Anatomical site and size of sentinel lymph node metastasis predicted additional axillary tumour burden and breast cancer survival.

Our study identified features in SLN, namely the level of tumour invasion at SLN and tumour size in SLN, as useful predictors for both ALN metastasis and breast cancer outcome. The presence of ITC, particularly those with a deeper invasion in SLN portended a worse prognosis. Proper attention should be taken for their management.