Hypofractionated helical intensity-modulated radiotherapy of the prostate bed after prostatectomy with or without the pelvic lymph nodes - the PRIAMOS trial

BACKGROUND: While evidence on safety and efficacy of primary hypofractionated radiotherapy in prostate cancer is accumulating, data on postoperative hypofractionated treatment of the prostate bed and of the pelvic lymph nodes is still scarce. This phase II trial was initiated to investigate safety and feasibility of hypofractionated treatment of the prostate bed alone or with the pelvic lymph nodes. METHODS/DESIGN: A total of 80 prostate cancer patients with the indication for adjuvant radiotherapy will be enrolled, where 40 patients with a low risk of lymph node involvement (arm 1) and another 40 patients with a high risk of lymph node involvement (arm 2) will each receive 54 Gy in 18 fractions to the prostate bed. Arm 2 will be given 45 Gy to the pelvic lymph nodes additionally. Helical Tomotherapy and daily image guidance will be used. DISCUSSION: This trial was initiated to substantiate data on hypofractionated treatment of the prostate bed and generate first data on adjuvant hypofractionated radiotherapy of the pelvic lymph nodes. TRIAL REGISTRATION: ClinicalTrials.gov; NCT0162071

Helical intensity-modulated Radiotherapy of the Pelvic Lymph Nodes with Integrated Boost to the Prostate Bed - Initial Results of the PLATIN 3 Trial

BACKGROUND: Adjuvant and salvage radiotherapy of the prostate bed are established treatment options for prostate cancer. While the benefit of an additional radiotherapy of the pelvic lymph nodes is still under debate, the PLATIN 3 prospective phase II clinical trial was initiated to substantiate toxicity data on postoperative IMRT of the pelvic lymph nodes and the prostate bed. METHODS: From 2009 to 2011, 40 patients with high-risk prostate cancer after prostatectomy with pT3 R0/1 M0 or pT2 R1 M0 or a PSA recurrence and either > 20% risk of lymph node involvement and inadequate lymphadenectomy or pN + were enrolled. Patients received two months of antihormonal treatment (AT) before radiotherapy. AT continuation was mandatory during radiotherapy and was recommended for another two years. IMRT of the pelvic lymph nodes (51.0 Gy) with a simultaneous integrated boost to the prostate bed (68.0 Gy) was performed in 34 fractions. PSA level, prostate-related symptoms and quality of life were assessed at regular intervals for 24 months. RESULTS: Of the 40 patients enrolled, 39 finished treatment as planned. Overall acute toxicity rates were low and no acute grade 3/4 toxicity occurred. Only 22.5% of patients experienced acute grade 2 gastrointestinal (GI) and genitourinary (GU) toxicity. During follow-up, 10.0% late grade 2 GI and 5.0% late grade 2 GU toxicity occurred, and one patient developed late grade 3 proctitis and enteritis. After a median observation time of 24 months the PLATIN 3 trial has shown in 97.5% of all patients sufficient safety and thus met its prospectively defined aims. After a median of 24 months, 34/38 patients were free of a PSA recurrence. CONCLUSIONS: Postoperative whole-pelvis IMRT with an integrated boost to the prostate bed can be performed safely and without excessive toxicity. TRIAL REGISTRATION: Trial Numbers: ARO 2009–05, ClinicalTrials.gov: NCT01903408

Intensity-modulated versus 3-dimensional conformal radiotherapy in the definitive treatment of esophageal cancer: comparison of outcomes and acute toxicity

