Objective The objective of this systematic review was to assess the oncologic outcomes of patients with International Federation of Gynecology and Obstetrics (FIGO) 2018 stage IVB cervical cancer receiving definitive pelvic radiotherapy compared with systemic chemotherapy (with or without palliative pelvic radiotherapy).

Methods This study was registered in PROSPERO (registration number CRD42022333433). A systematic literature review was conducted following the MOOSE checklist. MEDLINE (through Ovid), Embase, and Cochrane Central Register of Controlled Trials were searched from inception until August 2022. The inclusion criteria were patients with metastatic FIGO 2018 stage IVB cervical cancer, a histologic subtype of squamous cell carcinoma, adenocarcinoma, or adenosquamous carcinoma that received definitive pelvic radiotherapy (≥45 Gy) as part of management compared with systemic chemotherapy with or without palliative (30 Gy) pelvic radiotherapy. Randomized controlled trials and observational studies with two arms of comparison were considered.

Results The search identified 4653 articles; 26 studies were considered potentially eligible after removing duplicates, and 8 met the selection criteria. In total, 2424 patients were included. There were 1357 and 1067 patients in the definitive radiotherapy and chemotherapy groups, respectively. All included studies were retrospective cohort studies, and two were database population studies. The median overall survival reported in seven studies for the definitive radiotherapy arm versus systemic chemotherapy groups were 63.7 months versus 18.4 months (p<0.01), 14 months versus 16 months (p value not reported), 17.6 months versus 10.6 months (p<0.01), 32 months versus 24 months (p<0.01), 17.3 months versus 10 months (p<0.01), and 41.6 months versus 17.6 months (p<0.01), and not reached versus 19 months (p=0.13) respectively, favoring the groups that received definitive pelvic radiotherapy. The high clinical heterogeneity precluded the performance of meta-analysis, and all studies were at serious risk of bias.

Conclusions Definitive pelvic radiotherapy as part of treatment in patients with stage IVB cervical cancer may improve oncologic outcomes compared with systemic chemotherapy (with or without palliative radiotherapy); however, this is based on low-quality data. Prospective evaluation would be ideal before the adoption of this intervention in standard clinical practice.