A Three-Dimensional-Printed Patient-Specific Phantom for External Beam Radiation Therapy of Prostate Cancer

Abstract

This paper presents the design evolution, fabrication, and testing of a novel patient and organ-specific, three-dimensional (3D)-printed phantom for external beam radiation therapy (EBRT) of prostate cancer. In contrast to those found in current practice, this phantom can be used to plan and validate treatment tailored to an individual patient. It contains a model of the prostate gland with a dominant intraprostatic lesion (DIL), seminal vesicles, urethra, ejaculatory duct, neurovascular bundles, rectal wall, and penile bulb generated from a series of combined T2-weighted/dynamic contrast-enhanced magnetic resonance (MR) images. The iterative process for designing the phantom based on user interaction and evaluation is described. Using the CyberKnife System at Boston Medical Center, a treatment plan was successfully created and delivered. Dosage delivery results were validated through gamma index calculations based on radiochromic film measurements which yielded a 99.8% passing rate. This phantom is a demonstration of a methodology for incorporating high-contrast MR imaging into computed-tomography-based radiotherapy treatment planning; moreover, it can be used to perform quality assurance (QA).

The Use of Three-dimensional Visualization Techniques for Prostate Procedures: A Systematic Review

“…Although not as robust as its development in prostate surgery, 3D visualization has also been reported in prostate radiation. Some exploratory research introduced the use of 3D printed models for dosimetric validation during stereotactic body radiation [46], guidance of radioactive seed implantation [47], and prostate external beam radiation [48]. As both imaging and radiotherapy improve, more cutting-edge techniques are expected in the field of prostate radiotherapy since it is one of the most commonly used treatment options for PCa.…”

The Role of 3D Printing in Planning Complex Medical Procedures and Training of Medical Professionals—Cross-Sectional Multispecialty Review

“…Another advantage of 3D printing is the possibility of combining different materials with different physical properties in one phantom, as was described by Hazelaar et al, They used gypsum and nylon, different dose absorbing materials, with different Hounsfield Units (HU) to develop a chest phantom closely resembling a real patient [164]. urethra, ejaculatory duct, neurovascular bundles, rectal wall, and penile bulb-all gen ated from a series of contrast-enhanced magnetic resonance images [161].…”

“…In an ideal world, phantoms should be a perfect copy of an irradiated patient, which was impossible before the era of the 3D print. Moreover, 3D printing allows for creating very complex structures, e.g., a prostate gland with an intraprostatic lesion, seminal vesicles, urethra, ejaculatory duct, neurovascular bundles, rectal wall, and penile bulb—all generated from a series of contrast-enhanced magnetic resonance images [ 161 ].…”