| Project Detail |
As an advanced radiotherapy technique, Proton Therapy has been treating constantly rising numbers of cancer patients worldwide, with the number of new facilities growing exponentially over the last decade. Proton Therapy intrinsically provides personalized cancer treatment, since the dose distributions are customized to the tumour location, size and shape of each patient individually, allowing to target the tumour with very high accuracy, whilst sparing the surrounding healthy tissue from unnecessary radiation delivery and potentially damage. However, Proton therapy currently has two major drawbacks. First, it is a costly treatment, as it is resource intensive and due to the size of the facilities required, with gantries for proton therapy typically having diameters of 10 meters or more. Second, the quality of the delivered treatment can be substantially affected by inter- and intra-fractional variations due to anatomic changes and organ motion. Therefore, in this project, we will investigate the feasibility of developing the tools and workflows to support an efficient 4D Adaptive Proton Therapy (4DAPT) framework, which can simultaneously mitigate the detrimental effects for Pencil Beam Scanned Proton Therapy (PBS-PT) treatment due to intra- and inter-fractional motion. In addition, we will apply these tools to an alternative method of patient positioning for therapy (i.e. vertical rather than horizontal) which potentially can significantly reduce the size, and therefore the costs of future proton therapy facilities. Two strategic working packages are proposed accordingly. First, we would like to extend our knowledge on typical patient motions and anatomical changes, by obtaining detailed insights on inter- and intra-fractional motion characteristics via longitudinal repeated 4DMR studies in both vertical and horizontal orientations of subjects (patients or volunteers). The acquired inter-fractional motion dataset will then be used to evaluate the potential degradation of current treatment regimens due to anatomical motions for patients in both orientations. Second, we would like to extend our already developed techniques of 4D and adaptive therapy by upgrading these through additionally considering deforming anatomy and dose accumulation uncertainties. For this, we will combine real-time surface motion monitoring with online image guidance to directly verify the tumour location before applying gated beam delivery. We also suggest to implement the advanced motion guided dose delivery for 4D optimized plans for increasing treatment efficiency and reducing the planning target volume. All these studies will be conducted on data generated in Work Package 1 from human subjects imaged in both vertical and horizontal orientations, and then validated experimentally using customized phantoms. We believe that the success of this project could lead to more precise, efficient and cost-effective proton treatments in the presence of both intra- and inter-fractional motion variability, and will show that 4D adaptive proton therapy could also contribute to reducing treatment costs, further broadening the indication portfolio and giving more patients the option of proton therapy. |
