Table 2. Regional Lymph Nodes (N)a,b
| NX | Regional lymph nodes cannot be assessed. |
| N0 | No regional lymph node metastasis. |
| N1 | Metastases in 1–3 regional lymph nodes. |
| N1a | Metastasis in 1 regional lymph node. |
| N1b | Metastases in 2–3 regional lymph nodes. |
| N1c | Tumor deposit(s) in the subserosa, mesentery, or nonperitonealized pericolic or perirectal tissues without regional nodal metastases. |
| N2 | Metastases in ≥4 regional lymph nodes. |
| N2a | Metastases in 4–6 regional lymph nodes. |
| N2b | Metastases in ≥7 regional lymph nodes. |
| aReprinted with permission from AJCC: Colon and rectum. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 143-164. |
| bA satellite peritumoral nodule in the pericolorectal adipose tissue of a primary carcinoma without histologic evidence of residual lymph node in the nodule may represent discontinuous spread, venous invasion with extravascular spread (V1/2), or a totally replaced lymph node (N1/2). Replaced nodes should be counted separately as positive nodes in the N category, whereas discontinuous spread or venous invasion should be classified and counted in the site-specific factor category Tumor Deposits. |
