A study of the clinical, treatment planning and dosimetric feasibility of dose painting in external beam radiotherapy of prostate cancer.

Computer-assisted/methods Feasibility studies Focal boost Intensity-modulated/methods Magnetic resonance imaging Multi-parametric MRI Prostate radiotherapy Radiotherapy Radiotherapy dosage Radiotherapy planning Urethra

Journal

Physics and imaging in radiation oncology
ISSN: 2405-6316
Titre abrégé: Phys Imaging Radiat Oncol
Pays: Netherlands
ID NLM: 101704276

Informations de publication

Date de publication:
Jul 2020
Historique:
received: 23 01 2020
revised: 26 07 2020
accepted: 27 07 2020
entrez: 18 1 2021
pubmed: 19 1 2021
medline: 19 1 2021
Statut: epublish

Résumé

Radiotherapy dose painting is a promising technique which enables dose escalation to areas of higher tumour cell density within the prostate which are associated with radioresistance, known as dominant intraprostatic lesions (DILs). The aim of this study was to determine factors affecting the feasibility of radiotherapy dose painting in patients with high and intermediate risk prostate cancer. Twenty patients were recruited into the study for imaging using a 3 T magnetic resonance imaging (MRI) scanner. Identified DILs were outlined and the scan registered with the planning computed tomography (CT) dataset. Intensity-modulated plans were produced and evaluated to determine the effect of the organ-at-risk constraints on the dose that could be delivered to the DILs. Measurements were made to verify that the distribution could be safely delivered. MRI scans were obtained for nineteen patients. Fourteen patients had one to two DILs with ten overlapping the urethra and/or rectum. The target boost of 86 Gy was achieved in seven plans but was limited to 80 Gy for five patients whose boost volume overlapped or abutted the urethra. Dosimetric measurements gave a satisfactory gamma pass rate at 3%/3 mm. It was feasible to produce dose-painted plans for a boost of 86 Gy for approximately half the patients with DILs. The main limiting factor was the proximity of the urethra to the boost volumes. For a small proportion of patients, rigid registration between CT and MRI images was not adequate for planning purposes.

Sections du résumé

BACKGROUND AND PURPOSE OBJECTIVE
Radiotherapy dose painting is a promising technique which enables dose escalation to areas of higher tumour cell density within the prostate which are associated with radioresistance, known as dominant intraprostatic lesions (DILs). The aim of this study was to determine factors affecting the feasibility of radiotherapy dose painting in patients with high and intermediate risk prostate cancer.
MATERIALS & METHODS METHODS
Twenty patients were recruited into the study for imaging using a 3 T magnetic resonance imaging (MRI) scanner. Identified DILs were outlined and the scan registered with the planning computed tomography (CT) dataset. Intensity-modulated plans were produced and evaluated to determine the effect of the organ-at-risk constraints on the dose that could be delivered to the DILs. Measurements were made to verify that the distribution could be safely delivered.
RESULTS RESULTS
MRI scans were obtained for nineteen patients. Fourteen patients had one to two DILs with ten overlapping the urethra and/or rectum. The target boost of 86 Gy was achieved in seven plans but was limited to 80 Gy for five patients whose boost volume overlapped or abutted the urethra. Dosimetric measurements gave a satisfactory gamma pass rate at 3%/3 mm.
CONCLUSIONS CONCLUSIONS
It was feasible to produce dose-painted plans for a boost of 86 Gy for approximately half the patients with DILs. The main limiting factor was the proximity of the urethra to the boost volumes. For a small proportion of patients, rigid registration between CT and MRI images was not adequate for planning purposes.

Identifiants

pubmed: 33458328
doi: 10.1016/j.phro.2020.07.005
pii: S2405-6316(20)30039-7
pmc: PMC7807863
doi:

Types de publication

Journal Article

Langues

eng

Pagination

66-71

Informations de copyright

© 2020 The Authors.

Déclaration de conflit d'intérêts

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Références

Eur Radiol. 2012 Apr;22(4):746-57
pubmed: 22322308
J Med Radiat Sci. 2017 Mar;64(1):25-34
pubmed: 28263041
Radiother Oncol. 2019 Apr;133:100-105
pubmed: 30935564
Technol Cancer Res Treat. 2017 Dec;16(6):1067-1078
pubmed: 29332454
Rev Urol. 2014;16(2):67-75
pubmed: 25009446
Lancet Oncol. 2015 Dec;16(16):1605-16
pubmed: 26522334
Int J Radiat Oncol Biol Phys. 2000 Jul 1;47(4):1121-35
pubmed: 10863086
Semin Radiat Oncol. 2011 Apr;21(2):101-10
pubmed: 21356478
Med Phys. 2015 Oct;42(10):6090-7
pubmed: 26429284
Biomed Res Int. 2018 Jan 24;2018:7569590
pubmed: 29619375
Med Phys. 2018 Oct;45(10):e908-e922
pubmed: 30168155
Radiother Oncol. 2019 Nov;140:131-142
pubmed: 31276989
Clin Oncol (R Coll Radiol). 2017 Jan;29(1):e49
pubmed: 27448432
Int J Radiat Oncol Biol Phys. 2020 Mar 15;106(4):715-724
pubmed: 31812718
Radiography (Lond). 2017 Nov;23(4):310-313
pubmed: 28965894
Acta Oncol. 2018 May;57(5):574-581
pubmed: 29260950
Phys Med Biol. 2018 Feb 26;63(5):05TR01
pubmed: 29393071
Med Phys. 1998 May;25(5):656-61
pubmed: 9608475
Clin Transl Radiat Oncol. 2020 Sep 01;25:22-28
pubmed: 32995575
Lancet Oncol. 2012 Jan;13(1):43-54
pubmed: 22169269
J Clin Oncol. 2006 May 1;24(13):1990-6
pubmed: 16648499
Int J Radiat Oncol Biol Phys. 2018 Nov 15;102(4):912-921
pubmed: 29859785
Trials. 2011 Dec 05;12:255
pubmed: 22141598
Clin Oncol (R Coll Radiol). 2016 Mar;28(3):165-70
pubmed: 26482453
Lancet Oncol. 2016 Aug;17(8):1047-1060
pubmed: 27339115
Clin Oncol (R Coll Radiol). 2018 Nov;30(11):711-719
pubmed: 30201276

Auteurs

Steve W Blake (SW)

Medical Physics, Bristol Haematology and Oncology Centre, Bristol BS2 8ED, UK.

Alison Stapleton (A)

Medical Physics, Bristol Haematology and Oncology Centre, Bristol BS2 8ED, UK.

Andrew Brown (A)

Medical Physics, Bristol Haematology and Oncology Centre, Bristol BS2 8ED, UK.

Sian Curtis (S)

Bioengineering, Innovation & Research Hub, Medical Physics, St Michael's Hospital, Bristol BS2 8EG, UK.
Clinical Research and Imaging Centre (CRICBristol), Bristol BS2 8DX, UK.

Janice Ash-Miles (J)

Radiology, North Bristol NHS Trust, Bristol BS10 5NB, UK.

Emma Dennis (E)

Oncology, Bristol Haematology and Oncology Centre, Bristol BS2 8ED, UK.

Susan Masson (S)

Oncology, Bristol Haematology and Oncology Centre, Bristol BS2 8ED, UK.

Dawn Bowers (D)

Oncology, Bristol Haematology and Oncology Centre, Bristol BS2 8ED, UK.

Serena Hilman (S)

Oncology, Bristol Haematology and Oncology Centre, Bristol BS2 8ED, UK.

Classifications MeSH