A specific and rapid receptor assay for squamous-cell carcinoma of human esophagus.

A specific radioreceptor assay, for squamous-cell carcinoma of the human esophagus, using 2G3 monoclonal antibody, has been developed for the first time. In this assay a new mathematical parameter of the Scatchard plot has been introduced for the correct measure of binding capacity (BCcm = x cos alpha). This is the perpendicular distance from the origin to the Scatchard plot line. It is always a positive quantity and is directly proportional to both the x and y intercepts for expressing the binding capacity. The assay is highly sensitive and can be used to differentiate various types of esophageal tumors such as squamous-cell carcinoma, adenocarcinoma, ulcerative growth and also a benign growth. BCcm significantly varies in the case of squamous-cell carcinoma tumors compared to adenocarcinoma and other types of tumor of the human esophagus. The assay can be completed in about 4 h and it may be used as a clinical diagnostic test.