The present disclosure is directed to a computer-implemented method for designing a patient-specific brachytherapy (BT) tandem applicator. The method is implemented using at least one processor in communication with at least one memory. The method includes receiving a radiation treatment plan for treating a region of interest. The radiation treatment plan includes a prescribed radiation dosage and patient anatomical data of the region of interested to be treated. The method also includes applying an inverse planning optimization model to determine an optimal thickness of an interior surface of the tandem applicator at a plurality of dwell positions within the region of interest. The method also includes generating a schedule of dwell times for the tandem applicator based on the generated position-dependent thickness profile. The method also includes transmitting design instructions to a 3D printer for fabrication of the tandem applicator.
