Therapeutic Benefit of Intracavitary-interstitial Brachytherapy in Cervical Cancer Patients with Small and Large High-risk Clinical Target Volume

makbule tambaş
2021 Turkish Journal of Oncology  
We aimed to investigate the added value of interstitial brachytherapy (IS-BT) over classical intracavitary BT (IC-BT) in terms of target coverage and organ at risk (OAR) sparing among patients for whom an optimal dose distribution could not be provided without IS-ICBT and also to determine if the magnitude advantage provided by IS-BT is similar in patients smaller (<30 cm 3 ) and larger (≥30 cm 3 ) high-risk clinical target volume (CTV HR ). METHODS 24 patients treated with IS-ICBT were
more » ... in this study. IS-BT was performed 76 of 93 BT fractions. For each patient, two additional IC-BT planning were created: (1) ICBT Target-focused plan: The priority was adequate coverage of CTV HR . Then, the OARs were spared as much as possible. (2) ICBT OARs-focused plan: The priority was given to the OAR sparing. Then, highest CTV HR coverage was tried to achieve within the allowed OAR dose limits. The IS-ICBT plans were compared with these two plans in terms of target coverage and OAR doses. RESULTS 13 patients had large and 11 patients had small CTV HR . In IS-ICBT plans, EQD2 10 CTV HR D90 doses were significantly higher compared with ICBT OARs-focused plans (Δdose: 10.5±6.2 Gy, p<0.001), whereas EQD2 3 OAR D2cc doses were significantly lower compared with ICBT Target-focused plans (Average Δdose, bladder: 24.5±25.9 Gy [p<0.001], rectum: 7.6±9.7 Gy [p=0.001], sigmoid: 18.3±15.3 Gy [p<0.001]). There was no significant difference between patients with small and large CTV HR in terms of ∆doses of both target and OARs. CONCLUSION IS-BT provides significant therapeutic advantage over IC-BT for patients both with small and large CTV HR .
doi:10.5505/tjo.2021.2837 fatcat:6wuxvvmw2jdszfswox4p2jkm4i