The impact of volumetric modulated arc radiotherapy on clinical outcomes of patients with gynecological malignancies

Abstract

Introduction. In locally advanced cancers of the cervix, endometrium and vulva, radiotherapy is the primary treatment modality. In recent years, new modern techniques of external radiation have been developed in radiation oncology, with the goal of dose escalation to the target volume, while sparing healthy tissues. The aim of this study is to determine the impact of volumetric modulated arc therapy on clinical outcomes of patients with gynecological malignancies. Material and Methods. Data were retrospectively collected from 60 patients treated for International Federation of Gynecology and Obstetrics stage I - III cervical, endometrial and vulvar cancers, using definitive (n = 35) or adjuvant (n = 25) radiotherapy/ chemoradiotherapy. Thirty patients underwent three-dimensional conformal radiation therapy (definitive in 22 and adjuvant in 8) and the other 30 patients were treated with volumetric modulated arc therapy (definitive in 13 and adjuvant in 17). The following clinical outcome parameters were compared between the two groups: complete clinical response, disease free survival, progression free survival, and 4-year overall survival. Results. Progression free survival of patients treated with definitive radiotherapy/ chemoradiotherapy using volumetric modulated arc therapy was 17.2 months, while in the group treated with three-dimensional conformal radiation therapy it was 7.9 months (p = 0.300). Four-year overall survival in patients who were treated with definitive radiotherapy/ chemoradiotherapy using three-dimensional conformal radiation therapy was 50%, and 61.5% in the group treated with definitive volumetric modulated arc therapy (p = 0.200), while in patients treated using adjuvant radiotherapy/chemoradiotherapy it was 75% vs. 88.2%, respectively (p = 0.400). Conclusion. Although without statistical significance, volumetric modulated arc therapy showed better results with respect to progression free survival and 4-year overall survival in previously unoperated patients who underwent definitive radiotherapy/chemoradiotherapy.