Using 3D printer technology to advance and optimize the use of bolus in the radiotherapy workflow

Abstract

Bolus is commonly used in Radiotherapy to escalate the dose to the skin surface for the treatment of shallow tumours and to improve dose uniformity in the region of irregular body contours. There are many different commercial solutions currently available, each of which has their own disadvantages as an all-round bolus solution. One solution which does not have these shortcomings is 3D printed bolus, which can be generated directly from a contoured structure drawn on the patient’s CT dataset and then printed accurately using readily available 3D printing technology. Recent advancements in 3D printing technology have resulted in printer technology and materials that can be easily integrated into the radiotherapy workflow. In our clinic, we have opted to use the 3DBolus system which integrates with our existing TPS. 3DBolus uses the contours generated during the planning process and leverages the TPS dose calculation algorithms to create custom bolus that represents the planned bolus dose distribution accurately. Our experience of integrating 3D printed bolus into our radiotherapy workflow found that 3D printed bolus offers four main advantages over traditional bolus methods. First, it conforms to difficult patient anatomy where traditional bolus would typically fail. Second, it can be quickly recreated or adapted if required using patient’s treatment imaging. Third, it offers the clinicians a consistent and accurate representation of the planned dose distribution on the treatment unit. Finally, it was found to be more efficient on the treatment units compared to current bolus techniques. Bolus is commonly used in Radiotherapy to escalate the dose to the skin surface for the treatment of shallow tumours and to improve dose uniformity in the region of irregular body contours. There are many different commercial solutions currently available, each of which has their own disadvantages as an all-round bolus solution. One solution which does not have these shortcomings is 3D printed bolus, which can be generated directly from a contoured structure drawn on the patient’s CT dataset and then printed accurately using readily available 3D printing technology. Recent advancements in 3D printing technology have resulted in printer technology and materials that can be easily integrated into the radiotherapy workflow. In our clinic, we have opted to use the 3DBolus system which integrates with our existing TPS. 3DBolus uses the contours generated during the planning process and leverages the TPS dose calculation algorithms to create custom bolus that represents the planned bolus dose distribution accurately. Our experience of integrating 3D printed bolus into our radiotherapy workflow found that 3D printed bolus offers four main advantages over traditional bolus methods. First, it conforms to difficult patient anatomy where traditional bolus would typically fail. Second, it can be quickly recreated or adapted if required using patient’s treatment imaging. Third, it offers the clinicians a consistent and accurate representation of the planned dose distribution on the treatment unit. Finally, it was found to be more efficient on the treatment units compared to current bolus techniques.