This study carried out on Forty-three patients attending hospitals for elective surgical resection of colorectal cancer (CRC) from October 2002 to March 2004. Thirty-five resection margins that histopathologically proved free of malignancy taken from the normal tissue of the same patients used as controls of staining efficiency and evaluation for immunohistochemistry (IHC). p16INK4a immunoexpression in the CRN are less than 5% and regarded as negative while 32 of 43 CRC patients had positive reaction for p16INK4a.
