LOW DOSE BATH FROM IMPT VS. IMXT FOR THE PELVIC AREA WHEN TREATING ADVANCED PROSTATE CANCER

2019 ◽  
Vol 186 (2-3) ◽  
pp. 377-380
Author(s):  
Matěj Navrátil ◽  
Vladimír Vondráček ◽  
Michal Andrlík ◽  
Jiří Kubeš ◽  
Jozef Rosina ◽  
...  
Keyword(s):  
Advanced Prostate Cancer ◽  
Low Dose ◽  
X Ray ◽  
Intensity Modulated Proton Therapy ◽  
Intensity Modulated ◽  
Typical Specimen ◽  
Pelvic Area ◽  
Integrated Boost ◽  
Target Volumes ◽  
Treatment Plans

Abstract Twenty (10 intensity-modulated proton therapy (IMPT) and 10 intensity-modulated x-ray therapy (IMXT) treatment plans for patients with advanced prostate carcinoma were compared in this study. All chosen patients were indicated for prostate and pelvic lymph nodes irradiation using simultaneous integrated boost technique. These patients represent typical specimen for this diagnose. IMPT irradiates just half of the tissue volume with a low dose (up to 10 cobalt gray equivalent) compared to IMXT without compromise in target volumes coverage and in this way reduces the risk of secondary cancer development or other possible complications.

scholarly journals Dosimetric comparison of jaw tracking in intensity modulated and volumetric modulated arc radiotherapy for carcinoma of cervix

2019 ◽  
Vol 25 (3) ◽  
pp. 155-164
Author(s):  
Karthick Raj Mani ◽  
Muhtasim Aziz Muneem ◽  
Nazneen Sultana ◽  
Tanjina Hossain ◽  
Tabinda Basharat ◽  
...  
Keyword(s):  
Femoral Head ◽  
Dose Reduction ◽  
Low Dose ◽  
Intensity Modulated Radiotherapy ◽  
Conformity Index ◽  
P Value ◽  
Intensity Modulated ◽  
Carcinoma Of Cervix ◽  
Target Volumes ◽  
Volumetric Modulated Arc Radiotherapy

Abstract Aim: To study the dosimetric advantages of the jaw tracking technique in intensity-modulated radiotherapy (IMRT) and volumetric modulated arc radiotherapy (VMAT) for carcinoma of cervix patients. Materials and Methods: We retrospectively selected ten previously treated cervix patients in this study. All the ten patients underwent CT simulation along with immobilization and positional devices. Targets and organ at risks (OARs) were delineated slice by slice for all the patients. All the patients were planned for IMRT and VMAT with intend to deliver 50 Gy in 25 fractions. All the plans were planned with 6 MV photon beam using millennium-120 multi leaf collimator (MLC) using the TrueBeam linear accelerator. IMRT and VMAT plans were performed with jaw tracking (JT) and with static jaw (SJ) techniques by keeping the same constraints and priorities for the target volumes and critical structures for a particular patient. For standardization, all the plans were normalized to the target mean of the planning target volume. All the plans were accepted with the criteria of bladder mean dose < 40 Gy and rectum mean dose < 40 Gy without compromising the target volumes. Target conformity, dose to the critical structures and low dose volumes were recorded and analyzed for IMRT and VMAT plans with and without jaw tracking for all the patients. Results: The conformity index average of all patients followed by standard deviation (̄x± σ̄x) for JT-IMRT, SJ-IMRT, JT-VMAT and SJ-VMAT were 1.176 ± 0.139, 1.175 ± 0.139, 1.193 ± 0.220 and 1.228 ± 0.192 and homogeneity index were 0.089 ± 0.022, 0.085 ± 0.024, 0.102 ± 0.016 and 0.101 ± 0.016. In low dose volume J,T-IMRT shows a 5.4% (p-value < 0.001) overall reduction in volume receiving at least 5 Gy (V5) compared to SJ-IMRT, whereas 1.2% reduction was observed in V5 volume in JT-VMAT compared to SJ-VMAT. JT-IMRT showed mean reduction in rectum and bladder of 1.34% (p-value < 0.001) and 1.46% (p-value < 0.001) compared to SJ-IMRT, while only 0.30% and 0.03% reduction were observed between JT-VMAT and SJ-VMAT. JT-IMRT plans also showed considerable dose reduction to inthe testine, right femoral head, left femoral head and cauda compared to the SJ-IMRT plans. Conclusion: Jaw tracking resulted in decreased dose to critical structures in IMRT and VMAT plans. But significant dose reductions were observed for critical structures in the JT-IMRT compared to SJ-IMRT technique. In JT-VMAT plans dose reduction to the critical structures were not significant compared to the JT-IMRT due to relatively lesser monitor units in the VMAT plans.

scholarly journals Post-Irradiation Sinus Mucosa Disease in Nasopharyngeal Carcinoma Patients Treated with Intensity-Modulated Proton Therapy

Cancers ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 225
Author(s):  
Pei-Wen Wu ◽  
Chien-Chia Huang ◽  
Yun-Shien Lee ◽  
Yung-Chih Chou ◽  
Kang-Hsing Fan ◽  
...  
Keyword(s):  
Proton Therapy ◽  
Nasopharyngeal Cancer ◽  
Post Irradiation ◽  
Intensity Modulated Proton Therapy ◽  
Intensity Modulated ◽  
Target Volumes ◽  
Mri Scans ◽  
Magnetic Resonance Imaging Mri ◽  
Sinus Mucosa

