3D-Printed Whole Prostate Models with Tumor Hotspots Using Dual-Extruder Printer.

3D printing has emerged as a popular technology in various biomedical applications. Physical models of anatomical structures concretize the digital representations and can be used for teaching and analysis. In this study we combine 3D histology with 3D printing, creating realistic physical models of tissues with hotspots of interest. As an example we use mouse prostates containing tumors. Surface meshes are created from binary masks of HE-stained serial sections of mouse prostates and manually annotated tumor areas. Sections are interpolated to expand sparse image stacks for smoother results. Fiji, Meshlab and Tinkercad are used for mesh creation and processing. Objects are printed with Prusa-based dual-extruder printer enabling different colors for tumors and the surrounding prostate tissue. Our 3D-printed mouse prostates appear realistic and tumors located at the edges of the organ are clearly visible. When transparent filament is used, the tumor hotspots are visible even when they are inside the prostate.