Comparison Of Three Different Imaging Methods In Sentinel Lymph Node Biopsy After Neoadjuvant Chemotherapy

Objective1.To explore the difference in sentinel lymph node biopsy after neoadjuvant chemotherapy by methylene blue,methylene blue plus indoeyanine green?ICG?and methylene blue plus radioactive nuclide.2.To evaluate the application value of three methods in sentinel lymph node biopsy of breast cancer after neoadjuvant chemotherapy,and to explore the feasibility of sentinel lymph node biopsy of breast cancer after neoadjuvant chemotherapy.3.To analyze the influencing factors of SLNB false negative rate after NAC,and discusse the measures and methods to reduce the false negative rate.MethodWe collected 142 patients who were diagnosed with invasive breast cancer confirmed by biopsy and completed 4-8 cycles of neoadjuvant chemotherapy before sentinel lymph node biopsy by methylene blue,methylene blue plus indoeyanine green?ICG?and methylene blue plus radioactive nuclide from January 2018 to May2019,and all lymph node metastases were observed by paraffin section,then the detection rate,false negative rate,sensitivite and accuracy of sentinel lymph node biopsy were evaluated.The date of the whole group were analyzed to find out the related factors affecting the false negative rate of sentinel lymph node biopsy after neoadjuvant chemotherapy.Result1.Of 142 patients who enrolled in the study,139 patients'SLNB were successful,467 sentinel lymph node?SLN?were tested,the detection rate of SLN was 97.20%?139/142?.In methylene blue group,the detection rate of SLN was 96.36%?53/55?,the false negative rate was18.18%?6/33?and accuracy was 88.68%?47/53?;In methylene blue plus indoeyanine green group,the detection rate of SLN was97.78%?44/45?,the false negative rate was17.39%?4/23?and accuracy was 90.91%?40/44?;In methylene blue plus radioactive nuclide group,the detection rate of SLN was 100.00%?42/42?,the false negative rate was88.00%?22/25?and accuracy was92.86%?39/42?;there was no significant difference among the three groups?P>0.05?.2.The average number of SLN was?2.47±1.03?in methylene blue group,?3.67±1.51?in methylene blue plus indoeyanine green group and?3.98±1.53?in methylene blue plus radioactive nuclide group,there were obviously differences among the three groups?P<0.001?.The double tracer group was obviously higher than the single tracer group.3.Multivariate binary Logistic regression analysis showed that N stages before chemotherapy,the number of sentinel lymph nodes detected and presence or absence of vascular tumor thrombus confirmed by postoperative pathology were independent influencing factors for false negative rate of SLNB after NAC.4.The false negative rate of SLNB in primary cN₀ breast cancer patients was7.14%;The false negative rate of SLNB in breast cancer patients was 37.5%,46.15%,9.68%,5.88%,respectively,when the initial axillary lymph was positive and the number of SLN was one,two,three or more than three.Conclusion:1.The three different sentinel biopsy methods after neoadjuvant chemotherapy all have a high detection rates,and the detection rates and false negative rates of the three methods were not statistically significant,but SLNB with double tracer was significantly better than single tracer.2.For breast cancer patients whose axillary lymph nodes turn negative after NAC,the initial axillary is negative,and SLNB can be clinically accepted.ALND can be avoided if the initial axilla is positive and the number of SLN detected is more than2.3.It is more recommended to use double tracer method for SLNA after NAC.Compared with nuclides,ICG has the advantages of simple operation,low cost and no radioactive pollution,so methylene blue combined with ICG is more suitable for clinical promotion.