patients and examine the effectiveness of adaptive planning. Data was collected from 22 H&N cancer patients who experienced weight loss during their course of radiotherapy. The robustness of Intensity Modulated Radiation Therapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) treatment plans were compared including the potential need for replanning. The dosimetric impact of weight loss was evaluated by calculating a verification plan for each patient on an assessment CT scan taken during the course of treatment. Using a regression analysis, significance was tested for the dosimetric change in target volumes and 10 specific organs at risk (OAR) using an anatomical separation difference in the H&N at corresponding levels. For both the IMRT and VMAT plans, a significant correlation was found for the dose to 5% of the high risk Planning Target Volume (PTV) (D5), dose to 95% of the intermediate risk PTV and Clinical Target Volume (CTV) (D95), and the percentage of the pharynx receiving 65 Gy. An independent t-test was also performed for each metric in the VMAT and IMRT plans showing the dose to 95% of the intermediate risk PTV as significant. No quantitative method for finding the threshold of anatomical separation difference requiring a replan was established. Based on the increase in dose to organs at risk and increased target coverage due to separation loss, it was concluded that adaptive radiotherapy may not always be necessary when alignment of bony anatomy and remaining soft tissue is within tolerance. Physician judgment and preference is needed in such situations.

Background To report our institutional experience with intraoperative radiotherapy for persistent or recurrent head and neck cancer. Methods Sixty-one patients were treated with salvage surgery and intraoperative radiation therapy (IORT). Fifty-eight patients (95%) had previously received external beam radiotherapy (EBRT) as a component of their definitive therapy. Forty-four patients (72%) had squamous cell carcinoma (SCC). Surgical margins were positive in 28 patients (46%). IORT was prescribed to a median dose of 12.5 Gy (range, 10-17.5). Twenty-three patients (38%) received a course of postoperative EBRT (median 45 Gy). Clinical outcomes were retrospectively reviewed and univariate analysis was performed using log-rank tests to correlate clinical outcomes with histology, surgical margin, and adjuvant therapy. Results Median follow-up among surviving patients was 15.9 months. Median progression-free survival (PFS) and overall survival (OS) were 9.8 and 19.1 months, respectively. One- and 2-year rates of locoregional control (LRC) were 59% and 35%, respectively. One- and 2-year rates of PFS were 39% and 19%, respectively. One- and 2-year rates of OS were 62% and 42%, respectively. Overall survival was better for non-SCC histology (P = .03). For SCC patients, negative surgical margin showed a trend toward improved PFS (P = .09) and OS (P = .06). There was one grade-5 toxicity due to carotid rupture. Conclusions IORT has shown effective LRC and OS with an acceptably low rate of severe toxicity at our institution. OS was significantly better for non-SCC histology. For SCC patients, there is a trend toward improved PFS and OS associated with negative surgical margins.

OBJECTIVES: The role of radiation therapy (RT) in resected pancreatic cancer (PC) remains incompletely defined. We sought to determine clinical variables which predict for local-regional recurrence to help select patients for adjuvant RT. METHODS: We identified 73 patients with PC who underwent resection and adjuvant gemcitabine-based chemotherapy alone. We performed detailed radiologic analysis of first patterns of failure. Local-regional recurrence was defined as recurrence of PC within standard post-operative radiation volumes. Univariate analyses (UVA) were conducted using the Kaplan-Meier method and multivariate analyses (MVA) utilized the Cox proportional hazard ratio model. Factors significant on UVA were used for MVA. RESULTS: At median follow up of 20 months, rates of local-regional recurrence only (LRRO) were 24.7%, local-regional recurrence as a component of any failure (LRR) 68.5%, metastatic recurrence as a component of any failure (MR) 65.8%, and overall disease recurrence (OR) 90.5%. On UVA, elevated post-operative CA 19-9 (>90 U/mL), pathological lymph node positive (pLN+) disease, and higher tumor grade were associated with increased LRR, MR, and OR. On MVA, elevated post-operative CA 19-9 and pLN+ were associated with increased MR and OR. Additionally, positive resection margin was associated with increased LRRO on both UVA and MVA. CONCLUSIONS: About 25% of patients with PC treated without adjuvant RT develop LRRO as initial failure. The only independent predictor of LRRO was positive margin, while elevated post-operative CA 19-9 and pLN+ were associated with predicting MR and OS. These data may help determine which patients benefit from intensification of local therapy with radiation.

