Flow cytometric DNA analysis is useful in detecting multiple genetic alterations in squamous cell carcinoma of the esophagus

Abstract

BACKGROUND Although flow cytometric DNA analysis has been recognized to be a useful prognostic indicator for patients with squamous cell carcinoma of the esophagus, the biologic significance of DNA aneuploidy remains to be elucidated. METHODS Twenty-five patients with squamous cell carcinoma of the esophagus who underwent a curative subtotal esophagectomy were divided into 2 groups according to the DNA ploidy pattern. Multiple genetic changes, including the gene amplification of bcl-1, epidermal growth factor receptor, and c-myc, and the loss of heterozygosity of multiple tumor suppressor genes, including retinoblastoma, mutated in colorectal carcinoma, adenomatous polyposis coli, and deleted in colorectal carcinoma, in each case were investigated and the frequency of genetic alterations compared between both groups. In addition, the clinical outcome of these patients was also investigated. RESULTS Eleven of 15 cases in the aneuploid group demonstrated at least 1 genetic change (73.3%) whereas only 2 of 10 cases in the diploid group did so (20.0%) (P < 0.05). Both cases in the diploid group with genetic alterations had only 1 genetic change of 7 tested genes whereas 9 of 11 cases in the aneuploid group had multiple genetic alterations. Patients in the aneuploid group also showed a more unfavorable prognosis than patients in the diploid group. CONCLUSIONS Based on the findings of the current study, flow cytometric DNA analysis is considered to be useful for both detecting multiple genetic alterations and predicting the prognosis of patients with carcinoma of the esophagus. Cancer 1999;85:2322–8. © 1999 American Cancer Society.