The following is a summary of “Factors affecting D90 High-risk Clinical Target Volumes (HR-CTV dose) of intracavitary and interstitial brachytherapy in locally advanced cervical cancer,” published in the November 2024 issue of Oncology by Chitmanee et al.
People with locally advanced cervical cancer benefit from intracavitary (IC) and interstitial (IS) brachytherapy to improve high-risk clinical target volume (HR-CTV) dose coverage, as guided by the GEC-European Society for Radiotherapy and Oncology (GEC-ESTRO) guidelines.
Researchers conducted a retrospective study to identify factors affecting D90 HR-CTV dose and to evaluate related clinical outcomes in people undergoing brachytherapy for cervical cancer.
They analyzed data from 424 individuals with cervical cancer (FIGO stage IB1 to IVA) treated with chemoradiation and high-dose-rate brachytherapy (2014 and 2023). Dose coverage of HR-CTV (D90 ≥ 85 Gy in equivalent dose in 2 Gy fractions [EQD2]) was assessed based on implantation type, tumor size, lateral extension, and HR-CTV volume.
The results showed that 86.8% of individuals achieved a D90 HR-CTV dose of at least 85 Gy in EQD2. Both IC/IS brachytherapy and HR-CTV volume were significant factors in achieving this dose (P=0.012 and P=0.000, respectively). For HR-CTV volumes greater than 35 ml, IC/IS brachytherapy was associated with achieving the target dose (P=0.017). Local control rates were 72.08% for HR-CTV volumes smaller than 20 cm3, 68.42% for 21-30 cm3, 71.68% for 31-60 cm3, and 17.67% for volumes greater than 60 cm3 (P=0.005). Grade 3 toxicities included proctitis (7.1%), cystitis (1.9%), and vaginal stenosis (0.2%).
They concluded that IC/IS brachytherapy helped people with HR-CTV volumes greater than 35 ml achieve D90 HR-CTV doses of at least 85 Gy in EQD2, with favorable local control rates and low toxicity levels.
Source: sciencedirect.com/science/article/abs/pii/S0936655524005004