// Cory Pettit 1 , Amy Webb 1 , Steve Walston 1 , Moumita Chatterjee 1 , Wei Chen 1 , Wendy Frankel 1 , Carlo Croce 1 and Terence M. Williams 1 1 The Ohio State University Medical Center, Arthur G. James Comprehensive Cancer Center and Richard J. Solove Research Institute, Columbus, OH 43210, USA Correspondence to: Terence M. Williams, email: terence.williams@osumc.edu Keywords: miRNA; rectal cancer; chemotherapy; radiation; biomarker Received: February 05, 2018 Accepted: April 02, 2018 Published: June 22, 2018 ABSTRACT Purpose: There has been growing interest in using chemoradiation (CRT) for non-operative management of rectal cancer, and identifying patients who might benefit most from this approach is crucial. This study identified miRNAs (miRs) associated with clinical outcomes and treatment resistance by evaluating both pre- and post-CRT expression profiles. Methods: Forty patients, 9 with pathologic complete response (pCR) and 31 with pathologic incomplete response (pIR) were included. MicroRNA was extracted from 40 pre-therapy tumor samples and 31 post-chemoradiation surgical samples with pathologic incomplete response (pIR). A generalized linear model was used to identify miRs associated with pCR. A linear mixed effects model was used to identify miRs differentially expressed before and after treatment. miR expression was dichotomized at the mean and clinical outcomes were evaluated using Cox proportional hazard modeling. Results: Nine miRs were associated with pCR (p

The benefit of adjuvant chemotherapy in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (nCRT) and surgery is controversial. We examined the association of perineural invasion (PNI) with outcomes to determine whether PNI could be used to risk-stratify patients. We performed a retrospective study of 110 patients treated with nCRT and surgery for LARC at our institution from 2004 to 2011. Eighty-seven patients were identified in our final analysis. We evaluated the association of PNI with locoregional control, distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival, using log-rank and Cox proportional hazard modeling. Fourteen patients (16%) were PNI+ and 73 patients (84%) were PNI−. The median follow-up was 27 months (range, 0.9 to 84 mo). The median DMFS was 13.5 months for PNI+ and median not reached (>40 mo) for PNI− (P

Purpose: To present our clinical workflow of incorporating AlignRT for left breast deep inspiration breath-hold treatments and the dosimetric considerations with the deep inspiration breath-hold protocol. Material and Methods: Patients with stage I to III left-sided breast cancer who underwent lumpectomy or mastectomy were considered candidates for deep inspiration breath-hold technique for their external beam radiation therapy. Treatment plans were created on both free-breathing and deep inspiration breath-hold computed tomography for each patient to determine whether deep inspiration breath-hold was beneficial based on dosimetric comparison. The AlignRT system was used for patient setup and monitoring. Dosimetric measurements and their correlation with chest wall excursion and increase in left lung volume were studied for free-breathing and deep inspiration breath-hold plans. Results: Deep inspiration breath-hold plans had significantly increased chest wall excursion when compared with free breathing. This change in geometry resulted in reduced mean and maximum heart dose but did not impact lung V20 or mean dose. The correlation between chest wall excursion and absolute reduction in heart or lung dose was found to be nonsignificant, but correlation between left lung volume and heart dose showed a linear association. It was also identified that higher levels of chest wall excursion may paradoxically increase heart or lung dose. Conclusion: Reduction in heart dose can be achieved for many left-sided breast and chest wall patients using deep inspiration breath-hold. Chest wall excursion as well as left lung volume did not correlate with reduction in heart dose, and it remains to be determined what metric will provide the most optimal and reliable dosimetric advantage.

