Sentinel lymph node assessment in patients with atypical endometrial hyperplasia: a systematic review and meta-analysis

ObjectiveThis systematic review and meta-analysis aimed to assess the rate of sentinel lymph node (SLN) metastases in patients with a pre-operative diagnosis of atypical hyperplasia/endometrial intra-epithelial neoplasia and endometrial cancer in hysterectomy specimens.MethodsA systematic literature review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and the protocol was registered in PROSPERO (CRD42023416769). MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Scopus databases were searched from inception until April 2023. The inclusion criteria were patients with a pre-operative diagnosis of atypical hyperplasia/endometrial intra-epithelial neoplasia undergoing hysterectomy who did or did not undergo SLN assessment.ResultsFour studies met the inclusion criteria. All studies were non-randomized studies with a total of 10 217 patients, 1044 in the SLN group and 9173 in the non-nodal assessment group. The unilateral and bilateral detection rate was 89% (I2=27.6%, 2 studies, 342 participants, 304 events) and 79% (I2=89.2%, 2 studies, 342 participants, 271 events), respectively. The rate of involved SLNs was 1.6% (I2=0%, 3 studies, 424 participants, 7 involved SLN) and 3.5% (I2=0%, 3 studies, 197 participants, 7 involved SLN) in patients with a pre-operative diagnosis of atypical hyperplasia/endometrial intra-epithelial neoplasia as the denominator and in those with endometrial cancer in the hysterectomy specimen, respectively. The cancer rate in the hysterectomy specimen was 45% (I2=72.8%, 3 studies, 503 participants, 224 events) and the most frequent endometrial cancer International Federation of Gynecology and Obstetrics 2009 stage was IA in 199 (89.2%) patients. The complication rate was similar between the groups.ConclusionThe rate of SLN metastases in patients with pre-operative atypical hyperplasia/endometrial intra-epithelial neoplasia is less than 2%, suggesting that routine SLN evaluation may not be necessary in this population.