Examination for N (node) stage

All lymph nodes from resection specimens should be sampled. The number of nodes involved in metastatic disease (either in direct continuity with the primary tumor or by discontinuous spread) and the total number of lymph nodes examined for each nodal station should be reported (see map of lymph node stations, Appendix 2). Extra-nodal tissue extension should also be reported for extraparenchymal nodes.

N2 and N3 station nodes are designated with specific labels of "station" by the surgeon⁽¹¹⁾. The nodes found by the pathologist in resection material will often be N1 station nodes. Before labelling a lymph node as N2, the pathologist should consult the surgeon. Until recently there was no consensus on the designation of station 10 lymph nodes^(12-15), but since June 1997, station 10 lymph nodes have been accepted as N1 nodes⁽¹⁵⁾.

It is important to recognize that the determination of post-surgical pathologic tumor stage is a collaborative process involving both the clinician (surgeon) and pathologist.