[Meta-analysis of application value of sentinel lymph node biopsy in early-stage vulval squamous cell carcinoma]

To systematically review the clinical value of sentinel lymph node biopsy (SLNB) in diagnosis of lymph node metastasis in early-stage squamous cell carcinoma of vulva.

Cochrane library, biomedical database (EMbase), PubMed, China national knowledge internet (CNKI), Wang Fang database, «Gynecologic Oncology», «National Medical Journal of China» and «Chinese Journal of Obstetrics and Gynecology» were searched for literatures from 1990 to 2014 concerning SLNB application in early-stage vulvar squamous cell carcinoma. Literatures were filtrated according to inclusive and exclusive criteria. Meta Disc 1.4 software was used for meta-analysis.

A total of 2 459 literatures were obtained, out of which 29 were eligible for analysis, including 28 in English and 1 in Chinese. Twenty-three studies were prospective and 6 were retrospective, including 1 371 patients with early-stage squamous cell carcinoma of vulva. The sensitivity of SLNB for diagnosis of lymph node metastasis in early-stage vulvar cancer ranged from 66.7% to 100%, and the specificity were 100% in all studies. No significant heterogeneity was found among the results of enrolled studies (I² = 12.8%, P=0.270). The data were pooled by fixed effect model, and the pooled sensitivity and specificity were 0.94 (95% CI: 0.91-0.96) and 1.00 (95% CI: 0.99-1.00), respectively. The calculated area under curve (AUC) of summarized Receiver Operating Characteristic (ROC) was 0.987 0. Subgroup analysis showed that the pooled sensitivity of SLNB were 0.92 (95% CI: 0.85-0.97) and 0.94 (95% CI: 0.91-0.97) in studies using single and combined tracers, respectively, and that they were 0.93 (95% CI: 0.90-0.96) and 0.97 (95% CI: 0.90-1.00) in studies with and without ultra-staging techniques, respectively.

SLNB is a highly accurate technique for diagnosis of lymph node metastasis in early-stage squamous cell carcinoma of vulva. The sensitivity and specificity are similar in SLNBs using different techniques.