PROGNOSTIC VALUE OF CHROMOSOME 1P ALLELIC LOSS IN COLON-CANCER

Background & Aims: Current evidence suggests that there may be a tumor -suppressor gene on chromosome 1p associated with colorectal cancer. T he aim of the present study was to determine whether allelic loss on c hromosome 1p is of prognostic value in colorectal cancer. Methods: Pol ymerase chain reaction was used to assess allelic loss of five chromos ome 1p microsatellite markers in tumor specimens. Genomic DNA was prep ared from archival tumor and corresponding normal tissue specimens fro m 116 patients who had undergone curative treatment for adenocarcinoma of the colon. Allelic loss was correlated with disease-free interval and survival. Results: Deletion of 1p sequence was detected in 22 of 8 2 tumors. Deletions of the microsatellite markers D1S228 (1p36) and HY -TM1 (1p32) were significantly associated with poor survival (P < 0.05 ): relative risk, 4.1; 95% confidence interval, 1.25-9.23 for D1S228; and relative risk, 6.6; 95% confidence interval, 1.4-19 for HY-TM1. Lo ss of heterozygosity at D1S228 was also associated with shorter diseas e-free interval: relative risk, 4.5; 95% confidence interval, 1.3-11. Conclusions: Allelic loss in the 1p36 and 1p32 regions of chromosome 1 appears to be an independent predictor of poor prognosis in patients with adenocarcinoma of the colon.