The clinical characterization shows the new unit provides a stable and flexible beam delivery platform suitable for IORT treatments. The simplified docking and collimated beam emission provides enhanced capabilities for patient treatment.

The advantages of highly conformal radiation treatments may be negated if patient anatomy changes. Here we characterize the reasons for re-simulation and adaptive re-planning. We conducted a chart-review of patients with locally advanced lung cancer treated with chemo-radiation. Inclusion criteria included: dose of at least 50 Gray (Gy), standard fractionation, treated between 1/2016-12/2018. Both small cell and non-small cell lung histologies were included, definitive and neoadjuvant. Exclusion criteria included SBRT, and adjuvant indications. We included patients that underwent re-simulation and adaptive re-planning during the course of treatment, performed at the discretion of the treating physician based upon carina / tumor miss-match on CBCT or if anatomical changes were observed on the CBCT or unsatisfactory simulation technique. Primary tumor (pGTV) and lymph nodes were contoured according to co-registered FDG PET/CT, without elective node irradiation and CBCT was used for IGRT. Reasons for re-planning for classified as: 1. Change in pGTV volume (> 20% compared with first scan) 2. Other major anatomical changes 3. Change of simulation technique (use of breath hold) Dosimetric parameters of lung V20, mean lung dose (MLD) and volume of heart receiving 40Gy (heart V40) were compared between first and second plan, after normalizing the prescription dose to 60 Gy. Statistical tests used: paired t test, Wilcoxon test. Out of 248 lung cancer patients, 48 cases underwent re-planning (19%). Male were 79%; histology: SCLC 9/48 (19%) and NSCLC 39/48 (81%). Stage 3a-3b in 92%. Mean radiation dose was 59.8 Gy (SD 3.4); planning technique VMAT 29/48 (60.4%), hybrid 8/48 (16.7%), and 3D-conformal 11/48 (23%). Tumor location was central in 26/48 (54%). Timing of re-planning was 1st third; 2nd third; final third in 23%, 46% and 31% respectively. 1. Changes in pGTV were observed in 41/48 (85%) of pts. pGTV decreased in volume in 36/41 (88%) of pts., mean decrease was -140.6 ml (range -7.7--475 ml). pGTV volume enlarged in 5/41(12%), mean increase: 56.8 ml (range 7-144 ml). 2. Other anatomical changes were observed in 18/48 (37%), including: pleural fluid accumulation, new atelectasis, resolution of atelectasis and absorption of pneumothorax. 3. Change in simulation technique was needed in 9/48 (18.7%) including breath hold or continuous positive airway pressure (CPAP) to expand the normal lung. Comparing the dosimetric variables between first and second plan: lung V20: 27.1Gy (SD 7.4) vs. 25.8Gy (SD 7) p=0.07, MLD 15.7Gy (SD 4) vs. 14.7Gy (SD 3.4) p=0.005, heart V40 was 10.9cc (SD 13.0) vs. 6.6cc (SD 9.5) p=0.004. Adaptive re-planning was performed in 19% of LA lung pts. who were monitored with daily IGRT-CBCT. In most cases tumor volume decreased or centrally located tumor caused distal atelectasis that resolved. These anatomical changes could potentially lead to increased toxicity and geographical miss, which can be corrected by adaptive re-planning.

