Fig.4
From: A rare case of rectal cancer with perianal metastasis: a case report
a Sections of the rectal tumor were immunopositive for cytokeratin 20 (× 100) and b immunonegative for cytokeratin 7 (× 100). Sections of anal fistula tumor were c immunopositive for cytokeratin 20 (× 12.5) and d immunonegative for cytokeratin 7 (× 12.5)