[Relationship between Langerhans cells and prognosis of patients with gastric carcinoma]

Langerhans cells (LCs) in 73 cases of gastric carcinomas (GC) were quantitatively investigated by ABC immunohistochemical method using anti-S-100 protein antibody. The mean density of LCs (cell numbers/mm2) infiltrating the carcinomas showed an intimate relationship with the prognosis (P < 0.01) and the status of lymph node (LN) metastasis (P < 0.05). The density of LCs in patients without LN metastasis was significantly higher than that with LN metastasis. In 73 cases of GC, there were 35 cases of LCs(+) and 38 of LCs(++) groups. The mean survival times were 29.81 months in the former and 52.21 months in the latter. A significant relationship (P < 0.05) between the survival and degree of the density of LCs was showed by Student's t test and life table method. There were no correlation among the density of LCs and gross appearance, depth of invasion, histologic type and patients' sex. The fact indicated that LCs may play an important role in immunological defense mechanisms of host against the tumor. Patients with dense infiltration of LCs survived longer and showed less LN metastasis than those without such an infiltration. It is considered that measurement of LCs in specimens of GC may be taken as one of criteria of prognosis.