[Preoperative evaluation of malignant potential in esophageal carcinoma by nuclear DNA contents]

Employing surgically resected specimens from patients without preoperative radiation therapy, we measured the nuclear DNA contents in order to evaluate the malignant potential of esophageal carcinoma. The association of the DNA index (DI) > or = 1.7 and the intratumoral DNA heterogeneity of biopsy specimens from patients with or without preoperative radiotherapy was also analyzed in relation to problems related to preoperative evaluation of nuclear DNA contents using biopsy specimens and the influence of irradiation on nuclear DNA contents. Esophageal carcinomas in 128 cases were studied. Nuclear DNA content was measured for biopsy specimens as well as surgically resected tumors by flow cytometry according to the method of Hedley and colleagues. HET was found in 42% of surgically resected specimens, but in only 18% of biopsy specimens. In 90% of cases, dominant DI of the resected tumor was also found in the biopsy specimens. Cases of DI > or = 1.7 showed a poorer prognosis than those with DI < 1.7 in cases with preoperative radiotherapy (p < 0.05) as well as in those without it. These results indicated that DI can be an indicator for highly malignant potential of esophageal carcinoma when measuring nuclear DNA contents using not only biopsy specimens but also specimens from irradiated cases.