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Rectal retractor in prostate radiotherapy: pros and cons. Radiat Oncol 2022; 17:204. [PMID: 36494732 PMCID: PMC9737745 DOI: 10.1186/s13014-022-02176-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022] Open
Abstract
Dose escalation in prostate radiotherapy (RT) have led to improved biochemical controls and reduced the risk of distant metastases. Over the past three decades, despite technological advancements in RT planning and delivery, the rectum is a dose-limiting structure in prostate RT owing to the close anatomical proximity of the anterior rectal wall (ARW) to the prostate gland. RT-induced rectal toxicities remain a clinical challenge, limiting the prescribed dose during prostate RT. To address the spatial proximity challenge by physically increasing the distance between the posterior aspect of the prostate and the ARW, several physical devices such as endorectal balloons (ERBs), rectal hydrogel spacers, and rectal retractor (RR) have been developed. Previously, various aspects of ERBs and rectal hydrogel spacers have extensively been discussed. Over recent years, given the interest in the application of RR in prostate external beam radiotherapy (EBRT), this editorial will discuss opportunities and challenges of using RR during prostate EBRT and provide information regarding which aspects of this device need attention.
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Intrafraction Prostate Motion Management for Ultra-Hypofractionated Radiotherapy of Prostate Cancer. Curr Oncol 2022; 29:6314-6324. [PMID: 36135065 PMCID: PMC9497512 DOI: 10.3390/curroncol29090496] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/22/2022] [Accepted: 08/29/2022] [Indexed: 11/17/2022] Open
Abstract
Purpose: Determine the time-dependent magnitude of intrafraction prostate displacement and a cutoff for the tracking decision. Methods: Nine patients with localized prostate cancer were treated with ultra-hypofractionated radiotherapy (CyberKnife) with fiducial markers. Exact tract kV/kV imaging was used with an average interval of 19−92 s. A Gaussian distribution was calculated for the x-, y-, and z-directions (σx,y,z). The variation of prostate motion (μσ) was obtained by averaging the patients’ specifics, and the safety margin was calculated to be MAB = WYm + WBSs. Results: The calculated PTV safety margins were as follows: at 40 s: 0.55 mm (L/r), 0.85 mm (a/p), and 1.05 mm (s/i); at 60 s: 0.9 mm (L/r), 1.35 mm (a/p), and 1.55 mm (s/i); at 100 s: 1.5 mm (L/r), 2.3 mm (a/p), and 2.6 mm (s/i); at 150 s: 1.9 mm (L/r), 3.1 mm (a/p), and 3.6 mm (s/i); at 200 s: 2.2 mm (L/r), 3.8 mm (a/p), and 4.2 mm (s/i); and at 300 s: 2.6 mm (L/r), 5.3 mm (a/p), and 5.6 mm (s/i). A tracking cutoff of 2.5 min seemed reasonable. In order to achieve an accuracy of < 1 mm, tracking with < 50 s intervals was necessary. Conclusions: For ultra-hypofractionated radiotherapy of the prostate with treatment times > 2.5 min, intrafraction motion management is recommended.
