The Use of 3D Printing Technology in Gynaecological Brachytherapy—A Narrative Review.

Simple Summary: Cervical and endometrial cancers are the fourth and sixth most common cancers in women, respectively. Radiation therapy, including brachytherapy, is an important component of their treatment. Commercially available brachytherapy applicators only come in limited sizes and designs and either do not fit in some patients or do not allow adequate dose delivery to the target volume. In recent years, customised 3D-printed applicators have been increasingly used in such cases. This review summarises the role of 3D printing in brachytherapy of gynaecological tumours. Radiation therapy, including image-guided adaptive brachytherapy based on magnetic resonance imaging, is the standard of care in locally advanced cervical and vaginal cancer and part of the treatment in other primary and recurrent gynaecological tumours. Tumour control probability increases with dose and brachytherapy is the optimal technique to increase the dose to the target volume while maintaining dose constraints to organs at risk. The use of interstitial needles is now one of the quality indicators for cervical cancer brachytherapy and needles should optimally be used in ≥60% of patients. Commercially available applicators sometimes cannot be used because of anatomical barriers or do not allow adequate target volume coverage due to tumour size or topography. Over the last five to ten years, 3D printing has been increasingly used for manufacturing of customised applicators in brachytherapy, with gynaecological tumours being the most common indication. We present the rationale, techniques and current clinical evidence for the use of 3D-printed applicators in gynaecological brachytherapy. [ABSTRACT FROM AUTHOR]