Sentinel lymph node detection in early-stage ovarian cancer: a systematic review and meta-analysis

BackgroundA systematic pelvic and para-aortic lymphadenectomy remains the surgical standard management of early-stage epithelial ovarian cancer. Sentinel lymph node mapping is being investigated as an alternative procedure; however, data reporting sentinel lymph node performance are heterogeneous and limited. ObjectiveA systematic pelvic and para-aortic lymphadenectomy remains the surgical standard management of early-stage epithelial ovarian cancer. Sentinel lymph node mapping is being investigated as an alternative procedure; however, data reporting on the sentinel lymph node performance are heterogeneous and limited. This study aimed to evaluate the detection rate and diagnostic accuracy of sentinel lymph node mapping in patients with early-stage ovarian cancer. MethodsA systematic search was conducted in Medline (through PubMed), Embase, Scopus, and the Cochrane Library. We included patients with clinical stage I-II ovarian cancer undergoing a sentinel lymph node biopsy and a pelvic and para-aortic lymphadenectomy as a reference standard. We conducted a meta-analysis for the detection rates and measures of diagnostic accuracy and assessed the risk of bias using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. The study was registered in the International Prospective Register of Systematic Reviews (PROSPERO) with identifying number CRD42022351497. ResultsAfter duplicate removal, we identified 540 studies, 18 were assessed for eligibility, and nine studies including 113 patients were analyzed. The pooled detection rates were 93.3% per patient (95% CI 77.8% to 100%; I-2=74.3%, p<0.0001), and the sentinel lymph node technique correctly identified 11 of 12 patients with lymph node metastases, with a negative predictive value per patient of 100% (95% CI 97.6% to 100%; I-2=0%). The combination of indocyanine green and Tc-99m-albumin nanocolloid had the best detection rate (100% (95% CI 94% to 100%; I-2=0%)) when injected into the utero-ovarian and infundibulo-pelvic ligaments. ConclusionSentinel lymph node biopsy in early-stage ovarian cancer showed a high detection rate and negative predictive value. The utero-ovarian and infundibulo-pelvic injection using the indocyanine green and technetium-99 combination could increase sentinel lymph node detection rates. However, given the limited quality of evidence and the small number of reports, results from ongoing trials are awaited before its implementation in routine clinical practice.