Polyclonal cervical tumors detected by flow cytometry.

In a prospective study, the tumors of 167 patients with invasive squamous cell carcinomas of the uterine cervix were investigated by flow cytometric measurements of the DNA-content. In 37 patients (22%) 2 or more stemlines could be detected, indicating clonal heterogeneity. The proportion of multiple stemlines was equal in stages IB to III but significantly higher in stage IV (p less than 0.01). In 14 of the 37 polyclonal tumors the DNA-value of the second peak was twice the value of the first peak, suggesting possible polyploidization. For those tumors with evidence of polyploidization that had values in the diploid, tetraploid or octaploid region (n = 9) the mean age was 35.6 +/- 11.7 years and for grossly aneuploid tumors (n = 5) the mean age was 73 +/- 12.6 years. The differences of mean age between the two groups differed significantly (p less than 0.001). Flow cytometry proved to be a useful, rapid, and sensitive method for detection of multiple stemlines.