Randomized trials evaluating cisplatin versus cetuximab chemoradiation (CRT) for p16+ oropharyngeal cancer (OPC) have yet to report preliminary data. Meanwhile, as a preemptive step toward morbidity reduction, the off-trial use of cetuximab in p16+ patients is increasing, even in those who could potentially tolerate cisplatin. The purpose of this study was to compare the efficacy of cisplatin versus cetuximab CRT in the treatment of p16+ OPC and to identify prognostic factors and predictors of tumor response.Cases of p16+ OPC treated with cisplatin or cetuximab CRT at our institution from 2010 to 2014 were identified. Recursive partitioning analysis (RPA) classification was used to determine low-risk (LR-RPA) and intermediate-risk (IR-RPA) groups. Log-rank/Kaplan-Meier and Cox Regression methods were used to compare groups.We identified 205 patients who received cisplatin (n = 137) or cetuximab (n = 68) CRT in the definitive (n = 178) or postoperative (n = 27) setting. Median follow-up was 3 years. Cisplatin improved 3-year locoregional control (LRC) [92.7 vs 65.4%], distant metastasis-free survival (DMFS) [88.3 vs 71.2%], recurrence-free survival (RFS) [86.6 vs 50.6%], and overall survival (OS) [92.6 vs 72.2%] compared to cetuximab [all p .001]. Concurrent cisplatin improved 3-year OS for LR-RPA (97.1 vs 80.3%, p .001) and IR-RPA (97.1 vs 80.3%, p .001) groupings.When treating p16+ OPC with CRT, the threshold for substitution of cisplatin with cetuximab should be maintained appropriately high in order to prolong survival times and optimize locoregional and distant tumor control. When cetuximab is used in cisplatin-ineligible patients, altered fractionation RT should be considered in an effort to improve LRC.

Treatment for locally-advanced rectal cancer (LARC) typically consists of neoadjuvant chemoradiation followed by total mesorectal excision. Recently, there has been growing interest in non-operative management for patients who are medically-inoperable or wish to avoid surgical morbidity and permanent colostomy. Approximately 50% of patients who receive pre-operative neoadjuvant chemoradiation develop some degree of pathologic response. Approximately 10-20% of patients are found to have a complete pathologic response, a finding which has frequently been shown to predict better clinical outcomes, including local-regional control, distant metastasis and survival. Many recent studies have evaluated the role of molecular biomarkers in predicting response to neoadjuvant therapy. MicroRNAs (miRNAs) are an emerging class of biomarkers that have the potential to predict which patients are most likely to benefit from pre-operative therapy and from a selective surgical approach. Here, we review the published literature on microRNAs as prognostic and predictive biomarkers in rectal cancer after pre-operative therapy. In the future, the development of prospectively validated miRNA signatures will allow clinical implementation of miRNAs as prognostic and predictive signatures in LARC.

Intracranial tumors, both primary and metastatic, have distinct anatomic and neuroimaging features. Radiotherapy is often used in the management of intracranial tumors. Various techniques used in radiotherapy include external beam radiotherapy and stereotactic radiotherapy. This chapter discusses the use of neuroimaging in tumor delineation and radiation planning and delivery. Evaluation of immobilization, target volumes, normal tissue volumes, plan review, and quality assurance is required to safely deliver radiotherapy. The practical review of radiotherapy in high-grade glioma is used to demonstrate these facets of patient care. Neuroimaging and clinical evaluation are used to evaluate for disease recurrence following treatment completion. On standard magnetic resonance imaging, it may be difficult to differentiate between pseudo-progression, true disease progression, and radiation necrosis. A multitude of imaging techniques are now available to assist in making this distinction. The progress in neuroimaging has improved radiation planning and delivery and will continue to do so in the future.

Introduction Pediatric high grade gliomas are rare tumors with poor outcomes and incompletely defined management. We conducted a multi-institutional retrospective study to evaluate association of clinical, pathologic, and treatment characteristics with outcomes.Materials and methodsFifty-one patients treated from 1984-2008 at Ohio State University or University of Michigan were included. Histologic subgroups were compared. Log-rank and stepwise Cox proportional hazard modeling were used to analyze progression-free survival (PFS) and overall survival (OS) within the whole group, grade III subgroup, grade IV subgroup, and subtotal resection/biopsy subgroup. ResultsMedian OS was 27.6 months. Grade III histology, complete tumor resection, and cerebral tumor location correlated with improved PFS and OS. Temozolomide use and chemotherapy after radiotherapy or chemoradiation were associated with better PFS while seizure at presentation was associated with better OS. In multivariate analysis, complete resection and chemotherapy following radiotherapy or chemoradiation were independent predictors for improved PFS and OS. For grade III and IV subgroups, complete resection was associated with improved OS (grade III) and seizure presentation was associated with improved OS (grade IV). In the incompletely resection subgroup, temozolomide use and concurrent chemoradiation independently correlated with improved PFS, while higher radiation dose (≥ 59.4 Gy), and adjuvant chemotherapy were independently associated with improved OS. DiscussionTotal resection and receiving chemotherapy adjuvant to radiation or chemoradiation are most closely associated with improved PFS and OS. For higher risk incompletely-resected patients, temozolomide use and treatment intensification with concurrent chemoradiation, adjuvant chemotherapy, and higher radiation dose were associated with improved outcomes.

