Development of 3D-Printed Heterogeneous Tumour Model for Quantitative Analysis in PET/CT Imaging
The project focused on developing a tumour model using SolidWorks and 3D printing. The model was used for quantitative analysis with PET/CT imaging and the accuracy of the imaging modality in characterizing tumour heterogeneity was determined.
Tumours are heterogenous growths that consists of different types of cells with varying genetic expressions. The complex structure of the tumour makes cancer treatment difficult due to the heterogeneity of each of the cancer cells that react differently to radiation treatment. Therefore, effective treatment requires proper characterization of the tumour heterogeneity, which is limited due to the small scale of tumours that are difficult to be detected by current technologies. The purpose of this research paper was to develop a 3D printed heterogenous tumour model with multiple compartments to simulate tumour heterogeneity and to assess the accuracy of the tumour characterization in Positron Emission Tomography - Computed Tomography (PET/CT) imaging. The tumour model, known an imaging phantom was designed and modelled using SolidWorks and then constructed using the fused deposition modelling (FDM) method of 3D printing with polylactide (PLA) filament as the material. The model was then filled with radioactive imaging fluids of varying activity inside different compartments and placed under a PET/CT scanner, after which the activity was determined quantitatively using the Standard Uptake Values (SUV) of each compartment. The calculated SUV of each compartment was compared to the actual volume and activity injected which allowed us to evaluate the accuracy of the imaging modality in characterizing tumour heterogeneity. The designed imaging phantom was successful in simulating tumour heterogeneity and clear visual differences in each compartment due to the different activity was observed, albeit with some difficulty for activity under 100 µCi. Further research is required to improve the design of the phantom to allow for easier injection process of the radioactive material as well as altering the dimensions of the internal compartments to better characterize actual tumour parameters.