IGRT After Prostatectomy: Evaluation of Corrective Shifts and Toxicity Using Online Cone Beam CT vs. Weekly Port Films for Target Localization

Purpose/Objective(s): Image guidance (IG) may permit higher radiotherapy (RT) doses (\u3e65 Gy) after radical prostatectomy (RP) without increased toxicity, with improved accuracy and smaller margins. Conebeam (CBCT) allows IGRT with volumetric images. This study evaluated CBCT shifts and toxicity after conformal IGRT, compared to RT with port films. American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C

Costs of Early Adjuvant Radiation Therapy After Radical Prostatectomy: A Decision Analysis

Purpose/Objective(s): Prospective, randomized trials support adjuvant radiation therapy (RT) for adverse pathologic features after radical prostatectomy (RP). However, adjuvant RT is not universally delivered in this setting. Criticisms of adjuvant RT include toxicity, financial costs, potential overtreatment, and effectiveness of salvage RT. The objective of this study was to construct a decision analytic model to estimate real world cost of RT vs. no RT within the context of the effectiveness of early adjuvant RT for prostate patients based on published clinical results of the Southwest Oncology Group prospective trial of adjuvant RT (SWOG 8794). American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C

Identifying barriers to patient acceptance of active surveillance: content analysis of online patient communications.

OBJECTIVES: Qualitative research aimed at identifying patient acceptance of active surveillance (AS) has been identified as a public health research priority. The primary objective of this study was to determine if analysis of a large-sample of anonymous internet conversations (ICs) could be utilized to identify unmet public needs regarding AS. METHODS: English-language ICs regarding prostate cancer (PC) treatment with AS from 2002-12 were identified using a novel internet search methodology. Web spiders were developed to mine, aggregate, and analyze content from the world-wide-web for ICs centered on AS. Collection of ICs was not restricted to any specific geographic region of origin. NLP was used to evaluate content and perform a sentiment analysis. Conversations were scored as positive, negative, or neutral. A sentiment index (SI) was subsequently calculated according to the following formula to compare temporal trends in public sentiment towards AS: [(# Positive IC/#Total IC)-(#Negative IC/#Total IC) x 100]. RESULTS: A total of 464 ICs were identified. Sentiment increased from -13 to +2 over the study period. The increase sentiment has been driven by increased patient emphasis on quality-of-life factors and endorsement of AS by national medical organizations. Unmet needs identified in these ICs include: a gap between quantitative data regarding long-term outcomes with AS vs. conventional treatments, desire for treatment information from an unbiased specialist, and absence of public role models managed with AS. CONCLUSIONS: This study demonstrates the potential utility of online patient communications to provide insight into patient preferences and decision-making. Based on our findings, we recommend that multidisciplinary clinics consider including an unbiased specialist to present treatment options and that future decision tools for AS include quantitative data regarding outcomes after AS

PARP-1 regulates DNA repair factor availability.

PARP-1 holds major functions on chromatin, DNA damage repair and transcriptional regulation, both of which are relevant in the context of cancer. Here, unbiased transcriptional profiling revealed the downstream transcriptional profile of PARP-1 enzymatic activity. Further investigation of the PARP-1-regulated transcriptome and secondary strategies for assessing PARP-1 activity in patient tissues revealed that PARP-1 activity was unexpectedly enriched as a function of disease progression and was associated with poor outcome independent of DNA double-strand breaks, suggesting that enhanced PARP-1 activity may promote aggressive phenotypes. Mechanistic investigation revealed that active PARP-1 served to enhance E2F1 transcription factor activity, and specifically promoted E2F1-mediated induction of DNA repair factors involved in homologous recombination (HR). Conversely, PARP-1 inhibition reduced HR factor availability and thus acted to induce or enhance BRCA-ness . These observations bring new understanding of PARP-1 function in cancer and have significant ramifications on predicting PARP-1 inhibitor function in the clinical setting

Potential for Dose-escalation in the Post-prostatectomy Setting with Intensitymodulated Radiation Therapy: A Dosimetric Study Using EORTC Consensus Guidelines for Target Volume Contours

Purpose: Radiation therapy (RT) is delivered after radical prostatectomy (RP) for prostate cancer (PC). Although intensity modulated radiation therapy (IMRT) has become standard in definitive RT for PC, dosimetric data in support of post-RP IMRT are limited. This study was designed to quantify benefits of IMRT versus 3D conformal RT (3DCRT) with respect to dose sparing of rectum and bladder and target volume coverage. Motivated by the desire to deliver higher radiation doses and to quantify the dosimetric impact of IMRT, we retrospectively analyzed images in order to: 1) identify a preferred IMRT beam arrangement; 2) evaluate the dosimetric advantages of IMRT compared to 3DCRT; and 3) assess the variation of dosimetric parameters during the RT course using conebeam CT (CBCT) images. American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C

Atypical Enteropathogenic Escherichia coli Infection and Prolonged Diarrhea in Children

Infection of children with atypical EPEC is associated with prolonged diarrhea