Karin Braide1, Ulrika Lindencrona2, Kristina Welinder3, Julia Götstedt2, Ingun Ståhl2, Niclas Pettersson2, Jon Kindblom3. 1. Dept. of Oncology, Sahlgrenska University Hospital, Gothenburg, Sweden. Electronic address: karin.braide@vgregion.se. 2. Dept. of Physics and Bioengineering, Sahlgrenska University Hospital, Gothenburg, Sweden. 3. Dept. of Oncology, Sahlgrenska University Hospital, Gothenburg, Sweden.
Abstract
PURPOSE: Three aspects of the RayPilot real-time tracking system were investigated: (1) feasibility of the transmitter with respect to implantation and explantation procedures, (2) user and patients' experiences and (3) quantification of the transmitter positional stability in relation to fiducial markers. METHODS AND MATERIALS: Ten prostate cancer patients scheduled for radiotherapy received transmitter implantation in the prostate, concomitantly with fiducial markers. Transmitter and marker positions were assessed in 3D by orthogonal kV-imaging at daily treatment setup in eight patients. RESULTS: The transmitter was successfully implanted in all patients. Patients reported mild to moderate discomfort and impact on daily activities due to the implant but overall subjective tolerability was good. One patient had spontaneous explantation of the transmitter after four fractions. One patient had transmitter 3D shifts >9 mm, but also inter-marker shifts >6 mm. The mean inter-marker shift in the remaining patients was <1 mm. In four patients, maximum transmitter 3D shifts were 5-7 mm (mean >2 mm). In three patients, mean transmitter 3D shifts were <2 mm. CONCLUSIONS: Implantation and explantation of the transmitter is generally feasible and safe. Patient tolerability is good overall. However, due to interfractional transmitter positional instability in this cohort, use of the system for real-time tracking should be combined with other daily setup techniques.
PURPOSE: Three aspects of the RayPilot real-time tracking system were investigated: (1) feasibility of the transmitter with respect to implantation and explantation procedures, (2) user and patients' experiences and (3) quantification of the transmitter positional stability in relation to fiducial markers. METHODS AND MATERIALS: Ten prostate cancerpatients scheduled for radiotherapy received transmitter implantation in the prostate, concomitantly with fiducial markers. Transmitter and marker positions were assessed in 3D by orthogonal kV-imaging at daily treatment setup in eight patients. RESULTS: The transmitter was successfully implanted in all patients. Patients reported mild to moderate discomfort and impact on daily activities due to the implant but overall subjective tolerability was good. One patient had spontaneous explantation of the transmitter after four fractions. One patient had transmitter 3D shifts >9 mm, but also inter-marker shifts >6 mm. The mean inter-marker shift in the remaining patients was <1 mm. In four patients, maximum transmitter 3D shifts were 5-7 mm (mean >2 mm). In three patients, mean transmitter 3D shifts were <2 mm. CONCLUSIONS: Implantation and explantation of the transmitter is generally feasible and safe. Patient tolerability is good overall. However, due to interfractional transmitter positional instability in this cohort, use of the system for real-time tracking should be combined with other daily setup techniques.
Authors: Denis Panizza; Valeria Faccenda; Raffaella Lucchini; Martina Camilla Daniotti; Sara Trivellato; Paolo Caricato; Valerio Pisoni; Elena De Ponti; Stefano Arcangeli Journal: Front Oncol Date: 2022-04-07 Impact factor: 5.738