Multi-target Tracking in Prostate Radiotherapy Using MLC and KIM

Not Applicable

Withdrawn

• Conditions: Prostate Cancer
• Interventions: Device: Combined real-time use of 'Multi-Leaf Collimator Adaptation' and 'kV Intrafraction Monitoring'

• Registration Number: NCT02588846
• Lead Sponsor: Royal North Shore Hospital

Brief Summary

Assessing the feasibility of implementing real-time multi-leaf collimator (MLC) tracking to account for the relative motion of the moving prostate tumour target and the static pelvic nodal target for high-risk prostate cancer patients. The capability of tracking for the relative motion of multiple targets will ensure that all the treatment targets receive correct dose as prescribed by the doctor and minimise side effects to the critical organs.

Detailed Description

This study will assess the feasibility of implementing real-time multi-leaf collimator (MLC) tracking to account for the relative motion of the moving prostate tumour target and the static pelvic nodal target for high-risk prostate cancer patients. The capability of tracking for the relative motion of multiple targets will ensure that all the treatment targets receive correct dose as prescribed by the doctor and minimising side effects to the critical organs.

During radiation treatment, the prostate position will be monitored in real time using the KIM technology. The nodal target will be imaged before and after each treatment to evaluate the nodal treatment margin. The MLC tracking is implemented by recalculating the radiation beam shape fit for the moved prostate and static nodal targets and sending the adjusted MLC leaf positions to the treatment delivery system. The actually delivered dose to the patient will be calculated after the treatment and compared to the dose without MLC tracking to assess the treatment efficacy.

Study Timeline

• Study First Submitted: 2015-07-14
• Study First Submitted QC: 2015-10-26
• Study First Posted: 2015-10-28
• Study Start: 2024-10-03
• Primary Completion: 2024-10-03
• Study Completion: 2024-10-03
• Status Verified: 2024-11
• Last Update Submitted: 2024-11-14
• Last Update Posted: 2024-11-18

Recruitment & Eligibility

• Status: WITHDRAWN
• Sex: Male
• Target Recruitment: Not specified

Inclusion Criteria

• Patients undergoing definitive external beam radiotherapy at Northern Sydney Cancer Centre
• Patients histologically proven prostate adenocarcinoma
• PSA obtained within 3 months prior to enrolment
• Pelvic lymph nodes are included for treatment for patients at stage T1c-T3b with Gleason 8-10 or prostate-specific antigen (PSA) > 20 ng/ml or pelvic lymph node positivity on conventional imaging or prostate-specific membrane antigen (PSMA) scans.
• Patient must be able to have gold fiducial markers placed in the prostate
• Eastern Cooperative Oncology Group (ECOG) performance status 0-2
• Ability to understand and the willingness to sign a written informed consent document.
• Prostate dimension that allows leaf span with tracking margin of ±8mm

Exclusion Criteria

• Patients with artificial Hip(s), lumbar spinal surgical rods or other large metallic pelvic implants
• Patient's dimensions >40cm as measured at the level of the prostate
• Patients with overlapping implanted gold fiducials in x-ray imaging

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Stage 1: Optimise nodal treatment margin	Combined real-time use of 'Multi-Leaf Collimator Adaptation' and 'kV Intrafraction Monitoring'	During Stage 1: Optimise nodal treatment margin, Combined real-time use of 'Multi-Leaf Collimator Adaptation' and 'kV Intrafraction Monitoring' will be used to reshape the radiation beam in real-time. The nodal target position stability will be evaluated by the cone beam computed tomography (CBCT) imaging before and after each treatment session for the first 10 patients.
Stage 2: Use treatment margin	Combined real-time use of 'Multi-Leaf Collimator Adaptation' and 'kV Intrafraction Monitoring'	During Stage 2: Use treatment margin, Combined real-time use of 'Multi-Leaf Collimator Adaptation' and 'kV Intrafraction Monitoring' will be used to reshape the radiation beam in real-time. At the same time, multi-leaf collimator (MLC) tracking will be used to reshape the radiation beam in real-time using the margin size determined in Stage 1.

Primary Outcome Measures

Name	Time	Method
Software or mechanical failure	The treatment period (2-9 weeks)	The percentage of fractions delivered without software or mechanical failure

Secondary Outcome Measures

Name	Time	Method
Dosimetric accuracy	Treatment period (2-9 weeks)	The estimated dose distributions will be compared to the original plan using the dose reconstruction method18 based on the prostate motion trajectory and the logged MLC positions (beam shapes).
Geometric accuracy	The treatment period (2-9 weeks)	The geometric accuracy of the beam shape, determined by comparing the ideal beam shape with the actual beam shape.
Prostate motion trajectory	Treatment period (2-9 weeks)	Prostate motion trajectory measured by KIM.
Acute toxicity	Treatment period (2-9 weeks) plus 3 months	Toxicity during treatment

Trial Locations

Locations (1)

Royal North Shore Hospital; 🇦🇺 St Leonards, New South Wales, Australia