Intra-fraction tumor motion during thoracic radiation remains a major challenge. Two alternative approaches to motion management during radiation therapy are the 4D-ITV approach and maximal inspiratory breath hold (MIBH). We have previously reported on the ability of CPAP to improve thoracic anatomy for lung irradiation using 4D-ITV: enlarging lung volumes and decreasing tumor movement compared to free breathing. We hypothesized that CPAP during MIBH would further optimize SBRT dosimetry compared with MIBH without CPAP. We performed a prospective study: patients underwent simulation twice - 'regular' MIBH, and MIBH combined with CPAP, for the latter patients were connected to the CPAP machine for 15 minutes prior to, and during the simulation. Contouring and planning were performed on both scans. Critical structures were defined as: heart, ribs, proximal bronchial tree. Radiation planning was performed using a commercially available treatment planning system, VMAT technique Eight patients underwent two simulations, 5 men and 3 women, mean age 67.5 age (49-74 years of age). Seven suffered from metastatic colorectal cancer, one thyroid cancer. CPAP+MIBH increased lung height by a median of 7%, width and breadth both by 2% compared to MIBH alone. Median lung volumes for MIBH and CPAP+MIBH were 4444cc (3913-6281) vs. 5265cc (4182-6441) respectively, p = 0.003. Hence CPAP increased BH volumes by a median 596cc (140cc-1275cc; 11.6%). Distance to closest critical structure increased from median 1.9cm (0.62-4.29cm) with MIBH to 2.4cm (0.65-4.9cm) for CPAP+MIBH, a median improvement 4.8mm (min 0.3mm; max 6.1mm) 25%, (p<0.03). Regarding dosimetric outcomes: the absolute mean decrease in lung V10 was 0.8% (range 0 – 1.3%; a 14% relative decrease, p<0.001) Compared to MIBH alone, CPAP combined with MIBH significantly improves thoracic geometry and dosimetry for thoracic SBRT by improving lung expansion, and increasing the distance between the GTV and critical structures. These improvements are likely to be critical in patients with large GTVs or multiple lung metastases. Further clinical investigation of reproducibility, functional and clinical outcomes is currently underway.

Many patients with upper-abdominal malignancies suffer from a characteristic syndrome of severe lower back pain radiating to the epigastrium, thought to be caused by involvement of the celiac plexus. Contemporary approaches (opioids, celiac blocks, systemic chemotherapy) are often inadequate. We hypothesized that ablative radiation delivered to the celiac plexus would alleviate pain levels. We performed a single-institution prospective clinical trial to evaluate a novel therapeutic approach: stereotactic radiation therapy focused on the celiac plexus. Eligibility criteria included typical celiac-pain syndrome, significant pain despite opioid usage (Numerical Rating Scale, NRS > 4/10), prognosis > 8 weeks, ECOG 0-3. Evaluable patients were defined as those completing treatment per protocol and completed at least one post-treatment visit. Exclusion criteria included previous abdominal RT. The anterolateral aspect of the aorta from D12 to L2 was used as a surrogate marker for the celiac plexus; primary tumor was irradiated according to physicians’ discretion. Radiation dose was originally 9 Gy*5, and later amended to a single fraction 25 Gy, both using VMAT. A dose-painting technique was used to limit dose to duodenum. The primary endpoint was pain-relief 3 weeks post-treatment, measured using NRS. Secondary endpoints included pain at 6 weeks, analgesic use, toxicity (CTCAE v4.03), and pain interference with seven daily activities as evaluated by the ‘Brief Pain Inventory' (BPI) instrument before and after radiation therapy. Analgesic use was not restricted. Twenty-one subjects were evaluable: 2 received 9Gy*5, 19 received 25Gy*1. The median age was 65 (range 37-83 years) with a Median ECOG of 1, 86% had pancreatic cancer. Median volume of celiac plexus was 30.8 cc, median dose to celiac plexus was 25 Gy. All patients reported decreased celiac pain: median pain level prior to RT was 6/10 (IQR 5-7.5) and reduced to 2.3/10 NRS score (IQR 0.9-3.3) (p <0.0005 compared to baseline) at 3 weeks (primary endpoint), and to 1.8/10 (IQR 0-3) (p <0.0005 compared to baseline) at 6 weeks’ post-treatment. 76% of patients reported a significant decrease of pain at primary endpoint (two point decrease), and in one third of patients the celiac pain had been eliminated entirely during follow-up. Toxicity was minimal and limited to grade 1-2 (2 patients reported mild worsening of pain immediately following treatment, some limited nausea/vomiting). Median daily morphine equivalent dose consumption decreased (NS). A significant improvement was noted in all evaluated measures of quality of life. Celiac plexus radiosurgery is well tolerated, substantially decreases pain, and improves quality of life amongst patients with advanced upper-GI cancer. An international multicenter phase II trial is currently accruing.