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Greco C, Pares O, Pimentel N, Louro V, Nunes B, Kociolek J, Stroom J, Vieira S, Mateus D, Cardoso MJ, Soares A, Marques J, Freitas E, Coelho G, Fuks Z. Urethra Sparing With Target Motion Mitigation in Dose-Escalated Extreme Hypofractionated Prostate Cancer Radiotherapy: 7-Year Results From a Phase II Study. Front Oncol 2022; 12:863655. [PMID: 35433469 PMCID: PMC9012148 DOI: 10.3389/fonc.2022.863655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 02/24/2022] [Indexed: 11/15/2022] Open
Abstract
Purpose To explore whether the rectal distension-mediated technique, harnessing human physiology to achieve intrafractional prostate motion mitigation, enables urethra sparing by inverse dose painting, thus promoting dose escalation with extreme hypofractionated stereotactic ablative radiotherapy (SABR) in prostate cancer. Materials and Methods Between June 2013 and December 2018, 444 patients received 5 × 9 Gy SABR over 5 consecutive days. Rectal distension-mediated SABR was employed via insertion of a 150-cm3 air-inflated endorectal balloon. A Foley catheter loaded with 3 beacon transponders was used for urethra visualization and online tracking. MRI-based planning using Volumetric Modulated Arc Therapy - Image Guided Radiotherapy (VMAT-IGRT) with inverse dose painting was employed in delivering the planning target volume (PTV) dose and in sculpting exposure of organs at risk (OARs). A 2-mm margin was used for PTV expansion, reduced to 0 mm at the interface with critical OARs. All plans fulfilled Dmean ≥45 Gy. Target motion ≥2 mm/5 s motions mandated treatment interruption and target realignment prior to completion of the planned dose delivery. Results Patient compliance to the rectal distension-mediated immobilization protocol was excellent, achieving reproducible daily prostate localization at a patient-specific retropubic niche. Online tracking recorded ≤1-mm intrafractional target deviations in 95% of treatment sessions, while target realignment in ≥2-mm deviations enabled treatment completion as scheduled in all cases. The cumulative incidence rates of late grade ≥2 genitourinary (GU) and gastrointestinal (GI) toxicities were 5.3% and 1.1%, respectively. The favorable toxicity profile was corroborated by patient-reported quality of life (QOL) outcomes. Median prostate-specific antigen (PSA) nadir by 5 years was 0.19 ng/ml. The cumulative incidence rate of biochemical failure using the Phoenix definition was 2%, 16.6%, and 27.2% for the combined low/favorable–intermediate, unfavorable intermediate, and high-risk categories, respectively. Patients with a PSA failure underwent a 68Ga-labeled prostate-specific membrane antigen (68Ga-PSMA) scan showing a 20.2% cumulative incidence of intraprostatic relapses in biopsy International Society of Urological Pathology (ISUP) grade ≥3. Conclusion The rectal distension-mediated technique is feasible and well tolerated. Dose escalation to 45 Gy with urethra-sparing results in excellent toxicity profiles and PSA relapse rates similar to those reported by other dose-escalated regimens. The existence of intraprostatic recurrences in patients with high-risk features confirms the notion of a high α/β ratio in these phenotypes resulting in diminished effectiveness with hypofractionated dose escalation.
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Affiliation(s)
- Carlo Greco
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Oriol Pares
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Nuno Pimentel
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Vasco Louro
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Beatriz Nunes
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Justyna Kociolek
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Joep Stroom
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Sandra Vieira
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Dalila Mateus
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Maria Joao Cardoso
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Ana Soares
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Joao Marques
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Elda Freitas
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Graça Coelho
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | - Zvi Fuks
- Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal.,Memorial Sloan Kettering Cancer Center, New York, NY, United States
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Extreme Hypofractionation with SBRT in Localized Prostate Cancer. Curr Oncol 2021; 28:2933-2949. [PMID: 34436023 PMCID: PMC8395496 DOI: 10.3390/curroncol28040257] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/24/2021] [Accepted: 07/27/2021] [Indexed: 02/07/2023] Open
Abstract
Prostate cancer is the most commonly diagnosed cancer among men around the world. Radiotherapy is a standard of care treatment option for men with localized prostate cancer. Over the years, radiation delivery modalities have contributed to increased precision of treatment, employing radiobiological insights to shorten the overall treatment time, improving the control of the disease without increasing toxicities. Stereotactic body radiation therapy (SBRT) represents an extreme form of hypofractionated radiotherapy in which treatment is usually delivered in 1–5 fractions. This review assesses the main efficacy and toxicity data of SBRT in non-metastatic prostate cancer and discusses the potential to implement this scheme in routine clinical practice.
