[Analysis of cellular DNA content by flow cytometry in epidermoid carcinoma of the esophagus]

Flow cytometric DNA analysis was performed in 35 patients with squamous cell carcinoma of the esophagus. The aim of this study was a) to establish a tumoral DNA pattern, b) to determine an objective parameter correlating with tumoral response to chemotherapy (5 FU-cisplatin). DNA analysis was performed in perendoscopic ranged tumoral biopsy specimens to determine the DNA ploidy (DNA index) and S phase fraction. Tumor diameter and length were evaluated by computed tomography (CT) before and after chemotherapy in 24 patients. The relative variation of this product determined a CT index. Before chemotherapy, 82 percent (76/93) of the specimens were available for assessment; 72 percent (26/36) of the tumors were aneuploid. In these tumors, the DNA index ranged from 1.23 to 2.80. Five tumors had two distinct and simultaneous aneuploid populations. CT index values were not significantly different according to the ploidy (diploid, aneuploid), the S phase fraction (low, high), the DNA content modification after chemotherapy (absent, present). In this study, DNA analysis did not allow to select patients with higher response to chemotherapy. The inter- and intratumoral phenotypic heterogeneity may be one of the responsible factors.