Material and MethodsTreatment planning was performed with the TPS Pinnacle 14 (Philips) using FF and FFF beams (6MV) for 10 patients who received a local irradiation (L-RT) of the whole breast (50Gy) with a simultaneous integrated boost of 60Gy, and for 10 patients who received a loco-regional (LR) RT with target volumes consisting of the supraclavicular area, the upper axilla and the internal mammary chain.For an identical PTV coverage (at least 95% of PTV covered by 95% of the prescribed dose), the dosimetric comparison between FF and FFF VMAT plans was undertaken for organs at risk (OAR), such as heart, ipsilateral lung, contralateral breast and lung.The mean dose (Dmean) and the V50Gy of the skin were also evaluated.Arcs' arrangements in both cases were kept identical and the delivery treatment time on the Elekta Agility 160 was calculated. ResultsThe mean PTV coverage was 96.5% and 97.3% for FF and FFF respectively.By using FFF beams, the mean heart dose was reduced from a mean value of 28% (0-75% range) for L-RT and from 16% (0-44%) for LR-RT.The Dmean at the ipsilateral lung was identical for L-RT but slightly decreased of 4% (0-15%) for LR-RT, when the V5Gy was 7 % (0-17%) reduced with FFF-beam for both L and LR RT.The V50Gy of the skin was also lower and decreased from 150% (0-900%) and from 95% (0-400%) for L and LR-RT respectively.The OARs' sparing (especially of the skin) observed with FFF was mainly due to a combination of factors: softer X spectra, sharp fall-off of the penumbra, less electrons' contamination, lower MLC transmission, lower patient's scattering, which induced less dose to the organs surrounding the PTV.The Dmean at the contralateral breast was identical for FF and FFF: 1.1±0.5Gyand 1.8±0.6Gyfor L and LR RT respectively.The V5Gy at the contralateral lung was negligible in all cases (<0.1Gy).As expected, the delivery time per arc with FFF beam was also reduced from 17±1s to 12±1s for L-RT and from 18±1s to 13±1s for LR-RT.Conclusion As expected, FFF-VMAT beams reduce the delivery time for a DIBH treatment which makes it more comfortable.PTV coverage is achieved with a dose reduction to OARs, especially the heart and ipsilateral lung, while preserving the contralateral organs during breath hold.

Modern developments in particle accelerator technology have opened the possibility for innovative approaches to external beam radiation therapies, particularly in area of electron therapy. The shallow penetration depths of current electron treatments may be expanded to include the full range of clinical depths >50 cm with the use of very high energy electrons in the range of 100-250 MeV. By magnetically coupling to the electron charge in the immediate vicinity of the target, novel methods for dose deposition may be explored. The work presented will outline the development of a novel delivery system to produce magnetically optimized very high energy electron therapy (MOVHEET). This method uses an array of magnets to dynamically modify the electron beam in order to produce dose peaks with >50% reduction in entrance dose by producing a converging beam within the target with reduced exit dose tails compared with photon beams. This technique modulates the dose peak depth by varying the magnet system parameters which allows for variable depth dose peaks that may be used to produce spread-out regions of dose similar to spread-out Bragg peaks in proton therapy. It is the goal of this work to introduce a novel modality of electron treatment with benefits similar to that of protons with significantly reduced space and cost that opens up new possibilities for external beam therapy.

