Lymphatic Mapping, Sentinel Node Biopsy And Micrometastasis Detecting In The Patient With Breast Cancer And Their Clinical Significance

Objectives To identify the sentinel lymph nodes (SLNs) in patients with breast cancer and to demonstrate the hypothesis that the histologic characteristics of the SLN predict the histologic characteristics of remaining lymph nodes in the axilla; and study a sensitive method for the detection of breast cancer micrometastases in lymph nodes .Methods Forty-eight patients with newly diagnosed and clinical node-negative breast cancers underwent intraoperative lymphatic mapping using a patent blue alone (28 cases) and a combination of a patent blue dye and 99mTc-DX(20 cases).The SLN was identified and removed, followed by a definitive cancer operation, including a complete axillary node dissection.20 patients' micrometastases in axillary lymph nodes(including 48 SLNs and 191 NSLNs) were detected by immunohistochemical and reverse transcriptase-polymerase chain reaction(RT-PCR).Statistical analysis was performed using SPSS. Results The SLN was successfully identified in 44 of 48 patients(91.7%) using the two lymphatic mapping procedures.20 cases underwent lymphatic mapping using a combination of a patent blue dye and99mTc-DX, and 43 SLNs were identified, and 32 of 43 nodes were stained blue obviously. 95 SLNs and 457 NSLNs were found of 44 patients with successful lymphtic mapping,36 nodes were found to have metastases disease in 95 SLNs, and 73 nodes were found to have metastases disease in 457 NSLNs. The possibilities of SLNB and ALND remove pathologically positive lymph nodes were 37.9%(36/95), 19.7%(109/552),respectively(P=0.0002).20 patients'micrometastases in axillary lymph nodes (including 48 SLNs and 191 NSLNs)were detected. Of 7 histologically positive nodes, 7(100%) were found to contain tumor cells by IHC and RT-PCR. of 232 histologically negative nodes , 11(4.7%) nodes contained tumor cells by IHC ,and 45(19.4%) nodes contained tumor cells by RT-PCR(P=0.0000).Conclusions This study indicates that intraoperative lymphatic mapping can accurately identify the sentinel lymph nodes, the success rate achieved by combining the two mapping techniques (patent blue dye and 99mTc-DX ) is higher than the rate of results using either technique alone ; IHC and CK-19 mRNA RT-PCR are more sensitive method than histology for the detection of micrometastases in lymph nodes, and the RT-PCR is better than IHC; The techniques could enhance staging accuracy, with further refinements and experiences, might alter the role of ALND.