The Significance of Langerhans' Cell in Various Lung Carcinomas

Abstract

The presence of keratin positivity in tumor cells and infiltration of Langerhans cells (LC) in tumor nests and in areas of adjacent lymphocytic infiltration was investigated by ABC immunoperoxidase methods using anti-whole keratin antibody and anti-bovine S-100 protein antibody in primary (50 cases) and metastatic (5 cases) lung carcinomas. A large number of S-100 (+) dendritic cells (DC) were present in 13 out of 14 cases of bronchiolo-alveolar carcinomas which were well differentiated adenocarcinomas (ADC). Tumor cells of BAC which resembled epithelial cells of the airway were constantly positive to anti-KR antibody. Furthermore, positive KR reaction of tumor cells correlated well with the presence of S-100 (+) DC in tumor nests. Tumor cells of other lung carcinoma types showed no such relationship evidence, and S-100 (+) DC were present only in less than 30% of these cases. Irrespective of histological types of tumors, S-100(+) DC were present in adjacent lymphocytic infiltration. The prognosis of BAC is generally better than that of other ADC, because LC have the ability of antigen presentation. These S-100 (+) DC may play a role in tumor immunity.