Clinicopathological features of small T1 colorectal cancers

Figure 1 Patient flow chart. CRC: Colorectal cancer.

Figure 2 A typical case of small T1 colorectal cancer with lymph node metastasis positivity. A: An 8-mm-sized lesion of erythematous color located in the sigmoid colon was detected by white light observation; B: Indigo carmine spray observation showed elevation in the center and a depression line at the edge, and was diagnosed as Is + IIc by morphology; C: By magnification observation with crystal violet staining, a non-structured area was identified around severe irregular pits diagnosed as V_N type pit pattern; D: Hematoxylin and eosin (H&E) staining showing well to moderately differentiated adenocarcinoma; E: Victoria blue staining. Vascular invasion was positive; F: Desmin staining. Depth of invasion was 3750 μm; G: D2-40 staining. Lymphatic invasion was positive; H: Dissected lymph nodes by H&E staining. Metastasis was positive.