Recurrence of sigmoid colon cancer–derived anal metastasis: A case report and review of literature

Figure 1 Imaging documented the anal mass (see orange arrows). A: Low-density shadows on the posterior edge of the anal canal in computed tomography; B and C: magnetic resonance imaging showed increased signal in anal tissue.

Figure 2 Pathology of anal mass. A: Histology showed moderately differentiated adenocarcinoma, as orange arrow marked; B and C: Pathological staining for CK7 (B) and CK20 (C), with orange arrows marking negative and positive staining.