Background: Though the vast majority of seminal trials for locally advanced esophageal cancer (EC) utilized three-dimensional conformal radiotherapy (3DCRT), the advanced and highly conformal technology known as intensity-modulated radiotherapy (IMRT) can decrease doses to critical cardiopulmonary organs. To date, there have been no studies comparing both modalities as part of definitive chemoradiation (dCRT) for EC. Herein, we investigated local control and survival and evaluated clinical factors associated with these endpoints between cohorts. Methods: We retrospectively analyzed 93 patients (3DCRT n = 49, IMRT n = 44) who received dCRT at our institution between 2000 and 2012 with the histologic diagnosis of nonmetastatic EC, a Karnofsky performance status of ≥70, curative treatment intent, and receipt of concomitant CRT. Patients were excluded if receiving <50 Gy. Kaplan-Meier analysis was used to evaluate the endpoints of local relapse rate (LR), progression-free survival (PFS), and overall survival (OS). Cox proportional hazards modeling addressed factors associated with outcomes with univariate and multivariate approaches. Rates of acute toxicities and basic dosimetric parameters were compared between 3DCRT and IMRT patients. Results: Mean follow-up was 34.7 months. The 3-year LR was 28.6% in the 3DCRT group and 22.7% in the IMRT group (p = 0.620). Median PFS were 13.8 and 16.6 months, respectively (p = 0.448). Median OS were 18.4 and 42.0 months, respectively (p = 0.198). On univariate analysis, only cumulative radiation dose was associated with superior LR (hazard ratio (HR) 0.736; 95% confidence interval (CI) 0.635 – 0.916, p = 0.004). Factors clearly affecting survival were not observed. Conclusions: When comparing 3DCRT- versus IMRT-based dCRT, no survival benefits were observed. However, we found a lower local recurrence rate in the IMRT group potentially owing to dose-escalation. Prospective data are needed to verify the presented results herein

Accelerated large volume irradiation with dynamic Jaw/Dynamic Couch Helical Tomotherapy

BACKGROUND: Helical Tomotherapy (HT) has unique capacities for the radiotherapy of large and complicated target volumes. Next generation Dynamic Jaw/Dynamic Couch HT delivery promises faster treatments and reduced exposure of organs at risk due to a reduced dose penumbra. METHODS: Three challenging clinical situations were chosen for comparison between Regular HT delivery with a field width of 2.5 cm (Reg 2.5) and 5.0 cm (Reg 5.0) and DJDC delivery with a maximum field width of 5.0 cm (DJDC 5.0): Hemithoracic Irradiation, Whole Abdominal Irradiation (WAI) and Total Marrow Irradiation (TMI). For each setting, five CT data sets were chosen, and target coverage, conformity, integral dose, dose exposure of organs at risk (OAR) and treatment time were calculated. RESULTS: Both Reg 5.0 and DJDC 5.0 achieved a substantial reduction in treatment time while maintaining similar dose coverage. Treatment time could be reduced from 10:57 min to 3:42 min / 5:10 min (Reg 5.0 / DJDC 5.0) for Hemithoracic Irradiation, from 18:03 min to 8:02 min / 8:03 min for WAI and to 18:25 min / 18:03 min for TMI. In Hemithoracic Irradiation, OAR exposure was identical in all modalities. For WAI, Reg 2.5 resulted in lower exposure of liver and bone. DJDC plans showed a small but significant increase of ∼ 1 Gy to the kidneys, the parotid glans and the thyroid gland. While Reg 5.0 and DJDC were identical in terms of OAR exposure, integral dose was substantially lower with DJDC, caused by a smaller dose penumbra. CONCLUSIONS: Although not clinically available yet, next generation DJDC HT technique is efficient in improving the treatment time while maintaining comparable plan quality

Neurological outcome after emergency radiotherapy in MSCC of patients with non-small cell lung cancer - a prospective trial

Background: The aim of this trial was to investigate neurological outcome after emergency RT in MSCC of NSCLC patients with acute neurological deficit. Methods This pilot trial was prospective, non-randomized, and monocentre, ten patients were treated from July 2012 until June 2013. After onset of neurological symptoms RT was started within 12 hours. The neurological outcome was assessed at baseline, and six weeks after RT using the ASIA Impairment Scale (AIS). Results: The results showed an improved neurological outcome in one patient (10%), one patient (10%) had a decreased, and five patients (50%) a constant outcome after six weeks. Three patients (30%) died within the first six weeks following RT, additional 4 patients (40%) died within 4 month due to tumor progression. Conclusion: In this group of NSCLC patients we were able to show that emergency RT in MSCC with acute neurological deficit had no considerable benefit in neurological outcome. Therefore, short-course regime or best supportive care due to poor survival should be considered for these patients with additional distant metastases. Patients with favorable prognosis may be candidates for long-course RT. Trial Registration: Clinical trial identifier http://www.clinicaltrials.gov

Long-term results in malignant pleural mesothelioma treated with neoadjuvant chemotherapy, extrapleural pneumonectomy and intensity-modulated radiotherapy