To compare VMAT to dynamic conformal arc for planning fractionated radio surgery (FSR) for treatment of lesions involving the anterior optic apparatus (AOA). Nine patients with lesions apposed to the AOA were planned with either dynamic conformal non coplanar arcs (DCA) with iPlan software (Brainlab, Munich, Germany) or with volumetric intensity arc therapy (VMAT) using Eclipse software (Varian, Palo Alto, USA). The dose to the tumor boundaries was 25 Gy in 5 fractions delivered to the 80-90% isodose line in the DCA paradigm, and to the 95-99% isodose in the VMAT paradigm. Volumetric threshold dose of 23 Gy and maximal point dose of 25 Gy for AOA. The DCA plan was generated using 5 arcs with 4 or 5 couch angle positions while 3 different plans were generated using the VMAT for comparison: 1- using the same arcs, couch angle positions and optimization constraints as the DCA plan; 2 - two full arcs with couch angle 0o and one partial arc with couch angle 90o; 3 - one full arc with couch angle 0o and three partial arcs with couch angles 90o, 50o and 310o. The following parameters were used for comparison: Tumor Dmax,98%,95%,50%,2%, V98%,95%; AOA Dmax,2%,5%,10% and irradiation volumes V100%,95%,80%,50%, V100% in tumor volume (IT), V100% out of tumor volume (OT). We report statistical significant differences only. Mean tumor volume was 10.09 cc (0.22-24.8 cc). At least 98% of the tumor volume received at least 98% of the prescribed dose in all plans. AOA mean Dmax. was 26.86±1.54 Gy vs 23.39±1.07 Gy (p<0.00024), 23.91±0.4 Gy (p<0.00023) and 23.68±0.61 Gy (p<0.00028) in the DCA and the three VMAT plans respectively. AOA D2% was higher than 23 Gy in 78% and D5% and D10% in 67% of DCA plans. Although IT V100% was comparable for all plans, OT V100% (*) was better with the VMAT plans compared to the DCA 48.86±18.7 % (p<0.323), 35.24±14.05 % (p<0.0046), 39.02±22.44 % (p<0.0105) and 54.99±20.92 %: respectively. V95%, V80% and V50% for VMAT plan versions 2 and 3 were not significantly worse than DCA plans. VMAT allowed comparable tumor dose coverage with improved safety profile to AOA in tumors in intimate contact with the AOA. The need for quality assurance in VMAT complicates its use compared to DCA. On the other hand, radiation delivery itself is faster with VMAT (plan 2). Tumors volumes < 2cc complicates the VMAT optimization algorithm and increases the V100% OT. * - value normalized to tumor volume – (V100% / Vtumor) * 100%

CPAP used during radiation treatment reduces tumor motion and expands lung volume. CPAP's effect on the size, position, and motion of the heart has not been reported previously. We hypothesized that the physiologic effects seen with use of CPAP—expansion of the thoracic cavity caused by reduction of motion and flattening of the diaphragm as well as decreased venous return to the heart— affects cardiac parameters important for radiation treatment. We measured the effects of CPAP on the heart in a cohort of patients receiving radiation therapy for lung tumors. IRB approval was given in December 2013. Patients with primary or secondary lung tumors underwent 4-dimensional computed tomography (4DCT) simulation twice using identical positioning with free breathing and with CPAP. The heart was contoured according to RTOG guidelines on all 3D and 4D CT imaging studies. The Boolean operator function on the treatment planning system (TPS) was used to combine contours from all 10 respiratory phases of the 4D scans to create a maximal heart volume (MHV). The TPS was used to coregister all scans using the vertebral bodies for fusion and to measure and compare changes in the size, center of mass, and excursion of the heart and lung. A Wilcoxon signed-rank test was used to assess differences between variables. Spearman rho coefficient was used to assess correlations between changes in lung volume and measured heart parameters. Studies were reviewed from 9 patients. CPAP use decreased mean heart size on 3D and 4D scans by 6% (95% CI: 2%-8.5%, P<.008) and 13% (95% CI: 9%-16%, P<.008), respectively. CPAP decreased change in MHV by 46% (95% CI: 26%-65%, P<.01). CPAP shifted the mean center of mass caudally on 3D and 4D images by 1 cm (95% CI: 0.7 cm-1.4 cm, P<.01) and 1.1 cm (95% CI: 0.8 cm-1.5 cm, P<.01), respectively. Positional shifts in other directions were NS. CPAP reduced the mean excursion vector on 3D and 4D images by 4% (95% CI: 3%-6%, P<0.01) and 6% (95% CI: 5%-7%, P<0.01), respectively. Use of CPAP decreased the change in mean excursion by 36% (95%CI: 4%-67%, P= 0.01). CPAP increased lung volume by 30% (95% CI: 21%-39%, P< 0.01). Spearman correlation coefficient for increase in lung volume and caudal change in heart position and reduced heart excursion were 0.83 (P< 0.005) and 0.87 (P<0.003), respectively. Correlation with change in heart size was NS. The use of CPAP decreased heart size, shifted heart position caudally, reduced heart motion, and increased total lung volume. The increase in total lung volume was correlated with the changes observed in positon and motion of the heart. CPAP should be evaluated further as a novel cardiac motion management strategy to reduce heart exposure when offering radiation therapy.

