[Measurement of CA19-9 in bronchial lavage fluid from patients with lung cancer]

Carbohydrate antigen 19-9 (CA19-9) was measured in bronchial lavage fluid in 21 patients with lung cancer and 4 patients with benign lung diseases (2 patients with DPB, 2 patients with BE). Bronchial lavage of the tumor-related bronchus was performed. In normal subjects, levels of CA19-9 in lavage fluid were less than 1000 IU/ml. On the other hand, in 6 patients with lung cancer, levels of CA19-9 were higher than 1000 IU/ml, and in 3 of these cases, CA19-9 levels were higher than 8000 IU/ml. All six three cases were histologically diagnosed as adenocarcinoma. Tumor resected at operation was then stained by antibody recognizing CA19-9. Tumor in cases with high levels of CA19-9 was stained immunohistochemically. These results indicate that measurement of CA19-9 in bronchial lavage fluid of the tumor-related bronchus is a useful auxiliary method in the diagnosis of lung cancer.