A. Mucinous adenocarcinoma B. IHC results. Diffuse CK20 positivity and CK 7 negativity (not shown), reinforcing a metastatic colorectal adenocarcinoma. C. Metastatic 'signet-ring' cell adenocarcinoma from colorectum. Infiltrating 'signet-ring' cells in a desmoplastic stroma. Inset, showing discrete mucicarmine positivity, highlighting intracytoplasmic mucin in the tumor cells. D. CK20 positivity in the signet-ring cells. E. Diffuse CEA expression. CK 7 was negative (not shown).
Rekhi et al. Diagnostic Pathology 2008 3:39 doi:10.1186/1746-1596-3-39