Global Plan Check: A Software to Register and Analyze Dose Distribution Independent from Treatment Planning Systems

Abstract

Survival of cancer patients are prolonged in the last decade. Half of the cancer patients require radiotherapy (RT) and 20% of those receive a second irradiation to the primary tumor or distant metastases. Re-irradiation of a previously irradiated region has several challenges. Total radiation dose to critical structures is the dose-limiting factor for re-RT, and for those patients who already received a curative RT already there is very small room to give an adequate dose to the target volume without violating the dose-volume constraints of normal tissues. There is a need for a software which is capable of registering various RT plans independent of the TPS used to generate the given plan. We developed a TPS-independent software to register several RT plans and project the dose distributions from these RT plans for comparison and analysis. Software was written using C## programming language and using its library for developing the dose calculation sections. Due to the need for image processing for the software, learning of the program and image analysis were evaluated with RT patient DICOM images at every step. The images, RT contours and dose data in the studied files have been analyzed and processed one by one. All data has been visualized in the program in detail and faithful to the original. A large number of patients' DICOM RT data have been analyzed for the software, and program data have been presented separately from each of them using multiple planning systems such as ECLIPSE, MONACO, VOLO. To test the reliability of the software, 20 randomly selected RT plans from different TPS have been compared in terms of mean dose, volumetric doses and DVH data. The program was able to handle the dose and contour data of RT plans in DICOM format regardless of the TPS it was generated. It has presented the data of the original plan in comparison of mean dose, volumetric dose and DVH data. The dose distributions of the previous irradiation have been shown correctly in all dose levels. All the statistical comparisons were >0,05 and we could not find any statistical difference between the original program and the developed program. Although a different planning system was used, the dose images and DHV data of the evaluated RT plans could be operated by the developed program (Figure). To our current knowledge, there is no software that offers similar features to the plan evaluation using the image processing technology that we have developed. With this evaluation system, re-RT that were treated in another center or that were planned with the old version or planning system in our clinic would be evaluated with confidence and high accuracy, and calculations problems will be minimized. We think that it will find its place as an application that will be useful for clinicians in daily practice, as re-RT and device technologies increase. So, it is possible to re-RT patients more accurately with the developed program, named 'Global Plan Check'.