title: Expression of CDX-2 and Ki-67 in different grades of colorectal adenocarcinomas.
abstract: BACKGROUND
  CDX2 is a caudal homeobox gene essential for intestinal differentiation and is specifically expressed in colorectal adenocarcinomas. Its role in colorectal carcinogenesis is not fully elucidated.
  
  
  OBJECTIVE
  To study the expression pattern of CDX2 and Ki-67 in different grades of colorectal adenocarcinomas and to observe the relationship of their staining patterns in various tumor stages and to look for correlation if any, between Ki-67 labeling index (Ki-67 LI) and CDX2 expression.
  
  
  METHODS
  A total of 74 cases were enrolled. Detailed clinical profile, peroperative findings, histological grading and staging were noted. Immunohistochemistry for CDX2 and Ki-67 was done, and Ki-67 LI was calculated. CDX2 staining was graded semi-quantitatively, and statistical analysis was done.
  
  
  RESULTS
  Age of presentation ranged from 20 to 75 years, and the male:female ratio was 1.83:1. There were 8, 47 and 13 cases of well, moderate and poorly differentiated adenocarcinomas, respectively. The mean Ki-67 LI of well, moderate and poorly differentiated adenocarcinomas were 14.25, 31.34 and 43.08 respectively, and their difference was statistically significant, correlation was also noted with stage. CDX2 expression appeared to be stronger in poorly differentiated cases, but there was no significant difference in its expression in the different grades and stages. There was no correlation between Ki-67 LI and CDX2 immunostaining pattern. The lymph node metastasis showed CDX2 positivity in all the cases.
  
  
  CONCLUSIONS
  Expression of CDX2 does not significantly change with the grade of colorectal adenocarcinomas. However, it is an important diagnostic marker in metastatic colonic lesions. The Ki-67 LI, on the other hand, showed a strong correlation with histopathological grades.
authors.forename: Anway
authors.initials: A
authors.lastname: Sen
authors.forename: Sumit
authors.initials: S
authors.lastname: Mitra
authors.affiliation: Department of Pathology, Institute of Post-Graduate Medical Education and Research (IPGMER), Kolkata, West Bengal, India.
authors.forename: Ram Narayan
authors.initials: RN
authors.lastname: Das
authors.forename: Shatavisha
authors.initials: S
authors.lastname: Dasgupta
authors.forename: Koushik
authors.initials: K
authors.lastname: Saha
authors.forename: Uttara
authors.initials: U
authors.lastname: Chatterjee
authors.forename: Krishnendu
authors.initials: K
authors.lastname: Mukherjee
authors.forename: Chhanda
authors.initials: C
authors.lastname: Datta
authors.forename: Bitan K
authors.initials: BK
authors.lastname: Chattopadhyay
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D000071616:CDX2 Transcription Factor; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D015870:Gene Expression; D006651:Histocytochemistry; D018398:Homeodomain Proteins / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D018398:Homeodomain Proteins; D019394:Ki-67 Antigen