Objectives To assess the reliability of applying a radiographic scoring system in estimating the severity of stool retention (SR) in hospitalized older adults with constipation, and to identify risk factors associated with clinical constipation and SR scores. Design Retrospective, case series study. Setting Southeast Ohio community hospital. Participants Adults 65 years or older with constipation or fecal impaction and abdominal radiographs available (N = 122). Bowel obstruction was excluded. Measurement Radiographs were independently scored by four readers twice, “5” being the most severe, for each quadrant of an abdominal film; possible total score was 0 to 20. Clinical constipation was defined as an average SR score of 13 or higher. Intra-class correlation was used to measure inter-rater agreement. Results The overall inter-rater agreement on abdominal radiograph readings was 0.91, 95% confidence interval (CI) = 0.88–0.93. Clinical constipation was associated with the use of statins and antimuscarinics by univariate logistic regression analysis. After adjusting for age, sex, residency, smoking history, oral laxatives, and self-reported constipation, the use of statins remained significantly associated with clinical constipation (OR = 3.86, 95% CI = 1.08–13.77, P = .036). Univariate linear regression analysis revealed that higher SR scores were associated with community residency, self-reported constipation, and the use of statins and antimuscarinics. After adjusting for the above confounders by multiple linear regression analyses, the use of antimuscarinics was independently associated with higher SR score (β = 1.769, 95% CI = 0.008–3.531, P = .049). Conclusion Abdominal radiography was reliable in assessing the severity of SR in older adults with constipation. The use of statins and antimuscarinics was associated with clinical constipation and greater SR.

750 Background: Perineural invasion (PNI) as a prognostic indicator has not been well studied in patients with rectal adenocarcinoma treated with neoadjuvant chemoradiation (nCRT). In this study, we investigated the incidence and prognostic significance of PNI in patients with stages II-III locally advanced rectal cancer treated with nCRT. Methods: We performed a retrospective study of 110 consecutive patients treated with nCRT for locally advanced rectal adenocarcinoma at a single institution from 2004 to 2011. 88 of these patients had residual tumor in the resected specimen after nCRT. We evaluated the association of PNI with clinical outcomes, including disease-free survival (DFS), distant-metastasis-free survival (DMFS), and overall survival (OS), using log-rank and Cox proportional hazard modeling. Results: Of the 88 patients with residual tumor at surgery, 14 patients (16%) had PNI and 74 patients (84%) did not. Baseline distribution of selected variables in the PNI+ and PNI- groups are shown in Table 1. Median follow-up was 27 months (range 0.9 to 84 months). The median DFS was 13.5 months for PNI+ patients and 39.8 months for PNI- patients (p 40 months) for PNI- patients (p

e19040 Background: Melanoma only accounts for 4% of skin cancer while causing 75% of cancer related deaths. Worldwide incidence is increasing faster than any other cancer, and there are few effective treatment options for invasive disease translating to poor survival. The burgeoning understanding of molecular mechanisms driving carcinogenesis creates unique opportunities to develop targeted therapy. This is especially apparent in the case of BRAF in melanoma. BRAF V600E mutations occur in up to 50% of melanomas endowing these tumors with a constitutively activated MAPK pathway. Blockade of BRAF mutated tumors shows impressive initial responses above 80%. However, single-agent targeted therapy is often plagued with an emergence of resistant clones, and these impressive responses were transient. Diverse resistance mechanisms have been reported at the transcriptome level in patients treated with BRAF inhibitors. However, reports elucidating the prominent epigenetic regulators of resistance to BRAF inhibition are lacking. Methods: We sequenced the DNA of 14 melanoma cell lines and determined 9 had BRAF V600E mutation and 5 were wild type. We also sequenced cancer genes such as p53, PTEN, cKit, NRAS, etc. The BRAF mutant cells were exposed to PLX4032 (BRAF V600E inhibitor) and the concentrations were incrementally increased to develop resistant clones. This resistance was corroborated using annexin V / PI assay to display approximately a 50% decrease in apoptosis in drug resistant cells compared with control cells after 5 days of 5 µM PLX4032 exposure. The epigenome was profiled in control and resistance clones. Results: The statistically significant clusters were identified and currently we are validating their relevance using functional models. We are also profiling the epigene expression levels in melanoma patient biopsies to determine their predictive and prognostic value. Conclusions: It is likely the epigenome plays an integral role in the previously demonstrated mechanisms of BRAF resistance. Our study should illuminate connections with pathways conveying drug resistance to increase understanding of these mechanisms. Consequently, it may be possible to develop improved treatments and prognostic biomarkers.

