Development and Preliminary Dosimetric Evaluation of a 3D-Printed Custom Tissue Compensator for Head and Neck Cancer Radiotherapy: A Proof-of-Concept Case Series
Chuxiang Jian, Xiang Xia, Jiazhou Wang, Chenlu Lian, Xuexue Cao, Ping Zhou, Dayu Xu, Qian Wu, Chengrun DuIntroduction
Achieving an optimal therapeutic ratio in head and neck cancer (HNC) radiotherapy requires balancing dose conformity with organ-at-risk (OAR) sparing. Traditional auxiliary devices often lack the customized geometry needed for modern techniques. This study developed and evaluated a 3D-printed integrated tissue compensator that serves as both a positioning stent for OAR displacement and a conformal bolus for dose build-up.
Methods
In this case series, five HNC patients (including floor of mouth, tongue, and nasal cavity and sinus cancers) were prospectively and consecutively enrolled, and their computed tomography (CT) data were used to fabricate the compensators. Dosimetric comparisons were conducted between the 3D-printed compensator, a simulated air cavity, and a conventional bite block.
Results
The integrated device demonstrated adequate geometric fidelity, maintaining random translational setup errors (σ) at ≤ 1.34 mm, comparable to traditional immobilization. Compared to the conventional group, the device demonstrated a numerical reduction in the maximum dose to the hard palate and the mean dose to the external surface, while ensuring effective dose build-up in the target region. Compared with the air cavity group, the observed numerical reductions in dose for key OARs (oral cavity, mandible, and parotid gland) approached but did not reach conventional statistical significance (p = 0.063). Furthermore, the device maintained comparable conformity (CI) and homogeneity (HI) indices, showing an observed numerical improvement in homogeneity for high-dose targets.
Conclusion
This feasibility study demonstrates that a 3D-printed integrated tissue compensator offers potential dosimetric advantages over conventional approaches. By maintaining setup reproducibility and OAR sparing, this device represents a practical exploratory tool for HNC radiotherapy.