Image-guided Stereotactic Body Radiation Therapy in Patients with Isolated Para-aortic Lymph Node Metastases from Uterine Cervical and Corpus Cancer

Purpose: The aims of this study were to evaluate the role of stereotactic body radiation therapy (SBRT) as a local treatment for isolated para-aortic lymph node (PALN) metastases originating from uterine cervical and corpus cancer.

Methods And Materials: We retrospectively enrolled 30 patients with isolated PALN metastases originating from uterine cervical and corpus cancer who had received SBRT using the CyberKnife (CK). All patients were shown to have isolated PALN metastases by computed tomography (CT) and/or positron emission tomography (PET)-CT. The overall survival (OS), local control (LC) rate, and disease progression-free survival (DPFS) rate were calculated according to the Kaplan-Meier method. Comparison between prognosis groups was performed using log-rank analysis. Toxicities were also evaluated.

Results: The 4-year OS rate was 50.1%, and the median survival time was not reached. The OS rate among symptomatic patients was significantly lower than that among asymptomatic patients (p = 0.002). The 4-year actuarial LC rate was 67.4%. Patients with a planning target volume of </=17 ml had significantly higher LC rates (p = 0.009). The 4-year DPFS rate was 45.0%, and the median time to disease progression was 32 months. Small planning target volume was a favorable prognostic factor (p = 0.043). Grade 3 or 4 complications requiring hospitalization were reported in 1 patient at 20 months after SBRT.

Conclusion: The OS and LS rates were promising, and the incidence of toxicities was low. Use of SBRT with the CyberKnife is an effective modality for treating isolated PALN metastases in patients with uterine cervical and corpus cancer.