Résumé
Objective:To compare the dosimetric difference between 3D-printed multi-channel applicator and conventional vaginal single-channel applicator for brachytherapy, aiming to provide guidance for patients receiving brachytherapy after cervical cancer surgery.Methods:From January 2019 to November 2020, 25 cervical cancer patients complicated with VAIN Ⅲ receiving 192Ir high-dose-rate brachytherapy after cervical cancer surgery were selected. Each patient was located by CT scanning with 3D-printed multi-channel applicator and conventional vaginal single-channel applicator, and corresponding plan and evaluation were carried out. The dose volume histogram (DVH) was obtained by inverse dose optimization algorithm. The dosimetric differences of high-risk clinical target volume (HRCTV), bladder and rectum during brachytherapy were compared with those of source applicators. The optimal treatment plan was selected. Results:D 90%, D 100%, V 100% and V 150% of the plans designed by 3D-printed individual multi-channel applicator had no significant differences compared with those designed by conventional single-channel applicator (all P>0.05). The bladder and rectal D 2cm 3 designed by 3D-printed multi-channel applicator were significantly lower than those using conventional single-channel applicator, and the differences were statistically significant (both P<0.05). Conclusion:The multi-channel individual applicator target made by 3D-printing technology has good conformal property, properly protects the bladder and rectum and possesses treatment advantages over conventional single-channel applicator.
Résumé
Background@#There are only very few reports on clinical outcomes using multi-channel applicators (MCA) for patients with endometrial cancer (EC) in China. We aimed to evaluate the clinical experience of treating intermediate-risk (IR) to high-risk (HR) stage I EC using in-house made multi-channel applicators (IH-MCA) in a single institution.@*Methods@#Three hundred and ninety patients with stage I IR to HR EC were treated with hysterectomy and adjuvant radiotherapy from 2003 to 2015. All patients received post-operative vaginal cuff brachytherapy (VBT) alone or as a boost after external beam radiotherapy (EBRT). The prescriptions were 500 cGy per fraction for a total of 5 to 6 fractions with brachytherapy alone or 400 to 600 cGy per fraction for 2 to 3 fractions if it was combined with EBRT. Two types of applicators including a traditional rigid IH-MCA and a recent model custom-made with 3 dimension printing technology were used for treatment. The Kaplan-Meier method was used to calculate survival rate.@*Results@#Follow-up rate was 92.8% and the median follow-up time was 48 months (range 4–172 months). The 5-year overall survival (OS), progression-free survival, local recurrence, and distant metastasis rates for all patients were 96.3%, 92.1%, 2.9%, and 4.8% respectively. Two patients had isolated relapse in vagina outside the irradiated volume. The univariate and multivariate analysis showed that age and grade were the prognostic factors correlated with OS (hazard ratio: 0.368, 95% confidence interval [CI]: 0.131–1.035, P = 0.048; hazard ratio: 0.576, 95% CI: 0.347–0.958, P = 0.026,).@*Conclusions@#For patients with IR to HR stage I EC, adjuvant VBT alone or in combination with EBRT using IH-MCA led to excellent survival and recurrence rates. Age and grade were the prognostic factors correlated with OS.