Online Adaptive Stereotactic Body Radiotherapy for Localized Prostate Cancer
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: radiotherapy.
- Who it may be relevant to
- Registry conditions: Localized Prostate Carcinoma, Prostate Cancer (Adenocarcinoma), Prostate Hyperplasia, Lower Urinary Track Symptoms. Basic parameters: from 18 years · Male.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Germany, Switzerland
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Online Adaptive Stereotactic Body Radiotherapy for Localized Prostate Cancer in Patients With Lower Urinary Tract Symptoms and/or Prostate Hyperplasia (X-SMILE)
Overview
The aim of this phase II international multicenter study is to evaluate the safety, feasibility, and efficacy of CT or MRI-adaptive SBRT, delivered in five weekly fractions, in patients with newly diagnosed localized prostate cancer who have lower urinary tract symptoms and/or prostatic hyperplasia.
Detailed description
Background: Stereotactic body radiotherapy (SBRT) for localized prostate cancer has demonstrated non-inferior oncological outcomes and toxicity profiles to conventionally or moderately hypofractioned radiotherapy regimens, while offering the advantage of shorter treatment durations. However, SBRT may not be suitable for all patients, particularly those with lower urogenital tract symptoms and/or prostatic hyperplasia.
Methods: This study aims to evaluate the safety and efficacy of weekly computed tomography (CT) or magnetic resonance image-guided (MRI) online adaptive SBRT in patients with intermediate to (very) high-risk localized prostate cancer who present with lower urinary tract symptoms (International Prostate Symptom Score \[IPSS\] \> 12) and/or have prostate hyperplasia (prostate volume \>60 mL). The primary outcome measure is urogenital toxicity grade ≥3 within 3 months after completion of SBRT (according to CTCAE V5.0 and RTOG) or discontinuation of therapy. Our aim is to show that the event rate is at 3% below a clinically acceptable threshold, which is set at 20%. Under the null hypothesis, this design with an alpha of 0.05 and power of 80% results in an expected number of cases of 30. In our validation cohort we assume that around 3% of patients will have grade 3 long-term urogenital toxicity (i.e. 2 patients). The rate of treatment discontinuation within 3 months is considered negligible. Our aim is to show with high probability, that the event rate is below a clinically acceptable threshold, which is set at 12%. Under the null hypothesis, this design with an alpha of 0.05 and power of 80% results in an expected number of cases of 75.
Interventions
- Radiation radiotherapy
Patients with prostate cancer in the medium or high risk range who are planned to receive definitive CT or MRI-adaptive SBRT.
Primary outcome measures
- acute grade ≥ III urogenital toxicity [Time frame: ≤ 3 months after completion of radiotherapy]
Secondary outcome measures (9)
- Gastrointestinal toxicity of grade ≥3 [Time frame: ≤ 3 months after completion of radiotherapy]
- Mortality [Time frame: ≤1 year after initiation of radiotherapy]
- Urogenital and gastrointestinal toxicities [Time frame: ≤ 5 years after completion of radiotherapy]
- Biochemical progression-free survival [Time frame: ≤ 5 years after completion of radiotherapy]
- Hormonal therapy-free survival [Time frame: ≤ 5 years after completion of radiotherapy]
- Overall survival [Time frame: 5 years after completion of radiotherapy]
- Quality-of-life questionnaire C-30 from the European Organisation for Research and Treatment of Cancer [Time frame: ≤ 5 years after completion of radiotherapy]
- Uroflowmetry (optional) [Time frame: Uroflowmetry ≤ 6 weeks prior to the start of radiotherapy]
- Quality-of-life questionnaire PR25 of the European Organisation for Research and Treatment of Cancer [Time frame: ≤ 5 years after completion of radiotherapy]
Eligibility criteria
Inclusion criteria
- histologically confirmed localized prostate cancer
- planned treatment is SBRT according to standard of care and consists of definitive CT or MRI online adaptive SBRT of the prostate according to the PACE trial which includes a total dose to clinical target volume 1 (CTV1, i.e. prostate and proximal 1 cm of the seminal vesicle) of 40.0 Gy in 5 weekly fractions (single dose of 8.0 Gy) and total dose to planning target volume 1 (PTV1) of 37.5 Gy in 5 weekly fractions (single dose of 7.5 Gy) with a compromise for bowel sparing allowed. For patients with unfavorable intermediate to very high-risk disease (according to NCCN guidelines) a total dose to the planning target volume 2 (PTV2, i.e. proximal 1-2 cm of the seminal vesicle) of 32.5 Gy in 5 weekly fractions (single dose of 6.5 Gy) will be delivered.
- intermediate to (very) high risk localized prostate cancer (≤ cT3a and Gleason score ≤ 9 and/or PSA ≤ 20 ng/ml)
- prostate volume > 60 cc and/or IPSS > 12;
Exclusion criteria
- Very high risk localized prostate cancer with indication for ADT and ARPI (i.e. Gleason ≥ 8 and cT3a)
- Involvement of seminal vesicles (cT3b)
- Contraindications against definitive CT or MRI-adaptive radiotherapy of the prostate, e.g. inflammatory bowel disease (IBD); previous radiotherapy in the pelvis, previous local radiotherapy of the prostate, contraindication for MRI or CT;
- Patients with severe genitourinary symptoms (e.g. recent urinary retention ≥ grade 3 according CTCAE v.5.0);
- Lymph node metastases or distant metastases (i.e. no localised prostate cancer);
- Participation in a clinical trial which might influence the results of this project.
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Case-only
Study locations
Germany · 2 centers
- Klinik für Radioonkologie und Strahlentherapie, Universitätsklinikum Heidelberg — Heidelberg
- Klinik und Poliklinik für Strahlentherapie und Radioonkologie, Universitätsklinikum LMU — Munich
Switzerland · 1 center
- University Hospital Zurich, Department of Radio-Oncology — Zurich
Publications
- Kroese T, Andratschke N, Belka C, Corradini S, Marschner S, Liermann J, Horner-Rieber J, Fink C, Debus J, Silvia F, Tanadini-Lang S, Pouymayou B, Mencarelli A, Fesslmeier D, Schiess A, Guckenberger M, Mayinger M. Online adaptive stereotactic body radiotherapy for localized prostate cancer in patients with lower urinary tract symptoms and/or prostate hyperplasia (X-SMILE). Radiat Oncol. 2025 May 28 PMID 40437508
Identifiers
NCT: NCT06834152 · RAO-24-014