[Monoclonal antibodies directed to human lung cancer]

Recently many monoclonal antibodies are applied in the clinical diagnosis of human cancers. Most of the antigens recognized by these monoclonal antibodies are carbohydrate in their chemical nature. Among these carbohydrate antigens, the sialyl SSEA-1 antigen is particularly useful for the diagnosis of lung cancers, as the elevated serum level of the sialyl SSEA-1 antigen is frequently observed in patients with adenocarcinoma of the lung (ca. 45-75%). Some of the other carbohydrate antigens, such as CA19-9, are also known to be useful for the diagnosis of lung cancers. These carbohydrate antigens are preferentially found in the sera of patients with adenocarcinoma of the lung, while the SCC antigen (TA-4) is closely associated with squamous cell carcinoma of the lung, and NSE (neuron-specific enolase) is frequently detected in the sera of patients with small cell carcinoma of the lung. The specific serum diagnosis of lung cancer of each histological type is now feasible because of the development of these appropriate tumor markers.