Colon carcinoma is one of the most common malignant tumours and the second cause of cancer-related deaths in developed countries.The objective of the research was to investigate the p53 expression in colorectal cancer and compare the expression levels of p53 with the macroscopic appearance and manner of growth of the tumours, followed by detection and identification of the expression levels of p53 as an important prognostic factor of the further course, outcome and data for the selection of appropriate therapy.Research was implemented as a prospective, clinical and experimental study. We used a postoperative material obtained by resection of colorectal cancer from 63 patients of both sexes.The results showed that the majority of tumours 36/63, i.e. 57.1% were manifested as infiltrative forms, 9/63, i.e. 14.3% as ulcerating form, and 18/63, i.e. 28.6% of tumours had a polypoid – exophytic form.The results have shown that three tumours of infiltrative forms were p53 negative and 17 of them were p53 positive. In tumours with ulcerating form, eight were p53 negative, and 16 of them were no p53 positive tumours. In vegetative tumour forms, four were p53 negative, and 15 of the were p53 positive.Positive p53 status was present in 52.4% of tumours. Expression of p53 was absent in 47.6% of the tumours and does not correlate with the macroscopic appearance and manner of tumour growth. Expression levels of p53 do not have a diagnostic, predictive and prognostic potential, while its importance is undeniable in the understanding of oncogenesis
