Author: Nat Pernick, M.D. (see Authors page)

Revised: 17 November 2015, last major update July 2013

Copyright: (c) 2003-2015,, Inc.

PubMed Search: 45M1
Page views in 2018: 32
Page views in 2019 to date: 1
Cite this page: 45M1. website. Accessed January 19th, 2019.
Definition / general
  • Antibody against MUC5AC, a gastric mucin, with epitope located in the C-terminal cysteine-rich part (FEBS J 2008;275:481)
Uses by pathologists
  • To detect gastric mucins
Case reports
  • 58 year old man with recurrence of gastric cancer with mucin phenotype (Surg Today 2007;37:325)
  • 78 year old man with 45M1+ ampullary signet-ring cell carcinoma and ampullary adenocarcinoma (JOP 2011;12:162)
Microscopic (histologic) images

Images hosted on other servers:

Ampulla of Vater: coexisting signet-ring cell carcinoma and adenocarcinoma (45M1+, fig 4)


Pancreas: mucous gland hyperplasia (45M1+)

Stomach (distal): < 1 mm lesions of well-differentiated adenocarcinoma (45M1+)

Positive staining - normal
  • Gastric epithelium
Positive staining - disease
Negative staining
  • Mature small intestinal goblet cells