[Ca 19-9 and Ca 50 in the diagnosis of bronchial carcinoma: comparison with CEA].

The search for early tumour markers has brought to light CA 19-9 and CA 50, glycoproteins recognised by monoclonal antibodies. Since these markers are mainly used on the digestive tract it was thought useful to investigate their value in the diagnosis of lung cancer which is only rarely identified by markers in its early stages. The two markers were compared with the better known CEA on 43 healthy volunteers, 42 patients with chronic lung conditions, 26 people with localised non-neoplastic lung shadows and 255 patients with staged and histologically identified lung tumours. The results obtained reveal the two markers to be of little use in lung cancer since though satisfactorily specific they are not at all sensitive even in the advanced stages of the disease. They could however be used to advise against surgery if positive.