MRI-guided focal boost to dominant intraprostatic lesion using volumetric modulated arc therapy in prostate cancer. Results of a phase II trial
- PMID: 34538073
- PMCID: PMC8978233
- DOI: 10.1259/bjr.20210683
MRI-guided focal boost to dominant intraprostatic lesion using volumetric modulated arc therapy in prostate cancer. Results of a phase II trial
Abstract
Objective: To determine morphological and biological control as well as toxicity and quality of life (QoL) of men with localized prostate cancer (PCa) treated with MRI-guided focal boost radiotherapy.
Material and methods: 30 patients with PCa and a visible dominant intraprostatic lesion (DIL) identified on mpMRI were included in a prospective Phase II trial. Matching point registration of planning CT and T2W, diffusion-weighted and a gradient-recalled echo (GRE) MRI images made in treatment position was used for prostate and tumour delineation. Treatment consisted on 35 daily fractions of 2.17 Gy with a concomitant focal boost to the DIL of 2.43 Gy using volumetric modulated arc therapy (VMAT) and image-guided radiation therapy (IGRT) with intraprostatic fiducial markers. Biochemical failure was analysed using PSA nadir +2 ng/mL criteria and local control using mpMRI evaluation at 6-9 months following RT. Acute and late toxicity were defined according to CTCAE v.4.0 and RTOG/EORTC scales and QoL was assessed using IPSS, EPIC short-form and UCLA-PCI questionnaires.
Results: The median radiation dose to the prostate was 77.6 Gy (IQR 77.3-78.1), and to the DIL was 85.5 Gy (IQR 85.0-86.0). With a median follow up of 30.0 months (IQR 25.5-40.27), all patients remain free of biochemical relapse. An mpMRI complete response was observed in 25 patients during the first post-treatment evaluation at 6 months. The remaining five patients achieved a complete disappearance of the DIL both on T2 and DWI on the second mpMRI performed at 9 months following treatment. Six out of 30 (20%) patients presented acute Grade 2 urinary toxicity with no Grade 3 acute complications. Acute rectal toxicity was only found in 2 (6.6%) patients (both Grade 1). Only late Grade 1 urinary and rectal complications were observed in 3/30 patients, respectively, with no Grade 2 or more late toxicity. The urinary, bowel and sexual bother EPIC scores were slightly and insignificantly increased in the first 3 months post-treatment, returning to normal afterwards.
Conclusions: mpMRI-guided focal boost using VMAT hypofractionated technique is associated with an excellent morphological and functional response control and a safe toxicity profile.
Advances in knowledge: In the present trial, we examined the potential role of mpMRI for radiological assessment (functional and morphological) of treatment response in high-risk prostate cancer patients treated with MRI-guided focal radiotherapy dose intensification to dominant Intraprostatic lesion.
Figures
References
-
- Pucar D, Hricak H, Shukla-Dave A, Kuroiwa K, Drobnjak M, Eastham J, et al. . Clinically significant prostate cancer local recurrence after radiation therapy occurs at the site of primary tumor: magnetic resonance imaging and step-section pathology evidence. Int J Radiat Oncol Biol Phys 2007; 69: 62–9. doi: 10.1016/j.ijrobp.2007.03.065 - DOI - PubMed
-
- Arrayeh E, Westphalen AC, Kurhanewicz J, Roach M, Jung AJ, Carroll PR, et al. . Does local recurrence of prostate cancer after radiation therapy occur at the site of primary tumor? results of a longitudinal MRI and MRSI study. Int J Radiat Oncol Biol Phys 2012; 82: e787–93. doi: 10.1016/j.ijrobp.2011.11.030 - DOI - PMC - PubMed
-
- Aluwini S, van Rooij P, Hoogeman M, Kirkels W, Kolkman-Deurloo I-K, Bangma C. Stereotactic body radiotherapy with a focal boost to the MRI-visible tumor as monotherapy for low- and intermediate-risk prostate cancer: early results. Radiat Oncol 2013; 8: 84. doi: 10.1186/1748-717X-8-84 - DOI - PMC - PubMed
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Medical
Research Materials
Miscellaneous
