OBJECTIVETo compare the efficacy of methylene blue versus carbon nanopartIcles suspension injection as a tracer for sentinel lymph node detection in breast cancer and the factors associated with the definition of sentinel lymph node biopsy.

METHODSOne hundred and sixteen patients with early breast cancer underwent intraoperative sentinel lymph node biopsy, among them 51 patients accepted injection of methylene blue dye, while 65 patients received carbon nanopartIcles suspension injection. The mapping procedures and SLNB were performed using subareolar or peritumoral injection of methylene blue or carbon nanopartIcles suspension injection at the site of the primary breast cancer, followed by the axi11ary lymph node dissection (ALND). All the SLN and ALN were evaluated pathologically post-operatively.

RESULTSIn the MB group, the false-negative, sensitivity, accuracy, specificity rate of SLNB detection were 88.2%, 13.3%, 86.7%, 84.3%, and 100%, respectively. In the CNP group, the false-negative, sensitivity, accuracy, specificity rate of SLNB detection were 98.5%, 8.7%, 91.3%, 95.4%, and 100%, respectively. The false-negative, sensitivity, specificity rate in the CNP group were trended to be higher than those in the MB group, but the difference of the accuracy and detection rates are significant (P < 0.05).

CONCLUSIONSCompared with methylene blue solution, the carbon nanoparticle injection shows a better stability and operability for the sentinel lymph node detection in breast cancers.