Patrick Kupelian

46 Background: Stereotactic body radiotherapy (SBRT) for high-risk prostate cancer (CaP) remains investigational not only due to undetermined efficacy but also due to concerns for the potential toxicity when the treatment volumes extend beyond the prostate gland itself. Methods: Men with high-risk CaP, as defined by Gleason score > = 8, clinical stage T3-T4, or initial PSA > = 20 ng/mL, were enrolled on a multicenter phase II trial and were treated with 40 Gy to prostate and 25 Gy to pelvic nodes in 5 fractions and 9 months neoadjuvant and concurrent ADT. Treatment with ADT and pelvic nodal radiation was at the discretion of the treating physician. Follow-up assessment was with CTCAE v4 and Expanded Prostate Composite Index (EPIC). Results: A total of 61 patients were treated, with a median follow-up of 12 months. Forty (64.4%) received ADT and 23 (37.1%) received nodal radiation. The median initial PSA was 8.1 ng/mL and 8% of patients had clinical T3-T4 disease; 45.9% and 39.3% had Gleason score 8 and 9-10 disease, respectively. No grade 3 or higher toxicities were seen. Rates of acute and late grade 2 genitourinary toxicities were 13.1% and 6.7%, respectively; rates of acute and late grade 2 gastrointestinal toxicities were 6.6% and 8.2%, respectively. Mean changes in EPIC urinary incontinence, urinary obstructive, and bowel domain scores at 4 months were -0.35, +1.44, and -2.38, respectively. For the 32 patients with evaluable EPIC scores at 12 months, mean changes on EPIC urinary incontinence, urinary obstructive, and bowel domain scores at 4 months were -1.04, -2.70, and -6.76, respectively. The percentages of patients with minimum clinically important change in EPIC urinary incontinence, urinary obstructive, and bowel domain scores at 4 months were 11.9%, 21.4%, and 26.2%, respectively. At 12 months, these figures were 13.9%, 30.6% and 27.8%. The receipt of ADT and/or nodal radiation had no significant effect on either physician- or patient-reported toxicity profiles (p > 0.1, Fisher’s exact test). Conclusions: SBRT regimens can be safely utilized to deliver the entire course in 5 treatment days in patients with high-risk localized CaP. Clinical trial information: NCT02296229.

7 Background: To compare the outcomes of a modern cohort of patients with Gleason Score (GS) 9-10 prostate adenocarcinoma (CaP) following treatment with external beam radiotherapy (EBRT), extremely dose-escalated radiotherapy (as exemplified by EBRT with a brachytherapy boost [EBRT+BT]), and radical prostatectomy (RP). Methods: One-thousand-and-one patients with biopsy GS 9-10 CaP who received definitive treatment between 2000 and 2013 were included (347 treated with EBRT, 330 with EBRT+BT, and 324 with RP). Kaplan-Meier analysis and multivariate Cox regression compared 5- and 10-year rates of distant metastasis-free survival (DMFS), cancer-specific survival (CSS), and overall survival (OS). Prostate cancer-mortality (PCSM) rates were compared with a competing risk analysis. Results: The median followup periods were 4.8, 6.4, and 5.1 years among patients receiving EBRT, EBRT + BT, and RP. The median doses among EBRT and EBRT+BT patients were equivalent to 78 Gy and 90 Gy in 2 Gy fractions. Over 90% of patients treated with EBRT or EBRT+BT received ADT (median durations of 18 months and 12 months, respectively). Nearly 40% of RP patients received postoperative RT, primarily in the salvage setting. Five- and 10-year DMFS rates were significantly higher with EBRT+BT (91.6% and 81.3%) than with EBRT (79.6% and 65.8%; p < 0.0001) or RP (77.9% and 60.1%; p < 0.0001). Five- and 10-year PCSM rates were significantly lower with EBRT+BT (3.8% and 14.1%) than with EBRT (10.3% and 25.2%; 5- and 10-year hazard ratios of 0.38 and 0.47; p = 0.003) or RP (8.9% and 20.3%; 5- and 10-year hazard ratios of 0.39 and 0.55; p = 0.02). Overall 5- and 10-year OS rates were 85.7% and 64.7% and were similar between cohorts (p > 0.1). Conclusions: Extremely dose-escalated radiotherapy offered improved systemic control and reduced PCSM when compared with either EBRT or RP. Notably, this was achieved despite a significantly shorter median duration of ADT than in the EBRT arm. This is hypothesis generating as it suggests that improved local control via dose-escalation may have systemic control and survival implications even for patients with very high risk disease.

