Background: We analyzed clinicopathological variables, cell proliferation activity and genetic aberrations related to colorectal cancer in order to recognize clinically usable predictive markers of cancer recurrence.
Materials and methods: A total of 111 patients radically operated upon because of primary colorectal cancer in 1986-1991 were studied. Loss of heterozygosity (LOH) at 18q21 and replication errors were studied by polymerase chain reaction and fragment analysis. Expression of p53 protein and that of Ki-67 were studied using immunohistochemical methods.
Results: LOH at 18q21 was the only factor associated with recurrence (P = 0.03), and indicated a worse five-year cumulative survival rate (42%) than did LOH-negativity (72%) in cases of Dukes classes B and C. Expression of p53 protein indicated recurrence (P = 0.07), short disease-free time and poor survival (P = 0.03) in Dukes class A cases.
Conclusions: LOH at 18q21 appears useful in predicting recurrence and poor survival in cases of Dukes classes B and C, as does p53 expression in class A cases.