Prognostic Significance of p53 Expression, Chromosome 17 Copy Number, and DNA Ploidy in Non-Metastasized Colorectal Carcinomas (Stages IB and II)

Background and Methods: Paraffin-embedded tumor tissue from 101 non-metastasized colorectal adenocarcinomas (tumor stages IB and II-that is, pT2 and 3, pNO, MO) was investigated for p53 expression by immunohistology (IH) (moab DO1), chromosome 17 (#17) copy number by interphase cytogenetics using non-radioactive in situ hybridization (NISH) with a centromer-specific DNA probe (D17Z1), and DNA ploidy by flow cytometry (FCM). The aims of the study were 1) to test whether numerical #17 aberrations are involved in functional TP53 loss in locally confined colorectal carcinomas; 2) to search for correlations between aberrant p53 expression and #17 aberrations with DNA ploidy and histopathology; and 3) to test the prognostic significance of these factors. Results: Sixty cases (59.4%) showed nuclear p53 expression in IH (low-grade p53 accumulation (