Is dissection of the internerve tissue during axillary lymphadenectomy for breast cancer necessary?

Aims: The study evaluates the necessity of dissecting the tissue between the long thoracic and thoracodorsal nerves (internerve tissue) during axillary dissection in breast cancer surgery. By reviewing the lymph node yield and the metastatic rate in the internerve tissue, we examine whether the internerve tissue could be left in situ to minimize the risk of nerve injury. Methods: A prospective study was conducted on 30 consecutive women undergoing axillary lymphadenectomy for breast cancer. The internerve tissue remaining was excised separately after a routine axillary dissection and was examined by the same pathologist. Results: Twenty (67%) of 30 internerve specimens contained lymph nodes; the internerve nodes were positive for carcinoma in three cases (10%). In one case the lymph node in the internerve tissue was the only metastatic node in the axilla. Conclusions: There is a significant incidence of lymph nodes (67%) and axillary node metastases (10%) in the tissue lying between the long thoracic and thoracodorsal nerves. Therefore excision of this internerve tissue is strongly recommended in order to optimize decision making regarding adjuvant treatment and oucome in women with operable breast cancer.