Leonid Grigorievich Sukhikh

By Evgeniia Sergeevna Sukhikh and Leonid Grigorievich Sukhikh

A dosimetric and radiobiological investigation of the possibility to replace the traditional combined radiation therapy (3D-CRT + high-dose-rate brachytherapy (HDR-BT)) of cervical cancer with the following combinations, 60Co + VMAT, 3D-CRT + VMAT, and VMAT + VMAT, without change of total course dose and the number of fractions is described. For the investigation, the data of 11 patients with a diagnosis of cervical cancer (stages T2bNxM0 and T3NxM0) who received a course of combined radiotherapy was used. The 3D-CRT + high-dose-rate brachytherapy (HDR-BT) combination of dose delivery techniques was used as the basic one. The following fractionation regimes for combined radiotherapy were simulated: external beam radiation therapy (RT) (EBRT) of the first stage, total dose 50 Gy and fractional dose 2 Gy (25 fractions), and the second stage—total dose 28 Gy and fractional dose 7 Gy (4 fractions). Total combined RT course dose amounted to EQD2 = 89.7 Gy. Simulation results show that there is a technical possibility of replacing the second stage of combined RT of cervical cancer by EBRT based on the VMAT technique. Implementation of the VMAT technique allows increasing the uniformity of irradiated volume coverage compared with traditional high-dose rate. While using the VMAT technique, the tolerant levels of organs at risk are not exceeded.

Part of the book: Gynaecological Malignancies