ACCUMULATION OF P53 IN RELATION TO LONG-TERM PROGNOSIS IN COLORECTAL-CARCINOMA

Objective: To evaluate the prognostic value of p53 in colorectal cance r. Design: A retrospective study to investigate the correlation betwee n p53 in tumour tissue and the course of patients' disease. Patients: One hundred and two patients who underwent radical surgery for colorec tal cancer and were followed up for a minimum of 5 years, or until dea th, were included in this study. Methods: The p53 expression in tumour tissue was studied by immunohistochemistry using CM1 polyclonal rabbi t antibody and formalin-fixed, paraffin-embedded material. Results: p5 3 accumulation was detected in 46% (47/102) of the tumours. There was no significant difference in long-term survival between the patients w ith p53 positive and negative tumours (P=0.86). Five-year survival rat es were 55% for p53 positive tumours compared with 56% for patients wi th p53 negative tumours. However, patients with p53 overexpressing tum ours showed a higher local recurrence rate than those having carcinoma s with undetectable levels of p53, 23% versus 9% respectively; the 2-y ear actuarial rates of 26% and 9% were statistically different (P=0.01 5). Conclusion: The results suggest that in colorectal carcinoma accum ulation of p53 is not associated with a difference in long-term progno sis. However, this phenomenon might be useful in the identification of patients with a high risk of local recurrence.