A dosimetric analysis of intensity-modulated radiation therapy with bone marrow sparing for cervical cancer

Abstract

Background/aim: The purpose of the present study was to compare intensity-modulated radiation therapy (IMRT) plan with (Bone Marrow Sparing (BMS) - IMRT) or without (normal-IMRT) an intention of avoiding bone marrow in order to minimize treatment-related toxicity.

Patients and methods: Computed tomography (CT) images of 10 consecutive postoperative cervical cancer patients were used. All patients were already treated by normal-IMRT. BMS-IMRTs were created for this study and dose-volume histogram parameters were compared.

Results: Both planning target volume (PTV) D95% and D97% were statistically lower in BMS-IMRT than normal-IMRT, however, the difference was lower than 3%. There were no statistical differences between BMS-IMRT and normal-IMRT in the mean value of rectum V30Gy, V50Gy; bladder V45Gy, V50Gy; Bowel V35Gy, and V50Gy. Both in whole pelvic bone (WPB) and inner cavity of pelvic bone (ICPB), the mean value of V10Gy, V30Gy, and V40Gy of BMS-IMRT were statistically lower than that of normal-IMRT.

Conclusion: Both lower and higher dose for WPB as well as ICPB were effectively lowered by BMS-IMRT.

Keywords: Cervical cancer; IMRT; bone marrow sparing; postoperative radiation therapy; radical hysterectomy.