197 Background: The computerized ‘paperless’ medical recording system has transformed the modern health information system and serves as an idea platform for cancer registry development, particularly in a specialty like radiation oncology, where technological advances generate unprecedented amounts of data. Methods: From May 2011 to May 2015, physicians prospectively inputted data on patients seen during consultation in the Department of Radiation Oncology at UCLA. Using a customized interface established between an in-house registry and a commercially-available, hospital-based electronic medical record system (Epic Systems, Inc. Verona, WI), a parcel was created for data deposition, which was also linked to the Aria Treatment Planning Station (Varian Medical Systems, Inc., Palo Alto, CA). This registry was designed to assimilate into routine physician work-flow and was based on the completion of tabular entries, which were templated by disease sites. The total number of data fields per disease site ranged from 9 to 73 (median, 21). Results: A total of 7,646 patients were logged into the registry. Primary disease sites were prostate (N = 1,247), breast (N = 1157), head/neck (N = 726), central nervous system (N = 638), lung (N = 439), brain metastasis (N = 349), gastrointestinal (N = 238), gynecologic (N = 234), other (N = 2,618). The mean data capture completion rate by physicians was 55% (range, 32 to 65%); however, this rate did not differentiate between true incomplete (data available but not collected), versus data that was either unavailable, not required, or not applicable. A total of 46 independent, investigator-initiated research studies have been undertaken using queries supported by the registry from multiple access points, 8 of which were published in peer-reviewed journals. Conclusions: The development of a radiation oncology-specific registry not only enhanced research efficiency and facilitated quality assurance, but also fostered data reuse and promoted self-education by producing quality information to guide clinical practice. Our next steps include the integration of patient-reported outcomes through radiation oncology-specific surverys, the documentation of cost of delivery of care of specific treatment pathways, and the implementation of data collection processes in the community.

3D kinect camera systems are essential for real-time imaging of 3D treatment space that consists of both the patient anatomy as well as the treatment equipment setup. In this paper, we present the technical details of a 3D treatment room monitoring system that employs a scalable number of calibrated and coregistered Kinect v2 cameras. The monitoring system tracks radiation gantry and treatment couch positions, and tracks the patient and immobilization accessories. The number and positions of the cameras were selected to avoid line-of-sight issues and to adequately cover the treatment setup. The cameras were calibrated with a calibration error of 0.1 mm. Our tracking system evaluation show that both gantry and patient motion could be acquired at a rate of 30 frames per second. The transformations between the cameras yielded a 3D treatment space accuracy of < 2 mm error in a radiotherapy setup within 500mm around the isocenter.

Objective:Compared with standard, whole-gland (WG) therapies for prostate cancer, focal approaches may provide equivalent oncologic outcomes with fewer adverse effects. The purpose of this study was to compare organ-at-risk (OAR) dosimetry between hemigland (HG) and WG stereotactic body radiotherapy (SBRT) plans.Methods:Volumetric-modulated arc radiotherapy-based SBRT plans were designed to treat the left HG, right HG and WG in eight patients, using five fractions of 8 Gy. OARs of interest included the contralateral HG, rectum, urinary bladder, urethra, penile bulb and contralateral neurovascular bundle.Results:Rectal V80% (the percentage of a normal structure receiving a dose of 80%) and V90% were significantly lower with HG plans than with WG plans (median values of 4.4 vs 2.5 cm3 and 2.1 vs 1.1 cm3, respectively, p < 0.05 by Student's t-test). Bladder V50% was also reduced significantly in HG plans (32.3 vs 17.4 cm3, p < 0.05), with a trend towards reduction of V100% (3.4 vs 1.3 cm3, p = 0.09). Urethra...

