- If the patient has a sentinel node biopsy and one of the sentinel nodes is positive, as defined by tumor clusters > 0.2 mm, an axillary dissection must be performed; a total of at least 6 axillary lymph nodes, including sentinel nodes plus the subsequent dissection, must be removed for the patient to be eligible; of all the lymph nodes removed from both the sentinel node procedure and the axillary dissection, 1-3 must be positive for the patient to be eligible as a node-positive patient; if an axillary dissection is done without a sentinel node procedure, at least 6 lymph nodes must be removed and a 1-3 nodes must be positive for the patient to be considered node-positive and eligible for this study