Prognostic-significance of chromosome 5q and 17p allelic deletion in colorectal adenocarcinomas.

Patient survival was analysed for 75 patients after surgery for primary colorectal adenocarcinoma with regards to allelic loss of chromosome 17p and chromosome 5q. Allelic loss of chromosome 17p occurred in 69% of patients and was not significantly associated with a poorer patient prognosis as assessed by log rank analysis of Kaplan-Meier survival plots (p = 0.161). Allelic loss of chromosome 5q occurred in 32% of patients and was significantly associated with a poorer patient prognosis as assessed by log rank analysis of Kaplan-Meier survival plots (p = 0.014). Analysis of the two variables by Cox regression analysis indicated that allelic loss of chromosome 5q was an independent variable for patient prognosis. Entry of Dukes' stage into the model resulted in a final model with Dukes' stage and allelic loss of chromosome 5q as independent significant variables in assessing patient survival. These results show that allelic loss of chromosome 5q, but not chromosome 17p provides additional prognostic information for assessing patient survival, over and above Dukes' stage.