ObjectiveTo investigate the anatomical characteristics of breast lymphatic drainage in patients with breast cancer after injecting methylene blue and indocyanine green (ICG) into the intradermis of the areola.MethodsOne hundred and eighty-six patients with stage 0–Ⅱ breast cancer were collected. The sentinel lymph node (SLN) biopsy was performed by injecting methylene blue and ICG. At the same time, the number of sentinel lymphatic channel (SLC), origin angle, direction, and consistency were also studied.ResultsA total of 308 SLCs were successfully showed in the 186 patients and 679 SLNs were detected. The 95.8% (295/308) of SLCs and 93.1% (632/679) of SLNs were showed by combination in the methylene blue and ICG. The 46.8% (87/186) of patients had 1 SLC, the 40.9% (76/186) of patients had 2 SLCs, the 12.4% (23/186) of patients had 3 SLCs. The 82.8% (255/308) of SLCs flowed from the outer upper edge of the areola, the 3.2% (10/308) of SLCs flowed from the outer lower edge of the areola, the 14.0% (43/308) of SLCs flowed from the inner upper edge of the areola. The 89.9% (277/308) of the SLCs flowed mainly through the 0°—60° interval in the outer upper quadrant, 10.1% (31/308) of the SLCs flowed through the 61°—90° interval in the outer upper quadrant.ConclusionsThe consistency of SLC and SLN stained by the two tracers is good. The number of SLC is 1–3. The SLCs flow mainly through the 0°—60° interval in the outer upper quadrant of the breast, then flow into in the axilla and don’t flow into the internal mammary lymph nodes. The deep superficial lymphatic channels under the skin and the penetrating lymphatic channels can not be showed by ICG, but the SLN can be showed by it.