Use of Non-invasive 4D Ultrasound Clarity System in Prostate IMRT/RapidArc Therapy

Primarily, this is a single arm phase I study of prostate motion for prostate cancer to primarily compare prostate motion between different treatment duration for IMRT and VMAT. The radiation therapy is to be delivered using intensity modulated radiotherapy (IMRT) or Volumetric Modulated Arc therapy (VMAT) with the aid of volumetric image guidance to ensure accuracy and real-time 3D ultrasound images as observational record of the prostate motion. All the recruited patients are prescribed and treated with either VMAT or IMRT treatment. In order to simulate the behaviour of prostate motion in an IMRT scenario, the group of VMAT patients will be required to remain in treatment position for an additional 7 minutes depending on techniques used (once a week).

In order to assess the level of acceptance of the treatment position, responses to the same comfort survey for the current treatment position (i.e. using leg immobiliser) by a cohort of 60 patients treated in another IGRT treatment room will be used as the baseline. In addition, RTT satisfaction questionnaire will also be administered to assess the handling of the new immobilizer.

Acute toxicity will be measured at preset intervals using CTCAE version 3.0 and as will International prostate symptom score (IPSS) questionnaire which focuses on urinary symptoms. Symptoms or toxicities reported from this study is relevant for patients treated with IMRT or VMAT with full bladder protocol.