ABSTRACT
BACKGROUND: Tumor positivity and upstaging rates from various surgical staging steps performed in clinically early-stage epithelial ovarian carcinoma (EOC) vary widely in literature. AIM: To quantify tumor positivity and upstaging rates for all staging surgery steps in EOC patients. Differences between subgroups based on their clinical and histological characteristics are explored. METHODS: A systematic search using synonyms of 'ovarian cancer', 'neoplasm staging', and 'neoplasm metastasis' was conducted in PubMed, Embase, and the Cochrane Library. Meta-analysis was performed on 23 included studies, comprising 5194 clinical stage I or II EOC patients who underwent comprehensive surgical staging. Studies were assessed using the Newcastle-Ottawa Scale risk-of-bias tool. Pooled proportions and 95% confidence intervals were calculated using an inverse variance weighted random-effects model. RESULTS: Overall upstaging rate of clinically early-stage EOC patients was 18.7% (95%CI: 14.1-23.4%). Serous histology or high grade EOC showed the highest upstaging rate at 35.3% (95%CI: 21.8-48.7%) and 40.9% (95%CI: 35.6-46.2%). Lymph node involvement resulted in an upstaging rate of 8.7% (95%CI: 6.2-11.3%). Tumor was identified in uterus, cytology, peritoneal biopsies, omentum and appendix in 6.2% (95%CI: 1.8-10.7%), 18.4% (95%CI: 13.8-22.9%), 9.7% (95%CI: 3.8-15.6%), 5.2% (95%CI: 1.7-8.8%) and 3.6% (95%CI: 0.0-7.5%) of EOC patients. The corresponding upstaging rates were 5.9% (95%CI: 1.4-10.4%), 8.5% (95%CI: 1.8-15.2%), 3.5% (95%CI: 1.0-6.0%), 3.9% (95%CI: 1.4-6.3%) and 1.6% (95%CI: 0.0-3.4%), respectively. CONCLUSION: The attributive value of comprehensive surgical staging in clinically early-stage EOC patients remains substantial, particularly in serous and high grade tumors.