VI.2.3.2 Special Rules for Counting Lymph Nodes

Special rules for counting regional lymph nodes, gives guidance as to what to do when a core needle biopsy or aspiration is followed by a dissection.

Add 1 to the number of regional lymph nodes positive and examined when the core biopsy or aspiration is positive for metastases, and the lymph node dissection does not include the area where the core biopsy or aspiration was done, and that lymph node was a regional lymph node for the primary site.

Note: Do not add to the regional lymph nodes examined or positive when the area biopsied or aspirated is included in the dissection.

Add 1 only to the number of regional lymph nodes examined when the core biopsy or aspiration is negative for metastases and that lymph node was a regional lymph node for the primary site.

Note: You would not add 1 to regional lymph nodes positive because the biopsy or aspiration was negative for metastases.