Introduction: We investigated the clinical outcome and the toxicity of trimodal therapy of malignant pleural mesothelioma (MPM) treated with neoadjuvant chemotherapy, extrapleural pneumonectomy (EPP) and adjuvant intensity-modulated radiotherapy (IMRT). Methods: Chemotherapy regimens included Cisplatin/Pemetrexed, Carboplatin/Pemetrexed and Cisplatin/Gemcitabine, followed by EPP. 62 patients completed the adjuvant radiotherapy. IMRT was carried out in two techniques, either step&shoot or helical tomotherapy. Median target dose was 48 Gy to 54 Gy. Toxicity was scored with the Common Terminology Criteria (CTC) for Adverse Events. We used Kaplan-Meier method to estimate actuarial rate of locoregional control (LRC),distant control (DC) and overall survival (OS),measured from the date of surgery. Rates were compared using the logrank test. For multivariate analysis the Cox proportional hazard model was used. Results: The median OS, LRC and DC times were 20.4, 31.4 and 21.4 months. The 1-,2-,3-year OS rates were 63, 42, 28 %,the LRC rates were 81, 60, 40 %,and the DC rates were 62, 48, 41 %. We observed no CTC grade 4 or grade 5 toxicity. Step&shoot and helical tomotherapy were equivalent both in dosimetric characteristics and clinical outcome. Biphasic tumor histology was associated with worse clinical outcome compared to epitheloid histology. Conclusions: Mature clinical results of trimodal treatment for MPM were presented. They indicate that hemithoracic radiotherapy after EPP can be safely administered by either step&shoot IMRT and tomotherapy. However, the optimal prospective patient selection for this aggressive trimodal therapy approach remains unclear. This study can serve as a benchmark for current and future therapy concepts for MPM

High-dose single-fraction IMRT versus fractionated external beam radiotherapy for patients with spinal bone metastases: study protocol for a randomized controlled trial

Background: Stereotactic body radiation therapy (SBRT)using intensity-modulated radiotherapy (IMRT) can be a safe modality for treating spinal bone metastasis with enhanced targeting accuracy and an effective method for achieving good tumor control and a rigorous pain response. Methods/design: This is a single-center, prospective randomized controlled trial to evaluate pain relief after RT and consists of two treatment groups with 30 patients in each group. One group will receive single-fraction intensity-modulated RT with 1×24 Gy, and the other will receive fractionated RT with 10×3 Gy. The target parameters will be measured at baseline and at 3 and 6 months after RT. Discussion: The aim of this study is to evaluate pain relief after RT in patients with spinal bone metastases by means of two different techniques: stereotactic body radiation therapy and fractionated RT. The primary endpoint is pain relief at the 3-month time-point after RT. Secondly, quality of life, fatigue, overall and bone survival, and local control will be assessed. Trial registration ClinicalTrials.gov identifier NCT02358720 (June 2, 2015)

Intrafractional dose variation and beam configuration in carbon ion radiotherapy for esophageal cancer

Background: In carbon ion radiotherapy (CIR) for esophageal cancer, organ and target motion is a major challenge for treatment planning due to potential range deviations. This study intends to analyze the impact of intrafractional variations on dosimetric parameters and to identify favourable settings for robust treatment plans. Methods: We contoured esophageal boost volumes in different organ localizations for four patients and calculated CIR-plans with 13 different beam geometries on a free-breathing CT. Forward calculation of these plans was performed on 4D-CT datasets representing seven different phases of the breathing cycle. Plan quality was assessed for each patient and beam configuration. Results: Target volume coverage was adequate for all settings in the baseline CIR-plans (V95 > 98% for two-beam geometries, > 94% for one-beam geometries), but reduced on 4D-CT plans (V95 range 50–95%). Sparing of the organs at risk (OAR) was adequate, but range deviations during the breathing cycle partly caused critical, maximum doses to spinal cord up to 3.5x higher than expected. There was at least one beam configuration for each patient with appropriate plan quality. Conclusions: Despite intrafractional motion, CIR for esophageal cancer is possible with robust treatment plans when an individually optimized beam setup is selected depending on tumor size and localization

Biological in-vivo measurement of dose distribution in patients' lymphocytes by gamma-H2AX immunofluorescence staining: 3D conformal- vs. step-and-shoot IMRT of the prostate gland