To compare the achievement and cost of dose objectives defined for a European multicenter phase II trial of urethra-sparing SBRT using water vs. air-filled endorectal balloon (ERB). Ten patients simulated with a 100cc filled ERB for prostate SBRT were analyzed. Hounsfield units in the balloon were adjusted for comparison of air and water. Prescription dose to the PTV was 36.25 Gy in 5 fractions of 7.25 Gy. The urethral dose prescription (urethral planning risk volume, uPRV) was 32.5 Gy. Treatment plans were optimized using volumetric intensity-modulated arc treatment (VMAT) technique and dose was delivered with two arcs. We hypothesized that the optimization algorithm would perform better with water-filled EBR vs. air due to homogeneity of tissue density. Thus, two optimizations were run for each air-filled balloon: one with the same objective template as water and a second improved optimization (IO) which drives improved PTV coverage. The plans were compared for following parameters according to the research protocol: PTV98%, PTV95%, PTV2%, PTV-Rectal wall intersection PTV-R 98%, PTV-R2%, PTV-Rmean, RwallDmax, Rwall100%, Rwall90%, Rwall80%, Homogeneity Index HI PTV-R. The goal of PTV98% covered by the 95% prescription dose was achieved for all water-filled ERB and only 60% of air-filled ERB (P = 0.02, chi2). Improved optimization (IO) for air achieved the goal in 80% of air-filled ERB. The PTV-R98% (representing overlap of anterior rectal wall and PTV) dose coverage was significantly less for air vs. water: 89.1%±1.6 vs. 94.4%±1.6 (P<0.0001), but increased to 94.3%±1.8 with IO. The rectal volume Rwall100% was 0.25cc ±0.16 vs. 1.87cc ±0.69 for air vs. water (P<0.0002), however increases to 1.27cc ±0.67 for IO. Water-filled ERB provide superior PTV coverage than air at the cost of exposing a greater volume of rectal tissue to doses above 100% of the prescription dose. Strategies to improve PTV coverage for air-filled ERB succeed in most patients, yet will increase dose to the anterior rectal wall. The clinical impact of exposing minute volumes of rectal wall to ultra-high doses is unknown and will be clinically correlated with longer follow-up of patients treated in this protocol.

Purpose/Objective: Continuous Positive Airway Pressure (CPAP) has long been used in patients with obstructive sleep apnea to maintain airway patency.There are no reports describing CPAP use with radiation therapy.We performed a prospective clinical trial to determine if CPAP reduces tumor motion, expands lung volume and improves dosimetric parameters in patients receiving lung SBRT.Materials and Methods: IRB approval was given in December 2013.Inclusion criteria included adult patients with primary or secondary lung tumors referred for SBRT.Following informed consent and training, subjects underwent 4D simulation twice: without CPAP (free-breathing) and with CPAP.Treatment was planned using Eclipse (Varian).The ITV was expanded 5mm to create PTV.Volumetric and dosimetric parameters with and without CPAP were compared using Student's paired two-tailed t-test.CPAP was utilized during treatment if judged beneficial.Daily cone beam CT's were taken.Results: Twelve patients were enrolled, one subject withdrew due to mask discomfort, 11 were planned and 10 were treated to 18 different lesions.Mean dose (Eq2GY): 85 Gy (range: 32Gy-126Gy), One patient was treated with a SBRT boost and received 33Gy (Eq2Gy).CPAP increased mean lung volume by 26.4% (CI 95%, 20-32.8,p Conclusions: CPAP used during lung SBRT was safe, well tolerated, and provided clinical and dosimetric benefit in almost all patients.Compared to free breathing, CPAP increased total lung volume, decreased ITV and PTV, and reduced heart and lung dose.Clinical trials are in progress studying additional applications and optimal methods for use of this novel technique.

