Cervical Glandular Intraepithelial Neoplasia (CGIN)

Last edited 11/2020 and last reviewed 11/2020

• pre-invasive stage of adenocarcinoma of the cervix is recognised as a spectrum of changes termed cervical glandular intraepithelial neoplasia (CGIN)
  • by analogy with squamous intraepithelial lesions this terminology includes adenocarcinoma in situ, cervical glandular atypia and cervical intraepithelial glandular neoplasia
    
    
• because of the difficulties of grading columnar neoplasia, this classification is divided into high (H-CGIN) and low (L-CGIN) grade
  
  
  • high grade CGIN includes adenocarcinoma in situ and features nuclei that may be morphologically indistinguishable from invasive adenocarcinoma
    • involved glands may be strikingly hyperchromatic at low power, drawing attention to the presence of the lesion even when the glandular profile is normal
    • glands may also be complex with branched, budded or cribriform areas
    • characteristically, there may be an abrupt change from normal to neoplastic epithelium within the same gland
      • range of cytological changes includes atypical nuclei with increased, abnormal mitoses stratified for the whole epithelial height
    • apoptotic bodies are increased and may be useful in distinguishing CGIN from reactive conditions
      
      
  • in low grade CGIN (L-CGIN) the most obvious feature may be increased hyperchromasia accompanied by minor degrees of nuclear enlargement, nuclear variation, loss of polarity and increased mitoses. The nuclei are generally limited to the basal two-thirds of the epithelium and there may be altered glandular profiles
    • L-CGIN is most often seen accompanying H-CGIN but may exist alone and be the sole explanation for abnormal cervical cytology