<p>Abstract</p> <p>Background</p> <p>Different radiation-techniques in treating local staged prostate cancer differ in their dose- distribution. Physical phantom measurements indicate that for 3D, less healthy tissue is exposed to a relatively higher dose compared to SSIMRT. The purpose is to substantiate a dose distribution in lymphocytes <it>in-vivo </it>and to discuss the possibility of comparing it to the physical model of total body dose distribution.</p> <p>Methods</p> <p>For each technique (3D and SSIMRT), blood was taken from 20 patients before and 10 min after their first fraction of radiotherapy. The isolated leukocytes were fixed 2 hours after radiation. DNA double-strand breaks (DSB) in lymphocytes' nuclei were stained immunocytochemically using the gamma-H2AX protein. Gamma-H2AX foci inside each nucleus were counted in 300 irradiated as well as 50 non-irradiated lymphocytes per patient. In addition, lymphocytes of 5 volunteer subjects were irradiated externally at different doses and processed under same conditions as the patients' lymphocytes in order to generate a calibration-line. This calibration-line assigns dose-value to mean number of gamma-H2AX foci/ nucleus. So the dose distributions in patients' lymphocytes were determined regarding to the gamma-H2AX foci distribution. With this information a cumulative dose-lymphocyte-histogram (DLH) was generated. Visualized distribution of gamma-H2AX foci, correspondingly dose per nucleus, was compared to the technical dose-volume-histogram (DVH), related to the whole body-volume.</p> <p>Results</p> <p>Measured <it>in-vivo </it>(DLH) and according to the physical treatment-planning (DVH), more lymphocytes resulted with low-dose exposure (< 20% of the applied dose) and significantly fewer lymphocytes with middle-dose exposure (30%-60%) during Step-and-Shoot-IMRT, compared to conventional 3D conformal radiotherapy. The high-dose exposure (> 80%) was equal in both radiation techniques. The mean number of gamma-H2AX foci per lymphocyte was 0.49 (3D) and 0.47 (SSIMRT) without significant difference.</p> <p>Conclusions</p> <p><it>In-vivo </it>measurement of the dose distribution within patients' lymphocytes can be performed by detecting gamma-H2AX foci. In case of 3D and SSIMRT, the results of this method correlate with the physical calculated total body dose-distribution, but cannot be interpreted unrestrictedly due to the blood circulation. One possible application of the present method could be in radiation-protection for <it>in-vivo </it>dose estimation after accidental exposure to radiation.</p

Intensity modulated radiotherapy (IMRT) in the treatment of children and Adolescents - a single institution's experience and a review of the literature

<p>Abstract</p> <p>Background</p> <p>While IMRT is widely used in treating complex oncological cases in adults, it is not commonly used in pediatric radiation oncology for a variety of reasons. This report evaluates our 9 year experience using stereotactic-guided, inverse planned intensity-modulated radiotherapy (IMRT) in children and adolescents in the context of the current literature.</p> <p>Methods</p> <p>Between 1999 and 2008 thirty-one children and adolescents with a mean age of 14.2 years (1.5 - 20.5) were treated with IMRT in our department. This heterogeneous group of patients consisted of 20 different tumor entities, with Ewing's sarcoma being the largest (5 patients), followed by juvenile nasopharyngeal fibroma, esthesioneuroblastoma and rhabdomyosarcoma (3 patients each). In addition a review of the available literature reporting on technology, quality, toxicity, outcome and concerns of IMRT was performed.</p> <p>Results</p> <p>With IMRT individualized dose distributions and excellent sparing of organs at risk were obtained in the most challenging cases. This was achieved at the cost of an increased volume of normal tissue receiving low radiation doses. Local control was achieved in 21 patients. 5 patients died due to progressive distant metastases. No severe acute or chronic toxicity was observed.</p> <p>Conclusion</p> <p>IMRT in the treatment of children and adolescents is feasible and was applied safely within the last 9 years at our institution. Several reports in literature show the excellent possibilities of IMRT in selective sparing of organs at risk and achieving local control. In selected cases the quality of IMRT plans increases the therapeutic ratio and outweighs the risk of potentially increased rates of secondary malignancies by the augmented low dose exposure.</p