Spine stereotactic radiosurgery (SRS) delivers an accurate and conformal high radiation dose to the tumor in 1–5 sessions. Volumetric intensity-modulated arc treatment (VMAT) is currently used by the authors for spine SRS while patient's position is continuously monitored and corrected using Exact Track on board imaging (OBI) of BrainLab Robotic Radiosurgery System. We aim to highlight the advantages of VMAT based SRS by means of dose distribution, treatment time and clinical outcomes. Thirty six patients with 57 lesions were treated in our medical center. Dosimetric analysis was conducted for 35 lesions (21 patients). Ten consecutive lesions were planned using both IMRT (iPLAN, BrainLab) with 7 co-planar static fields and VMAT (RapidArc, Eclipse, Varian) using 2-3 dynamic arcs with a prescribed dose of 16Gy. The plans were compared for conformity (Dice Similarity Coefficient - DSC), homogeneity (HI), treatment delivery time and safety (spinal cord dose).For additional 25 lesions, with a prescribed dose of 16-18Gy, we calculated the same parameters for the VMAT plans alone. Four of these patients had skip lesions in 2 separate vertebral levels which were treated simultaneously. Toxicity and local control will be reported with a median follow up of 165 days. All evaluated parameters favored the VMAT plan over the IMRT plans. The Dmin in the IMRT was significantly lower than in the VMAT plan (7.65Gy/10.88Gy p=0.00002), the DSC was found to be significantly better for the VMAT plans compared to the IMRT plans (0.77/0.58 respectively p =0.01), and an almost 50% reduction in the net treatment time was calculated for the VMAT compared to the IMRT plans (6.73min/12.96min p<0.0002).The DSC, HI cord safety and treatment time in the additional 25 lesions were comparable or better than the above VMAT data. Conformity, homogeneity and safety parameters for four plans of simultaneous treatment of two closely lying lesions were comparable as well. Thirty four of 36 patients had at least one follow up visit 3 months post treatment. Two patients reported transient dysphagia and two suffered vertebral fracture (both were previously treated to the same area with standard radiation therapy). Local control rate in our cohort is 96.5% with only 2 local recurrences (5m and 12m post treatment). VMAT provides better conformity homogeneity and safety profile compared to IMRT with excellent local control and toxicity rates. It allows simultaneous treatment of closely situated separate vertebral lesions without compromising accuracy and safety. The shorter treatment time is a major advantage and provides not only convenience to the painful patient but contributes to the precision of this high dose radiation therapy.

Local failure of RT has been proposed as the rationale for surgery in HR prostate cancer, thus re-defining TX for pts thought to be suited primarily for RT. We report patterns of failure and outcomes of HR and vHR pts TX with high dose conformal RT, PLNRT, and ADT. Pt records from 11/2001-3/2012 were reviewed from an IRB approved database. HR and vHR were defined by NCCN guidelines. Three TX protocols were used: A. 2001-2009 3D conformal, B 2004-2011 IMRT ± IGRT, C 2011-2012 hypo-fractionation + VMAT+IGRT. Groups A and B received 78-82 Gy at 2Gy/fx. Group C received 73.6Gy at 2.3Gy/fx (82Gy 2gy/eq, σ/β=1.5). PLNRT for groups A and B was 46 Gy at 2Gy/fx and for group C was 54.4 Gy at 1.7 Gy/fx (50Gy 2 Gy/eq, α/β=1.5). ADT was prescribed for 6m-3 yrs. Side effects were recorded using CTCAE version 4. Disease fee survival (DFS) included metastatic, nodal, local and biochemical failures (bf, Phoenix definition). Kaplan Meyer (KM) method was used to determine probability of survival and toxicity. Cox univariate and multivariate regression analysis were used to determine significant covariates. P values ≤0.05 were considered significant. 