The use of 3D computer-aided design to optimize photoimmunotherapy catheter placement

Abstract

Background

There is limited information regarding how technical aspects of Photoimmunotherapy (PIT) catheter placement influences outcomes. We hypothesize that optimized 3D models of PIT treatment will demonstrate a higher volume of tumor treated compared to 3D models of actual intraoperative catheter placement.

Methods

Clinical and radiographic data were obtained for RM-1929 photoimmunotherapy treated patients at a single institution from March 2016 to August 2021. 3D models were rendered to recreate photoimmunotherapy treatments based on intraoperative images. This was compared to an optimized therapy model for each instance of treatment. Comparisons were made between actual and optimized models based on total volume of tumor treated as well as number of cylindrical diffusers placed per treatment.

Results

3D models were generated for 9 PIT treatments in 6 patients. Optimized PIT models (N = 9) were matched and compared to actual PIT models (N = 9). Volume of tumor treated was higher for the optimized model compared to the actual treatment (22.6 vs 13.9 cm³, p = 0.004) with a higher percentage of total tumor volume treated (92.1 % vs 69.0 %, p = 0.004). Approximately 2.8 additional LF diffusors were placed per treatment in the optimized plan (8.0 vs. 5.2, p = 0.033).

Conclusion

In this post-hoc analysis, we demonstrate the importance of appropriate catheter placement in PIT as well as the feasibility of 3D computer aided design to simulate PIT catheter placement. Optimized 3D models demonstrated a higher volume of tumor treated compared to actual catheter placement. 3D computer aided design may be a useful adjunct to preoperative planning to optimize PIT catheter placement.