Purpose: Glioblastoma (GBM) is the most aggressive form of glioma. With average patient survival of about 14 months, largely due to its resistance to conventional therapies, there is opportunity for significant improvements to care. Nicotinamide-N-methyltransferase (NNMT) is an enzyme responsible for the methylation of Nicotinamide and other xenobiotic compounds. Although NNMT's exact role in the malignant phenotype remains poorly understood, it has been investigated for its potential use as a prognostic marker or therapeutic target in other cancers. It is detected at very low levels in normal brain tissue but at significantly higher levels in GBM. Additionally, Kaplan-Meier plots from publically available data sets suggest that higher NNMT expression is correlated with adverse patient outcome. In addition to gene interference and various functional assays, we employed a targeted metabolomic approach, using LC-MS Quadropole Time of Flight (Q-TOF) and LC-MS Triple Quad (QQQ) instruments to study intracellular levels of Nicotinamide and N-methylnicotinamide to gain a better understanding of NNMT's role in GBM. Methods: We determined the expression profile of NNMT in established (ATCC) and in our panel of patient derived, primary GBM cell lines. By generating an NNMT isogenic model in U87 cells, we were able to study the functional consequences of differential NNMT expression using in vitro assays such as MTS Assay, Clonogenic Survival Assay, Annexin V, ATP Assay, Comet Assay, and Western Blotting. We intracranially injected NOD-SCID mice with U87 NNMT cells to assess differences in tumorgenicity in vivo. We have also used LC-MS Quadropole Time of Flight (Q-TOF) and LC-MS Triple Quad (QQQ) instruments to measure intracellular levels of the metabolites relevant to NNMT enzymatic function. Results and Conclusions: Results indicate that NNMT protein is highly expressed in primary cell lines. Encouragingly, U87 NNMT Knockdown cells are less proliferative, more sensitive to radiation in vitro, and are less tumorgenic in vivo. Recapitulating the clinical observations, these results could justify why clinically patients with lower expression of NNMT enjoyed increased overall survival. These results also suggest that finding ways to decrease NNMT in patient's tumors may improve response to radiation. Additional preliminary results indicate that intracellular N-methylnicotinamide levels correlate directly with NNMT protein expression and could be used a surrogate biomarker for intracellular NNMT levels, potentially predicting not only overall survival but perhaps response to radiation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-6. doi:1538-7445.AM2012-LB-6

Purpose: Melanoma only accounts for 4% of skin cancer while causing 75% of cancer related deaths. Also, the incidence is increasing with the annual percent change in the United States reported as 2.4% for the period 1986-2006 and currently increasing faster than any other cancer worldwide. Moreover, patients who develop locally advanced or metastatic melanoma have limited treatment options with 5-year survival rates of 65% and 16%, for regional disease and metastatic disease, respectively. Historically, melanoma was regarded as resistant to radiation therapy (RT), however, recently the utility of RT has been re-explored in the adjuvant setting with fractionated radiotherapy (FRT) and also in the oligometastatic setting with stereotactic radiotherapy (SBRT), and does show increase in local control in appropriately selected patients. The importance of microRNA (miRNA) in cancer continues to be elucidated and in melanoma they are extensively reported as having significant roles in melanoma transformation, progression, invasiveness, metastasis, and outcome/prognosis. However, there are no reports of melanoma miRNA profiling and RT. miRNA expression profiles change as a consequence of RT in several tumor types. Experiments show delivery of miRNA in vivo appears both feasible and tolerable in murine models. Additionally, correcting miRNA deregulation has been shown to mitigate the tumorigenic phenotype and also induce radiosensitivity in vitro and in vivo. Materials/Methods: We cultured more than a dozen melanoma cell lines and sequenced for mutations in key genes such as B-RAF, N-RAS, etc. to group them. Next we isolated their miRNA of untreated and treated with 6 Gray dose of radiation isolated at 5 days. The miRNA expression was quantified using RT-qPCR of TaqMan Low Density Arrays (TLDA) cards. The data is reported using hierarchical clustering and those miRNAs significantly deregulated have been delineated. Results/Discussion: We have characterized the miRNA expression profiles of melanoma cell lines when comparing untreated and those treated with radiation. Our data indicate that miRNA profiles done pre and post RT are significantly different. To this end we have identified clusters of miRNA associated with RT sensitivity/resistance. Thus, these miRNAs could be important factors in response to RT and their differential expression may be linked to resistance to RT. Consequently, it is conceivable that these miRNA and/or their mRNA targets could be used in the future as targets for drug development to radiosensitize melanoma and thus further improve outcomes. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5052. doi:1538-7445.AM2012-5052

