Carbon Nanoparticles and Indocyanine Green for Sentinel Lymph Node Biopsy in Early Stage Cervical Cancer

The metastasis rate of pelvic lymph node in early cervical cancer is low. Systemic lymph node resection is traumatic and has many complications. Sentinel lymph node (SLN) biopsy can effectively avoid unnecessary lymph node dissection, which has been recommended in clinical guidelines. Indocyanine green(ICG) fluorescence imaging as the method of SLN mapping is recommended in international guidelines. However, the imaging equipment is very expensive which limits the popularization of ICG in different medical centers of various surgical volumes. Carbon nanoparticle is an innovative tracer without any special imaging equipment for SLN mapping in China. Some retrospective researches have proved that carbon nanoparticle is effective, simple, economic and suitable for popularization in different medical centers. In this study, a prospective randomized controlled trial will be conducted to analyze the non-inferiority of carbon nanoparticles compared to ICG, and to verify the application value of carbon nanoparticles. 144 cervical cancer patients with stage IB1 (FIGO2018) will be prospectively enrolled and randomly divided into two groups (R = 1:1). 72 patients will undergo SLN biopsy with carbon nanoparticles and 72 patients will be mapped by ICG. The primary endpoint is overall SLN detection rate. The secondary endpoints include bilateral SLN detection rate, the number of SLN detected, sensitivity, false negative rate and negative predictive value of SLN biopsy. Diagnostic accuracy will be evaluated at both pelvis and patient levels. What's more, SLN pathological ultrastaging will be conducted to increase the diagnostic accuracy. The hypothesis of this study is that the overall SLN detection rate by carbon nanoparticles is not inferior to that using ICG. And the differences of bilateral SLN detection rate, sensitivity, false negative rate and negative predictive value between two groups are not significant.