title: Morphological events found at the invading edge of colorectal carcinomas in baboons.
abstract: BACKGROUND
  Earlier studies at the growing edge of colorectal cancer (CRC) in humans and rats have shown dilated neoplastic glands, some with a thin layer of flattened tumor cells (FTCs), some lacking one or more groups of consecutive lining tumor cells (called glandular pores, GPs).
  
  
  METHODS
  The characteristics of the neoplastic glands at the invading edge of CRCs were investigated in 39 baboons. A total of 190 neoplastic glands were studied in the 38 cases of glandular-forming adenocarcinomas.
  
  
  RESULTS
  In the studied neoplastic glands FTCs or GPs were recorded in 44.7% (85 glands). FTCs were found in 9.5% (18 glands) and GPs in 35.3% (67 glands). Only 7.9% or 3 out of the 38 animals showed neoplastic glands with GPs in the bulk of the tumor.
  
  
  CONCLUSIONS
  In similarity to colorectal adenocarcinomas in humans, flattened tumor cells and glandular pores were found at the invading tumor edge of colorectal adenocarcinomas in baboons. A possible mechanism of host invasion is proposed.
authors.affiliation: Department of Pathology, Southwest National Primate Research Center, Southwest Foundation for Biomedical Research, San Antonio, TX, USA. carlos.rubio@ki.se
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Rubio
authors.forename: Edward
authors.initials: E
authors.lastname: Dick
authors.forename: Gene B
authors.initials: GB
authors.lastname: Hubbard
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D000818:Animals; D015179:Colorectal Neoplasms / Q000473:pathology*; D004195:Disease Models, Animal; D005109:Extracellular Matrix / Q000473:pathology; D006801:Humans; D008992:Monkey Diseases / Q000473:pathology*; D009361:Neoplasm Invasiveness; D010215:Papio; D051381:Rats