The prognostic value of invariant chain (Ii) and Her-2/neu expression in curatively resected colorectal cancer.

Background: Current methods to predict outcome for patients with curatively resected colorectal cancer are not ideal. The combined use of molecular markers and clinicopathologic features may better identify patients who are at risk for recurrence. The Her-2/neu and invariant chain molecules may be important in cancer development and progression, but their usefulness as clinical predictors of outcome in colorectal cancer has not been well studied.

Methods: We used immunohistochemistry to determine the expression of Her-2/neu, invariant chain, p27, and p53 in primary tumor samples from 156 patients with curatively resected stage I-III colorectal cancer. The association between expression and clinical outcomes was assessed by univariate and multivariate analysis.

Results: Her-2/neu expression was detected in only 24% of cases, and high levels of invariant chain were detected in only 15%. Although patients whose tumors overexpressed Her-2/neu survived longer than those with non-overexpressing tumors, neither Her-2/neu nor invariant chain were independently associated with survival. Consistent with previous reports, high p27 expression was associated with improved outcome, whereas overexpression of p53 was associated with worse outcome.

Conclusions: Our study did not reveal a statistically significant association between Her-2/neu or invariant chain expression and clinical outcomes in patients with curatively resected colorectal cancer. However, the data suggest that Her-2/neu could be a favorable prognostic variable. Because of the low frequency of Her-2/neu expression, larger numbers of patients need to be studied for this question to be adequately answered.