203 pts with: Median age 74 yrs(range 56yrs-89yrs); Gl score <7 =15, 7 =45, >7 =143; >4 cores with Gl 8-10 =82; primary Gl pattern 5 =17; Median PSA 15.1ng/ml(range: 1.4– 449); PSA<40ng/ml =170, PSA≥40ng/ml =33); Clinical stage T2b ≤=85, T2c =19, T3a =62, ≥T3b =37; and NCCN risk group HR =100, vHR =103 were treated according to protocol A=29, B=60 or C=114. ADT duration: <2yrs =23 (11%), ≥2 yrs =174 (86%). One pt received no PLNRT or ADT, 1 no PLNRT and 5 no ADT. Median follow-up: 50m (range: 12m-142m). Toxicity ≥grade 3: Genitourinary; acute 6 (3%), late 21 (10%); Gastrointestinal; acute 2 (1%), late 7 (3.5%). Total failures: 30/203 pts (15%). Median time to failure: 30m (range: 4m-76m). Sites of recurrence: prostate 1, lymph nodes 3, bone 16, other sites 6 and bf 4. Deaths: 4 prostate cancer and 11 unrelated. KM estimate of 4 year DFS of the entire cohort was 87% (95% CI: 82%-92%). Only PSA predicted for DFS; PSA: PSA < 40ng/ml= 91% (95% CI: 85%-95%), PSA ≥ 40ng/ml= 68% (95% CI: 49%-82%) p=.001. Cox univariate analysis was significant for: PSA < 40 p=0.01; clinical stages T2c p=.004, T3b p=.02 and > 4 cores with Gl 8-10 p<.03. Multivariate analysis showed only PSA ≥ 40 ng/ml was significant (HR: 4.28, 95%CI: 1.98-9.25, p<0.001). Contemporary high dose conformal RT, PLNRT, and ADT is associated with excellent local control and DFS for HR and vHR pts with low toxicity. PSA ≥40ng/ml was associated with poor outcomes. Distant failure was dominant and local recurrence in the prostate was rare, challenging the notion that intensification of local therapy with surgery will provide benefit for HR pts.

Objective: To determine the effect of continuous positive airway pressure (CPAP) on tumor motion, lung volume, and dose to critical organs in patients receiving stereotactic body radiation therapy (SBRT) for lung tumors.Methods and Materials: After institutional review board approval in December 2013, patients with primary or secondary lung tumors referred for SBRT underwent 4-dimensional computed tomographic simulation twice: with free breathing and with CPAP. Tumor excursion was calculated by subtracting the vector of the greatest dimension of the gross tumor volume (GTV) from the internal target volume (ITV). Volumetric and dosimetric determinations were compared with the Wilcoxon signed-rank test. CPAP was used during treatment if judged beneficial.Results: CPAP was tolerated well in 10 of the 11 patients enrolled. Ten patients with 18 lesions were evaluated. The use of CPAP decreased tumor excursion by 0.5 +/- 0.8 cm, 0.4 +/- 0.7 cm, and 0.6 +/- 0.8 cm in the superioreinferior, righteleft, and anterior-posterior planes, respectively (P <= .02). Relative to free breathing, the mean ITV reduction was 27% (95% confidence interval [CI] 16%-39%, P < .001). CPAP significantly augmented lung volume, with a mean absolute increase of 915 +/- 432 cm(3) and a relative increase of 32% (95% CI 21%-42%, P = .003), contributing to a 22% relative reduction (95% CI 13%-32%, P = .001) in mean lung dose. The use of CPAP was also associated with a relative reduction in mean heart dose by 29% (95% CI 23%-36%, P = .001).Conclusion: In this pilot study, CPAP significantly reduced lung tumor motion compared with free breathing. The smaller ITV, the planning target volume (PTV), and the increase in total lung volume associated with CPAP contributed to a reduction in lung and heart dose. CPAP was well tolerated, reproducible, and simple to implement in the treatment room and should be evaluated further as a novel strategy for motion management in radiation therapy. (C) 2015 Elsevier Inc. All rights reserved.