[New prognostic factors in patients with esophageal squamous carcinoma]

The correlation between the clinical outcome in patients with esophageal squamous cell carcinoma and amplification or overexpression of protooncogenes was analyzed retrospectively. Overexpression of c-erb B oncogene product, namely, epidermal growth factor receptor (EGFR) was observed in about a half of the esophageal cancer tissues. The cumulative survival rate of patients with overexpression of EGFR in the primary tumors was significantly lower than that of patients without overexpression. Amplification of c-erb B, and coamplification of hst-1 and int-2 oncogenes were examined by slot-blot hybridization using DNAs extracted from formalin-fixed and paraffin-embedded blocks of tissues. Amplification of c-erb B and coamplification of hst-1/int-2 were observed 14% and 28%, respectively. The cumulative survival rate of patients with int-2/hst-1 coamplification or erb-B amplification, were significantly lower than that of the patients without coamplification or amplification. These data suggest that amplification or overexpression of oncogenes is a new biological indicator of prognosis in patients with esophageal squamous cell carcinoma.