Lymph node staging in colorectal cancer: Old controversies and recent advances

Figure 3 Value of immunohistochemistry in the evaluation of lymph nodes from patients with colorectal cancer. A: Micrometastasis in the subcapsular sinus of a mesocolic sentinel node evaluated by standard hematoxylin and eosin (HE) staining (original magnification, × 400); B: Micrometastasis in the subcapsular sinus of a mesocolic sentinel node evaluated by immunohistochemistry using an antibody preparation directed against pankeratin (serial section to A, original magnification, × 400); C: Atrophic perirectal lymph node with marked fibrosis after neoadjuvant treatment (original magnification, × 100); D: Identification of residual cancer cells by pankeratin immunostaining (original magnification, × 400).