Evgeniia SukhikhHead of the Department of Medical Physics of Tomsk Regional Oncology Center , Russian Federation
Title: Dosimetric and Radiobiological Evaluation of Combined Radiotherapy of Cervical Cancer Based on the VMAT Technique
For some patients with locally advanced cervical cancer (LACC), the brachytherapy is not an option. The possible treatment includes two-stage external beam radiotherapy (sequential boost - SEQ) or single-stage external beam radiotherapy (simultaneous integrated boost - SIB). The single-stage SIB-VMAT (25,27 or 30 fractions) and double-stage SEQ-VMAT (25+6 fractions) plans were developed to deliver EQD2=50Gy to the pelvic region and EQD2=90Gy to the tumour. The developed plans were compared with respect to EQD2 dose delivered to tumour and to the OARs, expected tumour control probability and normal tissue complications probability.
The developed SIB-VMAT and SEQ-VMAT plans had the physical coverage of the CTV tumours more than 95% of prescribed dose delivered to more than 95% of the volume. The irradiation of the tumour for both SIB-VMAT and SEQ-VMAT has comparable EQD2 values close to 87-88 Gy. SIB-VMAT treatment plans provided lower levels of OARs irradiation than SEQ-VMAT plans. The optimal number of fractions for SIB-VMAT was equal to 27.
In conclusion, SIB-VMAT is better treatment technique for the patients with LACC with brachytherapy impossibility. Results show that both SIB-VMAT and SEQ-VMAT allowed good coverage of the tumour and high-quality dose delivery. SIB-VMAT allowed to minimize OARs irradiation and to save at least a week of overall treatment time.
Evgeniia Sukhikh has completed her PhD at the age of 28 years from Tomsk Polytechnic University, RU. ?he is the Assistant Professor at Tomsk Polytechnic University / Head of the Department of Medical Physics of Tomsk Regional Oncology Center, RU. She has over 100 publications that have been cited over 30 times, and her publication H-index is 3.