Fig. 3.

Representative case with discrepancy between TP53 mutation and p53 IHC pattern. A&B Tumor area from which DNA was extracted for NGS analysis. Tumor cell purity is in acceptable range (Hematoxylin & Eosin, A: X4, B: X10 objective lens, respectively). C Null type pattern of p53 immunostaining is observed. No TP53 mutation was detected in this case (p53 immunohistochemistry, × 10 objective lens). D, E Adenocarcinoma of the cecum with comedo-type necrosis. Area from which DNA has been extracted is shown in E (Hematoxylin & Eosin, D: X1.25, and E: X4 objective lens, respectively). F Overexpression pattern of p53 immunostaining is noted in the absence of detectable TP53 mutation (p53 immunohistochemistry, × 4 objective lens). G, H Moderately differentiated adenocarcinoma of the rectum. DNA has been extracted from the area shown in G (Hematoxylin & Eosin, G: X4, and H: X10 objective lens, respectively). I Overexpression pattern of p53 immunostaining is noted in the absence of detectable TP53 mutation. This patient did not receive neoadjuvant chemoradiation therapy (p53 immunohistochemistry, × 10 objective lens)