Purpose/Objectives: Historically, melanoma has been considered a relatively radioresistant tumor. Newer data have challenged this viewpoint, and radiation therapy (RT) is now considered to be useful for treating patients with malignant melanoma. Most importantly, it can provide effective palliation for the 40 to 50 percent of patients who develop unresectable locally recurrent or metastatic disease producing bone pain, epidural spinal cord compression, central nervous system dysfunction due to brain involvement, and/or tumor hemorrhage. RT has also been applied after complete excision of a primary melanoma or after therapeutic lymphadenectomy for regional nodal disease as adjuvant therapy to reduce the rate of local recurrence for certain types of melanoma. Melanoma is the most lethal form of skin cancer and incidences in the United States have steadily increased over the past 30 years. According to the American Cancer Society, melanoma accounts for only 3 percent of all skin cancers, but is responsible for nearly 74 percent of the deaths resulting from skin cancer. Prognosis is particularly poor for patients with metastasis as only 15 percent of this patient population survives for more than 5 years. Melanoma has been regarded as resistant to most treatments including radiation therapy. Melanoma has been poorly studied from the perspective of radiation biology and it is our intentions to elucidate key molecular mechanisms that can improve the benefit of radiotherapy in melanoma. Materials/Methods: In this study we set out to study genes that are commonly mutated in melanoma: BRAF, N-RAS, CKIT, TP53, PTEN, etc. These genes were sequenced in our panel of melanoma cell lines for determination of mutational status. We then stratified the cell lines based on their response to radiation as measured in a clonogenic survival and other functional assays. Established (ATCC) and primary (OSUMC patients) cell lines were used in this study. From the radioresistant melanoma cell lines we were able to isolate a small subpopulation of cells which exhibited the properties of stem cells and currently we are conducting further studies to completely characterize this sub population. Results/Conclusion: Melanoma has been poorly studied from the perspective of radiation biology and it is our intentions to elucidate key molecular mechanisms that can improve the benefit of radiotherapy in melanoma. It appears that BRAF intact cell lines are radiosensitive, whereas a mutation in at least one of the BRAF alleles at codon 600 leads to a radioresistant phenotype. We have adapted a pathway based targeting approach rather than the conventional gene based methods. We will present our preclinical studies on how genetic and molecular signatures in melanoma play a pivotal role in radiosensitizing melanoma and which subset of melanoma patients would derive the benefit from RT. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2504. doi:10.1158/1538-7445.AM2011-2504

Context: Information is limited in the stool retention (SR) and distribution patterns of constipated older adults. Objective: By using a radiographic scoring system for assessing the severity of SR in hospitalized constipated elderly, we investigate SR distribution patterns between two groups (highvs. low-scored) and to identify factors associated with high and low SR scores. Method: Adults aged ≥65 years admitted to a community hospital between 2005 and 2008 who were discharged with primary or secondary diagnosis of constipation without bowel obstruction and also had abdominal radiographs during the stay (N=131). Poor quality films (N=9) were excluded. Abdominal radiographs were scored by four readers. A score 0-5 (5 being the most severe) for each quadrant of radiographs (total score: 0-20) was used to estimate the severity of SR. Each quadrant represents the approximate location of ascending (Q1), transverse (Q2), descending (Q3), and recto-sigmoid colon area (Q4). Those with scores ≥ 13 were in the high-scored group (N=71); ≤12 in the low-scored group (N=39). Results: The range of average total SR scores was 7 to 18.9; mean score ±SD, 13.4±2.5. The high-scored group was younger than the low-scored group (mean±SD: 81.4±8.2 vs. 86.8±7.3 years, p