Image-guided, intensity-modulated radiation therapy in definitive radiotherapy for 1433 patients with cervical cancer

Objective: Image guidance should be used for patients with cervical cancer treated with definitive intensity-modulated radiation therapy (IMRT). In this study, we provided a pattern of image guidance and verified it in a large population.

Methods: We retrospectively analyzed patients with stages IB1-IVA cervical cancer treated with IMRT combined with high-dose brachytherapy and concurrent chemotherapy in our institute from January 2005 to December 2015. A dose of 50.4 Gy in 28 fractions was prescribed to the planning target volume with fixed-field IMRT, volumetric modulated arc therapy, or helical tomotherapy. Daily megavoltage computed tomography (CT) or weekly cone-beam CT (CBCT)/CT-on-rail were used for image guidance. Considering tumor regression during treatment, a second CT simulation and IMRT planning after 20 fractions of IMRT was performed.

Results: A total of 1433 patients were included in this study. Four hundred thirteen patients (28.8%) had regional lymph node metastases. A total of 1261 patients (88.0%) received concurrent chemotherapy. The median follow-up was 32.2 months (range, 1.9-124.9 months). The 3-year overall survival (OS), disease-free survival (DFS), and local control (LC) rates were 83.0%, 75.0%, and 87.4%, respectively. The 3-year DFS rates for patients with stages IB1, IB2, IIA, IIB, IIIA, IIIB, and IVA disease were 90.2%, 87.6%, 84.0%, 76.7%, 61.6%, 59.8%, and 25.9%. The incidence rates of grade 3 or greater chronic gastrointestinal and genitourinary toxicities were 2.3% and 1.3%.

Conclusion: This pattern of image guidance was rational for patients with cervical cancer treated with IMRT. The survival rates were high, and the toxicities were acceptable.