• Półtorak, Łukasz
• Walecka, Irena
• Zimon, Damian
• Sobolewski, Piotr
• Półtorak, Michał
• Bonatkiewicz, Paweł
• Szwast, Maciej

Abstract

Brachytherapy is a type of radiation therapy, in which a radiation source is placed directly or close to a tumor.It is commonly used to treat skin cancer, and enables precise irradiation treatment of affected area (planning target vol-ume – PTV) while minimizing exposure dose to surrounding healthy tissue (organs at risk – OARs). Recently, the useof 3D printing has begun revolutionizing brachytherapy, as it allows manufacturing of custom-designed applicatorsfor unique shape of skin topography, tumor, and surrounding tissues. Outcome of the combination of 3D printing andbrachytherapy has several advantages over traditional treatment planning methods. Some of the advantages are intu-itive, whereas others can be concluded from a literature overview as follows: 1) Possibility of developing patient-spe-cific applicators that precisely match the shape of tumor area; 2) Reduction of the time required for applicator produc-tion, especially when custom-made devices are needed; 3) Reduction of manufacturing costs; 4) Treatment proceduresimprovement; 5) Improvement of safety measures accelerated by the development of smart materials (e.g., polymerfilaments with admixture of heavy elements); 6) Possibility of nearly instant adjustment into tumor treatment (appli-cators can be changed as the tumor is changing its shape); and 7) Applicators designed to securely fit to treatment areato hold radioactive source always in the same place for each fraction. Consequently, tumor-provided dose is accurateand leads to effective treatment. In this review paper, we investigated the current state-of-the-art of the application of3D printing in brachytherapy. A number of existing reports were chosen and reviewed in terms of printing technology,materials used, treatment effectiveness, and fabrication protocols. Furthermore, the development of future directionsthat should be considered by collaborative teams bridging different fields of science, such as medicine, physics, chem-istry, and material science were summarized. With the indicated topics, we hope to stimulate the innovative progressof 3D printing technology in brachytherapy.

Topics

• impedance spectroscopy