Definitive irradiation as a first treatment strategy for primary and metastatic sites of newly diagnosed IVB cervical cancer that presented with synchronous oligometastases

BACKGROUND: The present study identified survival and progression-free rates and evaluated prognostic factors for IVB stage cervical cancer in patients that presented with synchronous oligometastases (sync-oligometastases) who received definitive irradiation for primary and metastatic sites. METHODS: The study retrospectively included 60 patients with newly diagnosed stage IVB cervical cancer. Patients received definitive radiation for both primary and metastatic sites through Volumetric Modulated Arc Therapy (VMAT) or intensity modulated radiation therapy (IMRT) followed by three dimensional-intracavitary/interstitial brachytherapy at our institution between July 2014 to December 2020. All patients were staged based on the International Federation of Gynecology and Obstetrics (FIGO) 2018 guidelines. Overall survival (OS), progression-free survival (PFS), and patient prognostic factors were analyzed. RESULTS: The 60 patients who received curative-intent irradiation for primary and metastatic sites showed a 5-year OS rate of 51.4% and a 5-year PFS rate of 25.9%. The median PFS was 52.3 months, and the median OS had not been reached. Lymphatic metastases had a better OS compared with hematogenous metastases (3-year OS rates: 57.2% vs. 20%, p = 0.017). Patients with one metastasis site showed a more favorable prognosis than patients with ≥ 2 metastases sites (3-year OS rates: 60.4% vs. 20.6%, p = 0.003). Patients that presented with tumors larger than 4 cm in diameter before treatment demonstrated a poorer prognosis (5-year OS rates: 41.2% vs. 65.2%, p = 0.029; 5-year PFS rates: 10.4% vs. 53.7%, p = 0.021). CONCLUSION: Definitive irradiation for both primary and oligo-metastatic sites for selected IVB patients is a feasible treatment strategy. Metastatic type, number of metastatic sites, and pre-treatment tumor diameter were significant prognostic factors. Neoadjuvant chemotherapy, the lymph nodal metastatic type (supraclavicular or inguinal), and number of lymphatic metastatic sites failed to reach statistical significance as prognostic factors.