Survival after sentinel lymph node biopsy for early cervical cancers: a systematic review and meta-analysis.

BACKGROUND: Sentinel lymph node biopsy represents an alternative to pelvic lymphadenectomy for lymph node staging of early-stage cervical carcinoma, but prospective evidence on long-term oncological safety of sentinel lymph node biopsy alone versus pelvic lymphadenectomy is missing. OBJECTIVE: To investigate, with this meta-analysis, the impact of sentinel lymph node biopsy alone versus pelvic lymphadenectomy on survival for patients with early-stage cervical cancer. METHODS: A systematic literature review was performed. We excluded studies in which pelvic lymphadenectomy was systematically performed after every sentinel lymph node biopsy, including only articles where pelvic lymphadenectomy was performed because sentinel lymph node biopsy was not conclusive. A meta-analysis was carried out combining 5-year disease-free survival and overall survival rates with a random and fixed effect model. Heterogeneity was tested using the Cochran Χ2 test and quantified with Higgins information I2. RESULTS: The search of databases and registers found 927 items and six articles (two retrospective and four prospective). The median time of follow-up was 34.8 months (range 13-53). Overall common effect disease-free survival was 98% while random effect disease-free survival was 94%. Overall heterogeneity was 77%. A subgroup analysis was applied, dividing studies into one group including sentinel lymph node biopsy negative data only (common effect disease-free survival 91%; random effect disease-free survival 90%), and one group with a negative and positive sentinel lymph node biopsy (common effect disease-free survival 98%; random effect disease-free survival 96%). In the analysis of overall survival, positive and negative sentinel lymph node biopsy cases were examined together (common and random effect overall survival 99%). Ultrastaging did not affect disease-free survival (common and random effect disease-free survival 92% in the ultrastaging group vs common effect disease-free survival 99% and random effect disease-free survival 96% in the non-ultrastaging group). CONCLUSIONS: Both 5-year disease-free survival and overall survival rate after sentinel lymph node biopsy alone are higher than 90% and do not differ from pelvic lymphadenectomy survival data. Ultrastaging did not impact survival.