PHSOR07 Presentation Time: 9:30 AM

Abstract

Purpose

Radiotherapy for locally advanced cervical cancer (LACC) according to Embrace-II consists of EBRT and image guided adaptive intracavitary/interstitial BT. BT for LACC is known to be a complex and time consuming procedure. To speed up the process, we developed BiCycle for fast and automated treatment planning. In retrospective and prospective validations, BiCycle resulted in more consistent and often superior treatment plan quality and significant decrease in planning time [Radiother Oncol 148(143), 2020; 170(S390), 2022; 182(S92), 2023]. The European Medical Device Regulation (MDR) has been applicable since May 26, 2021. Its main aim is to ensure safety and effectiveness of medical devices. The purpose here is to describe key elements of the conversion of BiCycle as a research tool into an MDR-compliant medical device.

Materials and Methods

BiCycle was implemented as an add-on to our current clinical commercial TPS. Implant reconstruction and target- and OAR delineation are performed in the commercial system and then exported to BiCycle, which optimizes the dwell times, that are subsequently imported in the commercial TPS to calculate the final dose distribution. After regular QA by the multidisciplinary team, the plan is sent to the afterloader and used for treatment. MDR article 5(5) enables health institutions to use in-house developed medical devices, provided that, among others, the following conditions are met. The health institution: 1) Justifies in its documentation that the target patient group's specific needs cannot be met by an equivalent device available on the market; 2) Draws up documentation that makes it possible to have an understanding of the manufacturing facility and -process, design and performance data of the device, including the intended purpose, and that is sufficiently detailed to enable the competent authority to ascertain that the general safety and performance requirements are met; 3) Implements and maintains an appropriate Quality Management System (QMS) to control manufacturing and use of the device; 4) Reviews experience gained from clinical use of the device and takes all necessary corrective actions.

Results

Clinical implementation and documentation of BiCycle according to MDR lasted ∼12 months. 1) Consultation of the market revealed that none of the commercially available TPS fulfilled all performance requirements (i.e. fully automated and non-inferior). 2) Software development was supported by the Redmine issue tracking system (https://www.redmine.org/). Issue types were organized in a hierarchical way so that development activities were linked to requirements. Requirements were represented by parent issues, and corresponding programming, configuration, regression and acceptance testing issues were added as child issues. Changes to the source code were tracked by the software versioning system Subversion (https://subversion.apache.org/). Redmine and Subversion systems were linked by obligatory issue ID added to each modification to the Subversion repository. This procedure ensures structured coupling between the code and product requirements. A heterogeneous dataset of 82 plans was built and used to verify performance by comparison to previously validated results. Safety requirements were verified using a risk analysis and end-to-end test. The latter revealed no measured dose differences between a delivered BiCycle plan and a manual plan with equal dwell positions/times as the BiCycle plan. 3) All documentation was stored in our institution's QMS and is readily available to the competent authority. 4) Since clinical introduction on August 15, 2023, prospective data are collected to keep track of the clinical experience. In line with MDR, this has already resulted in several requests for system adaptations.

Conclusions

The in-house developed medical device software BiCycle for automated treatment planning was successfully implemented for LACC BT according to the MDR; the 1^st patient treatment was on August 15, 2023. Experience gained from clinical use is now collected and regularly reviewed as required by the MDR.