Glioblastoma multiforme (GBM) frequently recurs at the same location after radiotherapy. Further dose escalation using conventional methods is limited by normal tissue tolerance. 4π non-coplanar radiotherapy has recently emerged as a new potential method to deliver highly conformal radiation dose using the C-arm linacs. We aim to study the feasibility of very substantial GBM dose escalation while maintaining normal tissue tolerance using 4π. 11 GBM patients previously treated with volumetric modulated arc therapy (VMAT/RapidArc) on the NovalisTx™ platform to a prescription dose of either 59.4 Gy or 60 Gy were included. All patients were replanned with 30 non-coplanar beams using a 4π radiotherapy platform, which inverse optimizes both beam angles and fluence maps. Four different prescriptions were used including original prescription dose and PTV (4πPTV_PD), 100 Gy to the PTV and GTV (4πPTV_100Gy), 100 Gy to the GTV only while maintaining prescription dose to the rest of the PTV (4πGTV_100Gy), and a 5 mm margin expansion plan (4πPTV_PD+5mm). OARs included in the study are the normal brain (brain – PTV), brainstem, chiasm, spinal cord, eyes, lenses, optical nerves, and cochleae. The 4π plans resulted in superior dose gradient indices, as indicated by >20% reduction in the R50, compared to the clinical plans. Among all of the 4π cases, when compared to the clinical plans, the maximum and mean doses were significantly reduced (p < 0.05) by a range of 47.01-98.82% and 51.87-99.47%, respectively, or unchanged (p > 0.05) for all of the non-brain OARs. Both the 4πPTV_PD and 4π GTV_100GYplans reduced the mean normal brain mean doses. 4π non-coplanar radiotherapy substantially increases the dose gradient outside of the PTV and better spares critical organs. Dose escalation to 100 Gy to the GTV or additional margin expansion while meeting clinical critical organ dose constraints is feasible. 100 Gy to the PTV result in higher normal brain doses but may be tolerated when delivered in proportionally increased treatment fractions. Therefore, 4π non-coplanar radiotherapy on C-arm gantry may provide an accessible tool to improve the outcome of GBM radiotherapy through extreme dose escalation.

118 Background: Although American Society for Radiation Oncology (ASTRO) guidelines support single fraction radiation treatment for uncomplicated bone metastases, it is rarely used. Methods: We used modified RAND/UCLA appropriateness methodology to understand how radiation oncologists make decisions about single fraction treatment to inform quality improvement. We focused on uncomplicated bone metastases (defined by relevant RCT exclusion criteria) without prior irradiation, pathologic fracture, or spinal cord compression. Eight radiation oncologists with varying sub-specialties were provided ASTRO guidelines, a summary table of RCT’s and recent research on current practices. They rated the appropriateness of 8Gy Single Fraction treatment and 4 alternative regimens for clinical cases before and after a panel discussion that also included three palliative care physicians. Clinical cases varied by location of metastases (spine, humeral head, femur, rib), size of metastases, patient prognosis, travel distance to treatment site, and patient age. We report findings based on final median appropriateness ratings and qualitative evaluation of discussion. Results: Single fraction treatment (8Gy) was rated as the most appropriate treatment, regardless of other factors if prognosis was 6 months or less. However, participants noted that prognostic information is often not available at the point of care. Use of greater than 10 fractions was rated as inappropriate regardless of other factors. Older age and travel distance were factors that lead to favoring 8Gy single fraction treatment. There was less consensus concerning single fraction treatment and favoring of other treatment approaches for lesions located on the spine, especially large lesions, and for patients with oligometastases and a longer prognosis where goals may include local tumor control in addition to palliation. Conclusions: Improving specification and communication of prognostic information is an important quality improvement target to enhance the patient-centered nature of care for patients with painful bone metastases.