FIGURE 2.

Tumor nodules in the pericolorectal adipose tissue lymph drainage area of a primary carcinoma. In TNM6, tumor nodules without histological evidence of residual lymph node in the nodule are classified in the pN category as a regional lymph node metastasis if the nodule has a smooth contour (A). A nodule with an irregular contour (B) is classified in the T category and also coded as V1 or V2. In TNM7 and TNM8, tumor nodules are no longer treated as a T category. A nodule considered by the pathologists as a totally replaced lymph node is regarded as a positive lymph node, and otherwise, it may change the node status to pN1c depending on some conditions defined differently in TNM7 and TNM8. No specific criteria for a nodule that should be diagnosed as a totally replaced lymph node are being provided other than a short explanatory note that it is “generally having a smooth contour”. (A and B), hematoxylin and eosin staining; Bar, 1 mm