Significance of p53 Expression in Colorectal Cancer in Young Patients

ABSTRACT

BACKGROUND: In Korea, the incidence rate of colorectal cancer is increasing, even in patients under 40 years of age. In most young adult patients with colorectal cancer, the tumors are already in advanced stages at initiation of treatment, and they are more aggressive, so the prognosis is considered unfavorable. In addition, alteration of the p53 gene may be associated with poor prognosis for colorectal cancer. METHODS: We evaluated the p53 expression in a young adult group and an adult group with colorectal cancer who had been operated at the Department of Surgery, Doungdaemoon Hospital, Medical Center of Ewha Womans University, from 1991 to 1996. We retrospectively reviewed the medical records of a randomized sampling of patients, 17 in the young adult group under 40 years of age and 20 in the adult group over 41 years of age. Pathologic slides were prepared for immunohistochemical staining of the p53 protein. The staining results were divided into positive and negative. The chi-square test, Fisher's exact test, and student t-test were perforemd with SAS program. RESULTS: There was no difference in the sex ratio, the tumor stage, the preoperative CEA level, the size of the tumor, the location of the tumor and the histologic differentiation between the two groups (p>0.05). In the young adult group, p53 was expressed in 41% of the cases (7/17), and in the adult group, p53 was expressed in 10% of the cases (2/20); thus p53 was expressed more frequently in the young adult group (p<0.05). CONCLUSION: The p53 expression tended to be associated with age and with more aggressive colorectal cancer, p53 expression may be a useful factor in determining a poor prognosis for patients with colorectal cancer.