Introduction/Background To explore the clinical application of three-dimensional (3D)-printing minimally invasive-guided template in brachytherapy of patients with locally advanced cervical cancer.

Methodology From May 2016 to December 2018, 59 patients (age, 23–78 years old; median age, 57 years old) with locally advanced cervical cancer. All patients were treated with radical radiotherapy, in which external irradiation was performed, and 3D conformal and intensity-modulated radiotherapy was carried out with a radiation dose of 45 Gy in 25 fractions of 1.8 Gy per day. The included patients were randomly divided into 2 groups according to random number table method. In the template group, 29 patients assisted by 3D-printing templates to place intrauterine tubes and implant for insertion of needles. In the free implantation group, 30 patients were assisted with freehand implanted intrauterine tubes and implant needles. All patients underwent Computed Tomography (CT) to adjust the position and depth of the insertion needle, and the final CT image was transmitted to the Oncentra brachytherapy planning system, to outline the target area and organs at risk, make treatment plans, and perform treatment.

Results A total of 283 times of combination of intra-luminal and interstitial insertion radiotherapy were undertaken, and a total of 283 times of post-loading radiotherapy plan were formulated, including 141 times in template group and 142 times in free insertion radiotherapy. Complete Response (CR) rate in the template group (24/28;85.71%) was slightly higher than that in the free transplantation group (22/28; 78.57%). There was no significant difference in short-term efficacy between the two groups (z=-0.692, P>0.05). Importantly, D90 (90% of the target volume) of High-Risk Clinical Target Volume (HR-CTV) and Intermediate-Risk Clinical Target Volume (IR-CTV) in the template group were significantly higher than those in the free implantation group (t = 3.42, 2.13, P<0.05). D2 cm³ of bladder, rectum and sigmoid colon was significantly reduced (t = -2.59, -4.22, -2.01, P<0.05). Therefore, the incidence of grade 1, 2 and 3 acute radiation proctitis in the template group was noticeably lower than that in the free transplantation group (z= -2.112, P<0.05). However, there was no significant difference in the incidence of acute radioactive cystitis between the template group and the free implantation group (z=-1.686, P > 0.05).

Conclusion For large-block or eccentric cervical cancer, application of the 3D-printing minimally invasive-guided template in brachytherapy of patients with locally advanced cervical cancer can reflect its dose-based advantages, associating with a remarkable reduction of patients’ adverse reactions and a satisfactory therapeutic effect.

Disclosures None.