CLINICOPATHOLOGICAL AND IMMUNOHISTOCHEMICAL ANALYSES IN LUNG METASTASIS OF COLORECTAL-CARCINOMA

We compared the immunohistochemical staining patterns of carcinoembryo genic antigen (CEA), CA19-9 and proliferating cell nuclear antigen (PC NA) between specimens from 13 patients who had undergone surgery for c olorectal carcinoma with lung metastasis (lung metastasis group) and s pecimens from 13 patients who had no evidence of recurrence or metasta sis within at least 5 years after colorectal resection (no metastasis group). The PCNA labeling indices of primary and metastatic lesions we re 53.29+/-8.88% and 63.26+/-6.21% (p<0.001), respectively. The PCNA l abeling index in the no metastasis group was 26+/-12.9% (p<0.001). The re was no significant difference in the CA19-9 staining patterns betwe en the two groups. The CEA distribution patterns in the primary and lu ng metastatic lesions were different even in the same case. The origin al tumor cells showed apical or C1 localization, whereas metastatic ce lls showed C2 localization. These findings indicate that patients havi ng colorectal carcinoma with a high PCNA labeling index have a high pr obability of lung metastasis, and that the CEA distribution pattern wo uld change after original tumor resection.