Purpose: This study was designed to determine the reliability of DNA analysis in predicting outcome of patients with colorectal carcinoma and compare the prognostic efficacy of DNA analysis using two parameters vs. a single parameter.
Methods: Two hundred forty-eight patients with colon and rectal carcinoma were entered in the study over a period of 84 months. Thirty-one percent of carcinomas were found in the rectum. A total of 23.6 percent of cancers were found in the sigmoid colon. Majority of the patients were 60 years or older. Male to female ratio was equal. The colon bearing carcinoma was sent in a fresh state after resection for flow cytometry and DNA analysis. In this study, analysis was made, comparing two parameters (aneuploidy and S-phase fraction over 20 percent) with single parameters (aneuploidy) for staging and as a prognostic indicator in patients with colon and rectal carcinoma.
Results: The combined presence of aneuploidy and S-phase fraction over 20 indicated a poorer prognosis in patients with colon and rectal carcinoma. The prediction of patient outcome was more accurate with DNA analysis using two parameters than using a single parameter alone (P value = 0.00003).
Conclusion: In our analysis, the odds of survival are over 3.7 times greater for aneuploidy than aneuploidy plus S-phase fraction over 20 percent.