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Taillez A, Bimbai AM, Lacornerie T, Le Deley MC, Lartigau EF, Pasquier D. Studies of Intra-Fraction Prostate Motion During Stereotactic Irradiation in First Irradiation and Re-Irradiation. Front Oncol 2021; 11:690422. [PMID: 34336678 PMCID: PMC8316636 DOI: 10.3389/fonc.2021.690422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/28/2021] [Indexed: 12/01/2022] Open
Abstract
Background Understanding intra-fractional prostate motions is crucial for stereotactic body radiation therapy (SBRT). No studies have focused on the intra-fractional prostate motions during re-irradiation with SBRT. The objective was to evaluate these translational and rotational motions in primary treated patients and in the context of re-irradiation. Methods From January 2011 to March 2020, 162 patients with histologically proven prostate cancer underwent prostate SBRT, including 58 as part of a re-irradiation treatment. We used the continuous coordinates of the fiducial markers collected by an orthogonal X-ray dual-image monitoring system. The translations and rotations of the prostate were calculated. Prostate deviations representing overall movement was defined as the length of the 3D-vectors. Results A total of 858 data files were analyzed. The deviations over time in the group of primary treated patients were significantly larger than that of the group of re-irradiation, leading to a mean deviation of 2.73 mm (SD =1.00) versus 1.90 mm (SD =0.79), P<0.001. In the re-irradiation group, we identified displacements of -0.05 mm (SD =1.53), 0.20 mm (SD =1.46); and 0.42 mm (SD =1.24) in the left-right, superior-inferior and anterior-posterior planes. Overall, we observed increasing deviations over the first 30 min followed by a stabilization related to movements in the three translational axes. Conclusion This is the first study to focus on intrafraction prostate motions in the context of re-irradiation. We observed that intra-fraction prostate motions persisted in the setting of re-irradiation, although they showed a significant reduction when compared with the first irradiation. These results will help to better estimate random errors during SBRT treatment of intra-prostatic recurrence after irradiation.
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Affiliation(s)
- Alexandre Taillez
- Academic Department of Radiation Oncology, Oscar Lambret Comprehensive Cancer Center, Lille, France.,University of Lille, Lille, France
| | - Andre-Michel Bimbai
- Department of Biostatistics, Oscar Lambret Comprehensive Cancer Center, Lille, France
| | - Thomas Lacornerie
- Department of Medical Physics, Oscar Lambret Comprehensive Cancer Center, Lille, France
| | - Marie-Cecile Le Deley
- Department of Biostatistics, Oscar Lambret Comprehensive Cancer Center, Lille, France
| | - Eric F Lartigau
- Academic Department of Radiation Oncology, Oscar Lambret Comprehensive Cancer Center, Lille, France.,University of Lille, Lille, France.,CRISTAL UMR CNRS 9189, University of Lille, Lille, France
| | - David Pasquier
- Academic Department of Radiation Oncology, Oscar Lambret Comprehensive Cancer Center, Lille, France.,University of Lille, Lille, France.,CRISTAL UMR CNRS 9189, University of Lille, Lille, France
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Clinical Effect of Radiotherapy Combined with Capecitabine after Neoadjuvant Therapy for Rectal Cancer. JOURNAL OF ONCOLOGY 2021; 2021:9972051. [PMID: 34194503 PMCID: PMC8203376 DOI: 10.1155/2021/9972051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 05/25/2021] [Indexed: 11/17/2022]
Abstract
Objective The purpose of the study was to investigate the clinical effect of radiotherapy combined with capecitabine in rectal cancer patients after neoadjuvant therapy. Methods 80 rectal cancer patients who underwent neoadjuvant therapy in our hospital from February 2016 to February 2018 were selected as the study subjects and divided into the control group (n = 40) and experimental group (n = 40) according to the order of admission. Among them, the control group was treated with radiotherapy, while the experimental group was treated with radiotherapy combined with capecitabine. The therapeutic efficacy, CEA levels, the incidence and recurrence rate of adverse reactions, as well as the progression-free survival and survival rate after 2-year treatment were analyzed in the two groups. Results The effective rate of treatment in the experimental group of 87.5% (35/40) was significantly higher than 50% (20/40) in the control group, with statistical significance (X2 = 13.09, P < 0.001). After treatment, the CEA levels in the two groups both decreased significantly, and the CEA level in the experimental group of 3.75 ± 1.76 ng/ml was significantly lower than 7.35 ± 2.11 ng/ml in the control group, with statistical significance (T = 8.29, P < 0.001). The incidence and the recurrence rate of adverse reactions of 5% (2/40) and 10% (4/40), respectively, in the experimental group were significantly lower than those of 40% (16/40) and 30% (12/40) in the control group, with statistical significance (X2 = 14.05, 5.00, P < 0.001, 0.05). After the 2-year follow-up, it was found that the progression-free survival of 21.53 ± 6.23 months in the experimental group was significantly longer than that of 18.18 ± 5.41 months in the control group, with statistical significance (T = 2.57, P < 0.05), and the 2-year survival rate of 97.5% (39/40) in the experimental group was significantly higher than 80% (32/40) in the control group, with statistical significance (T = 6.13, P < 0.05). Conclusion Radiotherapy combined with capecitabine in rectal cancer patients after neoadjuvant therapy can improve the therapeutic efficacy with fewer adverse reactions and longer patients' survival, which is worthy of popularization and application after neoadjuvant therapy for rectal cancer.
