To investigate the application value of subclavian lymph node dissection via intermuscular approach in locally advanced breast cancer.

Clinical data of 56 patients with locally advanced breast cancer from April 2014 to April 2017 were retrospectively analyzed and divided into intermuscular approach group and axillary approach group according to different operation methods，with 28 cases in each group. SPSS 22.0 statistical software was used for analysis. Surgical indicators and other measurement data were expressed as（

Subclavicular lymph node dissection was successfully completed in both groups. The operation time，surgical bleeding volume and drainage tube retention time in the intermuscular approach group were lower than those in the axillary approach group，while the number of lymph nodes dissection was higher than that in the axillary approach group，with statistical significance（P<0.05）. The median follow-up time of the two groups was 6 years. The incidence of limb lymphedema in the intermuscular approach group and the axillary approach group was 7.1% and 25.0%，the incidence of pectoralis major muscle atrophy was 3.6% and 21.4%，the local recurrence rate was 3.6% and 17.9%，and the distant metastasis rate was 10.7% and 28.6%，respectively. The postoperative complications in the intermuscular approach group were lower than those in the axillary approach group，and the difference was statistically significant（P<0.05）.

For locally advanced breast cancer，subclavian lymph node dissection through the pectoralis major intermuscular approach is not only more thorough lymph node dissection，but also better preservation of pectoralis major and small muscle function，strong operability of surgery，and significantly improve the quality of life of patients.