A New Technique For Internal Mammary Sentinel Lymph Node Lymphscintigraphy And Influence Factors Analysis

Objective:Internal mammary chain is the most important extra-axillary lymphatic drainage of breast.So its pathologic status influence the breast cancer stage, the choice of adjuvant therapy and the prognostic evaluation.However,the the visualization rate of the internal mammary sentinel lymph node(SLN) is so low(0-47.3%) with current inject methods.The study is set out to improve the visualization rate of the internal mammary SLN via change the inject methods and analysis the influnce factors of internal mammary SLN visualization.Methods:1.One hundred and seventy-six early-stage breast cancer patients were evaluated.These objects were randomly divided into two groups and respectively given different injection techniques,that the exprimental group patients were given the evolutinal inject techniques and the cotroll group patients were given the troditionnal inject techniques. To compare the visualization rate of internal mammary SLN and axillary SLN in the two different groups.2. eighty-eight patients of the experimental group were divided into the internal mammary SLN visulization group(37 cases) and non-visulization group(51 cases),according the internal mammary SLN visulisation results.Eight clinical and pathological parameters including age, breast parenchym type, breast parenchyma thickness,axillary lymph node status, tumor numbers,tumor size,tumor location and tumor histology were analyzed with regard to internal mammary node drainage.Results:1.The visulization rate of internal mammary SLN of experimental group and control group were 4.55%(4/88) and 42.05%(37/88) respectively,and the difference was statistically significant(χ2≈34.63, P=0.00).The visulization rate of axillary SLN ofexperimental group and control group were 94.32%(83/88) and 97.73%(86/88)respectively. There was no statistically significant difference(χ2≈0.60,P=0.44). And the average number of shown axillary SLN were 2.05(180/88) and 2.41(212/88) respectively,there was no statistically significant difference((χ2≈ 7.10, P = 0.20).2.Four significant influence factors, including age(rs≈-0.33,P≈0.00),breast parenchyma thickness(rs≈0.23,P≈0.03),breast parenchyma type(rs ≈0.24,P≈0.03) and axillary lymph node(ALN) status( rs ≈0.23,P≈0.03) were found to predict radiocolloid flow into the internal mammary nodes.While tumor numbers(χ2≈0.00,P≈1.00),tumor size(χ2≈1.09,P≈0.85) tumor histology(χ2≈0.66,P≈ 0.97) and tumor location(χ2≈0.29,P≈0.87)were not related to the internal mammary SLN visulization.Conclusion:1.The evolutinal inject method can effectively increase the visulization rate of internal mammary SLN,which from 4.55% to 42.05%, and keep a high axillary SLN visulization rate at the same time.2. Age,breast parenchyma thickness, breast parenchyma type and ALN status are the influence factors of the internal mammary SLN visulization. While tumor number, tumor size,tumor location and tumor histology are not the influence factors of the internal mammary SLN visulization.