DNA image cytometry. A prognostic tool in squamous cell carcinoma of the esophagus? In 45 patients who underwent an esophagus resection due to a squamous cell carcinoma, in addition to the TNM classification and usual morphologic criteria, the paraffin-embedded material underwent deparaffinization, was rehydrated, and was mechanically and enzymatically processed into a single-cell solution. For evaluating the DNA histogram this was analyzed with the help of automatic single-cell cytophotometric study. The method, contrary to that of flow cytometric study, allows for the selective analysis of tumor cells due to the electronically, previously given selection criteria, whereas artifacts, stroma, and infection cells remain excluded from analysis. The multivariate analysis shows that the prognosis is only correlated with DNA content of the tumor cells. Patients with diploid tumors had a median survival time of 32 months as compared with the 22 months of patients with hypotriploid tumors, and 6.5 months with hypertriploid tumors. DNA cytometric analysis should be included when diagnosing patients with esophagus carcinoma. 