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Arefpour AM, Abbasi M, Rabi Mahdavi S, Shafieesabet M, Fadavi P. Clinical effects of rectal retractor application in prostate cancer radiotherapy. Med J Islam Repub Iran 2021; 35:69. [PMID: 34277506 PMCID: PMC8278024 DOI: 10.47176/mjiri.35.69] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Indexed: 11/09/2022] Open
Abstract
Background: Radiation-induced rectal toxicities remain as a major risk during prostate radiotherapy. One approach to the reduction of rectal radiation dose is to physically increase the distance between the rectal wall and prostate. Therefore, the aim of this study was to evaluate whether the application of the rectal retractor (RR) can reduce rectal dose and toxicity in prostate cancer 3-dimensional conformal radiotherapy (3D-CRT).
Methods: Overall, 36 patients with localized prostate cancer were randomized into the 2 groups, 18 patients with RR in-place and 18 without RR. All patients underwent planning computed tomography (CT). Patients were treated with 70 Gy in 35 fractions of 3D-CRT. In the RR group, RR was used during cone-down 20 treatment fractions. Acute and late gastrointestinal (GI) toxicities were assessed using EORTC/RTOG scoring system weekly during radiotherapy, 3, and 12 months after treatment. Device-related events were recorded according to CTCAE version 4.0. Patient characteristics, cancer differences, and dosimetric data for the RR and non-RR groups were compared using a Man-Whitney U test for continuous variables, and Fisher exact test for categorical data. The EORTC/RTOG scores for the 2 groups were compared using Fisher exact test. A P value <0.05 was considered statistically significant.
Results: A RR significantly reduced mean dose (Dmean) to the rectum as well as rectal volume receiving 50% to 95% (V50-95%) of prescribed dose. The absolute reduction of rectal Dmean was 10.3 Gy. There was no statistically significant difference in acute GI toxicity between groups during treatment or at 3 months. At 12 months, 2 patients in the RR group and 9 in the control group experienced late grade ≥ 1 GI toxicity (p=0.027). No patients in the RR group reported late grade ≥ 2 GI toxicity, whereas 3 patients in the control group experienced late grade 2 GI toxicity. In the RR group, 6 patients reported grade 1 rectal discomfort and pain according to CTCAE version 4.0.
Conclusion: The application of the RR showed a significant rectum sparing effect, resulting in substantially reducing late GI toxicity.
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Affiliation(s)
- Amir Mohammad Arefpour
- Department of Radiation Oncology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mahshid Abbasi
- Department of Radiation Oncology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Seied Rabi Mahdavi
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.,Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mahdiyeh Shafieesabet
- Department of Radiation Oncology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Pedram Fadavi
- Department of Radiation Oncology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
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MR-Guided Hypofractionated Radiotherapy: Current Emerging Data and Promising Perspectives for Localized Prostate Cancer. Cancers (Basel) 2021; 13:cancers13081791. [PMID: 33918650 PMCID: PMC8070332 DOI: 10.3390/cancers13081791] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/01/2021] [Accepted: 04/02/2021] [Indexed: 12/13/2022] Open
Abstract
Simple Summary The biological features of prostate cancer as a tumor with a low alpha beta ratio have led clinicians to consider the use of higher doses per fraction, thus gaining an advantage both in terms of clinical outcomes and of logistic opportunities. To date, moderate hypofractionated schedules are supported by several international clinical guidelines. The subsequent step was represented by the adoption of extreme hypofractionated schedules, for which recent literature data report non-inferiority results for the five-fractions regimens. In this scenario, the recent introduction of MR-guided daily adaptive radiotherapy is a potential paradigm shift, given the ability to increase the resolution of the pelvis anatomy and to take into account of the daily variations in shape and size of the nearby healthy structures. Abstract In this review we summarize the currently available evidence about the role of hybrid machines for MR-guided radiotherapy for prostate stereotactic body radiotherapy. Given the novelty of this technology, to date few data are accessible, but they all report very promising results in terms of tolerability and preliminary clinical outcomes. Most of the studies highlight the favorable impact of on-board magnetic resonance imaging as a means to improve target and organs at risk identification with a consequent advantage in terms of dosimetric results, which is expected to relate to a more favorable toxicity pattern. Still, the longer treatment time per session may potentially affect the patient’s compliance to the treatment, although first quality of life assessment studies have reported substantial tolerability and no major impact on quality of life. Finally, in this review we hypothesize some future scenarios of further investigation, based on the possibility to explore the superior anatomy visualization and the role of daily adapted treatments provided by hybrid MR-Linacs.
