title: The role of myofibroblasts at the tumor border of invasive colorectal adenocarcinomas.
abstract: BACKGROUND
  In order to elucidate the significance of myofibroblasts in invasive growth of colorectal adenocarcinomas, we examined the number of myofibroblasts at the tumor border of colorectal adenocarcinomas.
  
  
  METHODS
  A total of 91 invasive colorectal adenocarcinomas were examined immunohistochemically using anti-alpha-smooth muscle actin (ASMA) and high-molecular-weight caldesmon (h-CD) antibodies; 25 carcinomas confined to the submucosa (sm carcinomas), 40 carcinomas confined to the muscularis propria (mp carcinomas) and 26 carcinomas invading the subserosa or adventitia (ss carcinomas). We considered ASMA-positive and h-CD-negative stromal cells as myofibroblasts.
  
  
  RESULTS
  Twenty-seven (67%) of the 40 mp carcinomas and 25 (96%) of the 26 ss carcinomas had a small number of myofibroblasts at the tumor border facing the muscularis propria.
  
  
  CONCLUSIONS
  Although direct evidence is lacking, there is a possibility that the further immediately vertical and radial invasion of carcinoma cells into the subserosa or adventitia is associated with a smaller number of myofibroblasts at the tumor border facing the muscularis propria in mp carcinomas, resulting in a low incidence of mp and a high incidence of ss carcinomas in the colorectum.
authors.affiliation: First Department of Pathology, Kochi Medical School, Japan. nakayamh@kochi-ms.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Nakayama
authors.forename: H
authors.initials: H
authors.lastname: Enzan
authors.forename: E
authors.initials: E
authors.lastname: Miyazaki
authors.forename: K
authors.initials: K
authors.lastname: Naruse
authors.forename: H
authors.initials: H
authors.lastname: Kiyoku
authors.forename: M
authors.initials: M
authors.lastname: Hiroi
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D002452:Cell Count; D016009:Chi-Square Distribution; D015179:Colorectal Neoplasms / Q000473:pathology*; D005347:Fibroblasts / Q000502:physiology*; D006801:Humans; D009130:Muscle, Smooth / Q000166:cytology*; D009361:Neoplasm Invasiveness