Prospective evaluation of probabilistic dose-escalated IMRT in prostate cancer.
IMRT
coverage probability concept
dose escalation
probabilistic planned IMRT
prostate cancer
Journal
Radiology and oncology
ISSN: 1581-3207
Titre abrégé: Radiol Oncol
Pays: Poland
ID NLM: 9317213
Informations de publication
Date de publication:
22 12 2020
22 12 2020
Historique:
received:
31
08
2020
accepted:
02
11
2020
entrez:
22
4
2021
pubmed:
23
4
2021
medline:
21
9
2021
Statut:
epublish
Résumé
Cure- and toxicity rates after intensity-modulated radiotherapy (IMRT) of prostate cancer are dose-and volume dependent. We prospectively studied the potential for organ at risk (OAR) sparing and compensation of tumor movement with the coverage probability (CovP) concept. Twenty-eight prostate cancer patients (median age 70) with localized disease (cT1c-2c, N0, M0) and intermediate risk features (prostate-specific antigen [PSA] < 20, Gleason score ≤ 7b) were treated in a prospective study with the CovP concept. Planning-CTs were performed on three subsequent days to capture form changes and movement of prostate and OARs. The clinical target volume (CTV) prostate and the OARs (bladder and rectum) were contoured in each CT. The union of CTV1-3 was encompassed by an isotropic margin of 7 mm to define the internal target volume (ITV). Dose prescription/escalation depended on coverage of all CTVs within the ITV. IMRT was given in 39 fractions to 78 Gy using the Monte-Carlo algorithm. Short-term androgen deprivation was recommended and given in 78.6% of patients. Long-term toxicity was evaluated in 26/28 patients after a median follow-up of 7.1 years. At last follow-up, late bladder toxicity (Radiation Therapy Oncology Group, RTOG) G1 was observed in 14.3% of patients and late rectal toxicities (RTOG) of G1 (7.1%) and of G2 (3.6%) were observed. No higher graded toxicity occurred. After 7.1 years, biochemical control (biochemically no evidence of disease, bNED) was 95.5%, prostate cancer-specific survival and the distant metastasis-free survival after 7.1 years were 100% each. CovP-based IMRT was feasible in a clinical study. Dose escalation with the CovP concept was associated by a low rate of toxicity and a high efficacy regarding local and distant control.
Sections du résumé
BACKGROUND
Cure- and toxicity rates after intensity-modulated radiotherapy (IMRT) of prostate cancer are dose-and volume dependent. We prospectively studied the potential for organ at risk (OAR) sparing and compensation of tumor movement with the coverage probability (CovP) concept.
PATIENTS AND METHODS
Twenty-eight prostate cancer patients (median age 70) with localized disease (cT1c-2c, N0, M0) and intermediate risk features (prostate-specific antigen [PSA] < 20, Gleason score ≤ 7b) were treated in a prospective study with the CovP concept. Planning-CTs were performed on three subsequent days to capture form changes and movement of prostate and OARs. The clinical target volume (CTV) prostate and the OARs (bladder and rectum) were contoured in each CT. The union of CTV1-3 was encompassed by an isotropic margin of 7 mm to define the internal target volume (ITV). Dose prescription/escalation depended on coverage of all CTVs within the ITV. IMRT was given in 39 fractions to 78 Gy using the Monte-Carlo algorithm. Short-term androgen deprivation was recommended and given in 78.6% of patients.
RESULTS
Long-term toxicity was evaluated in 26/28 patients after a median follow-up of 7.1 years. At last follow-up, late bladder toxicity (Radiation Therapy Oncology Group, RTOG) G1 was observed in 14.3% of patients and late rectal toxicities (RTOG) of G1 (7.1%) and of G2 (3.6%) were observed. No higher graded toxicity occurred. After 7.1 years, biochemical control (biochemically no evidence of disease, bNED) was 95.5%, prostate cancer-specific survival and the distant metastasis-free survival after 7.1 years were 100% each.
CONCLUSIONS
CovP-based IMRT was feasible in a clinical study. Dose escalation with the CovP concept was associated by a low rate of toxicity and a high efficacy regarding local and distant control.
Identifiants
pubmed: 33885246
pii: raon-2020-0075
doi: 10.2478/raon-2020-0075
pmc: PMC7877263
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
88-96Informations de copyright
© 2021 Daniel Wegener, Bernhard Berger, Zhoulika Outtagarts, Daniel Zips, Frank Paulsen, Martin Bleif, Daniela Thorwarth, Markus Alber, Oliver Dohm, Arndt-Christian Müller, published by Sciendo.
Références
Acta Oncol. 2018 Aug;57(8):1003-1010
pubmed: 29882448
Lancet Oncol. 2016 Apr;17(4):464-474
pubmed: 26968359
J Natl Compr Canc Netw. 2010 Feb;8(2):162-200
pubmed: 20141676
Radiother Oncol. 2005 Jul;76(1):35-42
pubmed: 16019092
J Clin Oncol. 2006 May 1;24(13):1990-6
pubmed: 16648499
Strahlenther Onkol. 2009 Jul;185(7):438-45
pubmed: 19714305
N Engl J Med. 2016 Oct 13;375(15):1425-1437
pubmed: 27626365
Radiother Oncol. 2017 Apr;123(1):158-163
pubmed: 28190601
Acta Oncol. 2019 Jan;58(1):88-94
pubmed: 30264629
JAMA. 2005 Sep 14;294(10):1233-9
pubmed: 16160131
Semin Radiat Oncol. 2003 Jul;13(3):176-81
pubmed: 12903007
BMC Cancer. 2013 Jan 22;13:27
pubmed: 23336502
Int J Radiat Oncol Biol Phys. 2008 Jan 1;70(1):67-74
pubmed: 17765406
Radiat Oncol. 2015 May 21;10:115
pubmed: 25990489
Radiother Oncol. 2006 Jan;78(1):27-35
pubmed: 16216359
Int J Radiat Oncol Biol Phys. 1995 Mar 30;31(5):1341-6
pubmed: 7713792
Radiother Oncol. 2001 Dec;61(3):223-31
pubmed: 11730991
Eur Rev Med Pharmacol Sci. 2017 Aug;21(16):3563-3575
pubmed: 28925488
Int J Radiat Oncol Biol Phys. 2006 Jul 15;65(4):965-74
pubmed: 16798415
Eur Urol. 2017 Nov;72(5):712-735
pubmed: 28366513
Int J Radiat Oncol Biol Phys. 2009 Aug 1;74(5):1405-18
pubmed: 19616743
Lancet Oncol. 2014 Apr;15(4):464-73
pubmed: 24581940
J Clin Oncol. 2010 Mar 1;28(7):1106-11
pubmed: 20124169
Radiat Oncol. 2017 Jun 16;12(1):99
pubmed: 28622770
Radiother Oncol. 2018 Apr;127(1):74-80
pubmed: 29336835
Acta Oncol. 2020 Aug;59(8):911-917
pubmed: 32436467
Int J Radiat Oncol Biol Phys. 2012 Apr 1;82(5):1957-66
pubmed: 21640511