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Ghaffari H, Navaser M, Refahi S. In regard to Cuccia et al.: impact of hydrogel peri-rectal spacer insertion on prostate gland intra-fraction motion during 1.5 T MR-guided stereotactic body radiotherapy. Radiat Oncol 2020; 15:199. [PMID: 32807168 PMCID: PMC7433034 DOI: 10.1186/s13014-020-01642-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 08/12/2020] [Indexed: 02/07/2023] Open
Abstract
We read the article entitled “Impact of hydrogel peri-rectal spacer insertion on prostate gland intra-fraction motion during 1.5 T MR-guided stereotactic body radiotherapy” with great interest. In that study, the author reported that there is a statistically significant difference in the rotational antero-posterior shifts between the spacer and the non-spacer groups. Also, there was no statistically significant difference between the groups in terms of translational shifts. However, there are some points about the study. In this letter, we aimed to clarify these points.
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Affiliation(s)
- Hamed Ghaffari
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
| | - Mahmoud Navaser
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Soheila Refahi
- Department of Medical Physics, Faculty of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
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Effectiveness of rectal displacement devices in managing prostate motion: a systematic review. Strahlenther Onkol 2020; 197:97-115. [DOI: 10.1007/s00066-020-01633-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 05/05/2020] [Indexed: 12/12/2022]
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11
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de Muinck Keizer DM, Kontaxis C, Kerkmeijer LGW, van der Voort van Zyp JRN, van den Berg CAT, Raaymakers BW, Lagendijk JJW, de Boer JCJ. Dosimetric impact of soft-tissue based intrafraction motion from 3D cine-MR in prostate SBRT. Phys Med Biol 2020; 65:025012. [PMID: 31842008 DOI: 10.1088/1361-6560/ab6241] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
To investigate the dosimetric impact of intrafraction translation and rotation motion of the prostate, as extracted from daily acquired post-treatment 3D cine-MR based on soft-tissue contrast, in extremely hypofractionated (SBRT) prostate patients. Accurate dose reconstruction is performed by using a prostate intrafraction motion trace which is obtained with a soft-tissue based rigid registration method on 3D cine-MR dynamics with a temporal resolution of 11 s. The recorded motion of each time-point was applied to the planning CT, resulting in the respective dynamic volume used for dose calculation. For each treatment fraction, the treatment delivery record was generated by proportionally splitting the plan into 11 s intervals based on the delivered monitor units. For each fraction the doses of all partial plan/dynamic volume combinations were calculated and were summed to lead to the motion-affected fraction dose. Finally, for each patient the five fraction doses were summed, yielding the total treatment dose. Both daily and total doses were compared to the original reference dose of the respective patient to assess the impact of the intrafraction motion. Depending on the underlying motion of the prostate, different types of motion-affected dose distributions were observed. The planning target volumes (PTVs) ensured CTV_30 (seminal vesicles) D99% coverage for all patients, CTV_35 (prostate corpus) coverage for 97% of the patients and GTV_50 (local boost) for 83% of the patients when compared against the strict planning target D99% value. The dosimetric impact due to prostate intrafraction motion in extremely hypofractionated treatments was determined. The presented study is an essential step towards establishing the actual delivered dose to the patient during radiotherapy fractions.
