Flow-cytometry DNA index of colorectal carcinomas

The authors investigated the relationship between flow cytometric DNA index (D.I.-defined as the ratio of the DNA content of malignant cells to that of normal cells) and other prognostic factors (grade, stage of the disease, anatomical site, patients' sex and age) of 20 patients with colorectal cancer. The entire material was obtained from 20 unselected and previously untreated patients. This material consists of fresh tumoural or normal tissues taken after radical colectomy for the flow-cytometric analysis. A normal diploid DNA content was found in six tumours, the other fourteen being founded to be aneuploid. All non malignant tissue samples showed normal diploid DNA content. In the current series of cases we have found that DI was significantly associated with stage but not with grade, anatomical site or other prognostic factors. Our data indicates that cytometrically evaluated DI values have probably an independent predictive power for the clinical outcome of colorectal cancer patients.