In the past decade, patients with nasopharyngeal cancer (NPC) have been deemed candidates for proton radiotherapy, due to the large and comprehensive target volumes and the necessity for the retention of the surrounding healthy tissues. In this study, we aimed to compare the incidence and severity of post-irradiation sinusitis by detecting sinus mucosa diseases (SMDs) via the magnetic resonance imaging (MRI) of patients with NPC after intensity-modulated proton therapy (IMPT) and volume-modulated arc therapy (VMAT). A total of 53 patients in the IMPT group and 54 patients in the VMAT group were enrolled in this study. There were significantly lower endoscopic scores and Lund–Mackay staging scores determined from MRI scans in the IMPT group during different follow-up periods. For the most vulnerable sinuses, the incidence and severity of SMD were the highest during the third post-radiotherapy month in both groups. These decreased steadily, and there was no significant increase in the incidence and severity of SMD during the second post-radiotherapy year in the IMPT group. Our data show that NPC patients with IMPT have a significantly lower incidence and decreased severity of SMD than those with VMAT. A better and faster recovery of sinonasal function after radiotherapy in the IMPT group was also observed.

MO-D-M100J-01: Dose Painting With Intensity Modulated Proton Therapy and Intensity Modulated X-Ray Therapy: A Comparison

2007 ◽  
Vol 34 (6Part15) ◽  
pp. 2522-2523 ◽  
Author(s):  
R Flynn ◽  
D Barbee ◽  
S Bowen ◽  
K McCall ◽  
S Bentzen ◽  
...  
Keyword(s):  
Proton Therapy ◽  
Dose Painting ◽  
X Ray ◽  
Intensity Modulated Proton Therapy ◽  
Intensity Modulated

scholarly journals The Potential Role of Intensity-Modulated Proton Therapy in Hepatic Carcinoma in Mitigating the Risk of Dose De-Escalation

2020 ◽  
Vol 19 ◽  
pp. 153303382098041
Author(s):  
Luca Cozzi ◽  
Tiziana Comito ◽  
Mauro Loi ◽  
Antonella Fogliata ◽  
Ciro Franzese ◽  
...  
Keyword(s):  
At Risk ◽  
Proton Therapy ◽  
Organs At Risk ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Proton Therapy ◽  
Intensity Modulated ◽  
Number Of Patients ◽  
Target Volumes ◽  
Dosimetric Analysis

Purpose: To investigate the role of intensity-modulated proton therapy (IMPT) for hepatocellular carcinoma (HCC) patients to be treated with stereotactic body radiation therapy (SBRT) in a risk-adapted dose prescription regimen. Methods: A cohort of 30 patients was retrospectively selected as “at-risk” of dose de-escalation due to the proximity of the target volumes to dose-limiting healthy structures. IMPT plans were compared to volumetric modulated arc therapy (VMAT) RapidArc (RA) plans. The maximum dose prescription foreseen was 75 Gy in 3 fractions. The dosimetric analysis was performed on several quantitative metrics on the target volumes and organs at risk to identify the relative improvement of IMPT over VMAT and to determine if IMPT could mitigate the need of dose reduction and quantify the consequent potential patient accrual rate for protons. Results: IMPT and VMAT plans resulted in equivalent target dose distributions: both could ensure the required coverage for CTV and PTV. Systematic and significant improvements were observed with IMPT for all organs at risk and metrics. An average gain of 9.0 ± 11.6, 8.5 ± 7.7, 5.9 ± 7.1, 4.2 ± 6.4, 8.9 ± 7.1, 6.7 ± 7.5 Gy was found in the near-to-maximum doses for the ribs, chest wall, heart, duodenum, stomach and bowel bag respectively. Twenty patients violated one or more binding constraints with RA, while only 2 with IMPT. For all these patients, some dose de-intensification would have been required to respect the constraints. For photons, the maximum allowed dose ranged from 15.0 to 20.63 Gy per fraction while for the 2 proton cases it would have been 18.75 or 20.63 Gy. Conclusion: The results of this in-silico planning study suggests that IMPT might result in advantages compared to photon-based VMAT for HCC patients to be treated with ablative SBRT. In particular, the dosimetric characteristics of protons may avoid the need for dose de-escalation in a risk-adapted prescription regimen for those patients with lesions located in proximity of dose-limiting healthy structures. Depending on the selection thresholds, the number of patients eligible for treatment at the full dose can be significantly increased with protons.

scholarly journals Comparison of intensity modulated photon therapy and intensity modulated proton therapy plans for prostate cancer

2015 ◽  
Vol 18 (3) ◽  
pp. 93-100
Author(s):  
Tu Thi Cam Nguyen ◽  
Nhon Van Mai ◽  
Binh Thai Nguyen
Keyword(s):  
At Risk ◽  
Proton Therapy ◽  
Organs At Risk ◽  
X Rays ◽  
Work Intensity ◽  
Normal Tissues ◽  
Intensity Modulated Proton Therapy ◽  
Intensity Modulated ◽  
Dose Volume ◽  
Treatment Plans

Nowadays, traditional radiation therapy using x-rays is still the most common type of external exposure in curing cancer. However, the persisting problem is that significant dose delivered to normal tissues because of the characteristics of interaction of photons with matter even with the most advanced delivery techniques such as IMRT, IGRT, etc. Proton therapy is not only the technique producing better conformity to target but also better sparing to organs at risk. In this work, intensity modulated proton therapy (IMPT) and intensity modulated photon therapy (IMRT) plans are generated for a prostate patient. The evaluation and comparison of the two treatment plans were performed in term of physical quantity based on Dose Volume Histogram (DVH) and dose statistics for both target and organs at risk. The results of our study show that IMPT could be beneficial compared to IMRT with 5 fields. The doses to intestine and bladder are low resulting in possibly reducing side effects and second malignancies

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