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Draulans C, De Roover R, van der Heide UA, Haustermans K, Pos F, Smeenk RJ, De Boer H, Depuydt T, Kunze-Busch M, Isebaert S, Kerkmeijer L. Stereotactic body radiation therapy with optional focal lesion ablative microboost in prostate cancer: Topical review and multicenter consensus. Radiother Oncol 2019; 140:131-142. [PMID: 31276989 DOI: 10.1016/j.radonc.2019.06.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 12/25/2022]
Abstract
Stereotactic body radiotherapy (SBRT) for prostate cancer (PCa) is gaining interest by the recent publication of the first phase III trials on prostate SBRT and the promising results of many other phase II trials. Before long term results became available, the major concern for implementing SBRT in PCa in daily clinical practice was the potential risk of late genitourinary (GU) and gastrointestinal (GI) toxicity. A number of recently published trials, including late outcome and toxicity data, contributed to the growing evidence for implementation of SBRT for PCa in daily clinical practice. However, there exists substantial variability in delivering SBRT for PCa. The aim of this topical review is to present a number of prospective trials and retrospective analyses of SBRT in the treatment of PCa. We focus on the treatment strategies and techniques used in these trials. In addition, recent literature on a simultaneous integrated boost to the tumor lesion, which could create an additional value in the SBRT treatment of PCa, was described. Furthermore, we discuss the multicenter consensus of the FLAME consortium on SBRT for PCa with a focal boost to the macroscopic intraprostatic tumor nodule(s).
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Affiliation(s)
- Cédric Draulans
- Department of Radiation Oncology, University Hospitals Leuven, Belgium; Department of Oncology, KU Leuven, Belgium.
| | - Robin De Roover
- Department of Radiation Oncology, University Hospitals Leuven, Belgium; Department of Oncology, KU Leuven, Belgium.
| | - Uulke A van der Heide
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
| | - Karin Haustermans
- Department of Radiation Oncology, University Hospitals Leuven, Belgium; Department of Oncology, KU Leuven, Belgium.
| | - Floris Pos
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
| | - Robert Jan Smeenk
- Department of Radiation Oncology, Radboud University Medical Centre, Nijmegen, The Netherlands.
| | - Hans De Boer
- Department of Radiation Oncology, University Medical Center, Utrecht, The Netherlands.
| | - Tom Depuydt
- Department of Radiation Oncology, University Hospitals Leuven, Belgium; Department of Oncology, KU Leuven, Belgium.
| | - Martina Kunze-Busch
- Department of Radiation Oncology, Radboud University Medical Centre, Nijmegen, The Netherlands.
| | - Sofie Isebaert
- Department of Radiation Oncology, University Hospitals Leuven, Belgium; Department of Oncology, KU Leuven, Belgium.
| | - Linda Kerkmeijer
- Department of Radiation Oncology, Radboud University Medical Centre, Nijmegen, The Netherlands; Department of Radiation Oncology, University Medical Center, Utrecht, The Netherlands.
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Afkhami Ardekani M, Ghaffari H. Optimization of prostate brachytherapy techniques with polyethylene glycol-based hydrogel spacers: A systematic review. Brachytherapy 2019; 19:13-23. [PMID: 31542390 DOI: 10.1016/j.brachy.2019.08.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/01/2019] [Accepted: 08/21/2019] [Indexed: 01/07/2023]
Abstract
PURPOSE The objective of this overview was to critically evaluate the effect of polyethylene glycol (PEG)-based hydrogel spacers during prostate brachytherapy with regard to dosimetric and clinical benefits, as well as procedure-related toxicity. METHODS AND MATERIALS A systematic search in the PubMed database was performed. RESULTS A total of 12 studies, involving 615 patients with PEG hydrogel injection, were included. Overall, patients well tolerated the implantation of PEG hydrogel spacers with an excellent safety profile. However, although there were some procedure-related complications, rates of these complications were very rare. Toxicities related to the spacer were limited to Grade 1 rectal discomfort and pain (9/615 patients), Grade 2 rectal ulceration (1 in 615 patients), perineal abscess (1 in 615 patients), and bacterial prostatitis (2/615 patients) according to Common Terminology Criteria for Adverse Events v4.0 grading scheme. The application of PEG hydrogel spacers significantly reduced radiation doses to the rectum during prostate brachytherapy in the different setting. Although there was no prospective randomized clinical trial, retrospective studies showed that reducing rectal doses by the implantation of PEG hydrogel may result in an improvement in rectal toxicity. CONCLUSIONS The insertion of hydrogel spacers is safe, resulting in a significant decrease in rectal doses. This may lead to a reduction in rectal or gastrointestinal toxicity. Prospective randomized clinical trials are warranted to confirm the clinical impact of rectal dosimetric improvements.
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Affiliation(s)
- Mahdieh Afkhami Ardekani
- Department of Radiology, Faculty of Para-Medicine, Hormozgan University of Medical Sciences, Bandar-Abbas, Iran
| | - Hamed Ghaffari
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
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