Comparison of S urvival between P atients with H ereditary N on - polyposis C olorectal C ancer (HNPCC) and S poradic C olorectal C ance

Background: Hereditary non polyposis colorectal cancer (HNPCC) appears to have a better prognosis thansporadic cancer. In the present study we evaluated the clinical outcomes of HNPCC patients in comparison withtheir sporadic colorectal cancer counterparts arising from the general population recorded in a populationbasedcancer registry in Iran. Patients and methods: The population studied consisted of 121 individuals including61 patients with sporadic colorectal cancer and 60 patients with HNPCC who were followed-up between 2003and 2008 in Taleghani hospital Tehran. The subjects with HNPCC were screened according to Amsterdamcriteria II and Bethesda Guidelines. All those with sporadic cancer had no familial history of colorectal cancer.Observed survival was estimated using the Kaplan-Meier method and compared with log rank test. Multivariateanalysis was performed using the Cox regression analysis.
Results: In the HNPCC group, 85.0% showed tumorsin the colon, vs. 68.9% in the sporadic cancer group. The 5-year survival was 82.5% in the HNPCC study groupcompared with only 56.4% in the sporadc cancer group (P=0.044). The age distribution at diagnosis of sporadicpatients was significantly higher than HNPCC patients (mean 50.1 years vs 44.3 years P=0.008). The hazardratio for sporadic cases was 2.93 (95% CI 1.06-8.11) compared with the HNPCC group (P=0.038).
Conclusion:Our findings corroborate the results of previous studies which showed overall survival of colorectal cancer inpatients with HNPCC is better than for sporadic CRC patients.