Expression of CEACAM-1 in pulmonary adenocarcinomas and their metastases.

BACKGROUND: CEACAM-1 is involved in intercellular adhesion and is expressed in a variety of human tissues. In cases of malignant transformation, a down-regulation or loss of CEACAM-1 has been shown. In contrast, CEACAM-1 is not expressed in normal lung tissue or melanocytes. It has been demonstrated that an expression in these tissues is associated with the development of metastatic disease. The aim of the present investigation was to analyze a possible association between the expression of CEACAM-1 in pulmonary adenocarcinomas and their lymph node and hematogenous metastatic cells. PATIENTS AND METHODS: CEACAM-1 expression was immunhistochemically evaluated in primary tumors, lymph nodes and distant metastases of 96 patients with metastatic pulmonary adenocarcinoma who had undergone surgery between 1999 and 2002. RESULTS: Expression of CEACAM-1 was shown in 78 out of 96 primary tumors (81.3%). A significant positive correlation was found between CEACAM-1 expression on cells of the primary tumor, lymph node metastases (p < 0.005) and hematogenous metastases (p = 0.03). CEACAM-1 expression did not correlate with stage, gender, grading or patients' age. Compared to patients with tumors not expressing CEACAM-1, patients with a CEACAM-1-expressing tumor had a shorter median overall survival (21 vs. 28 months) and progression-free survival (11.7 vs. 16.3 months). CONCLUSION: CEACAM-1 is expressed in most primary pulmonary adenocarcinomas. This investigation demonstrates that its expression is preserved in lymph node and hematogenous metastases, indicating that its expression is of functional significance for both metastatic sites. These results support the prognostic relevance of the expression of CEACAM-1 in pulmonary adenocarcinoma.

Lectin histochemistry of metastatic adenocarcinomas of the lung.

BACKGROUND: Several clinical studies indicate that primary tumour cells with high metastatic potential often show aberrant glycosylation as detected by lectin histochemistry. However, it is unclear whether aberrant glycosylation is still present in metastatic deposits. The aim of the present investigation was thus to analyse a possible association between the presence of lectin binding sites of pulmonary adenocarcinoma cells and their lymph node and haematogenous metastatic cells. METHODS: For this purpose, the expression of HPA, PHA-L and UEA-I was assessed in primary tumours, lymph node metastases and haematogenous metastases of 96 patients with metastatic adenocarcinomas of the lung that underwent surgery between 1999 and 2002. Besides, lectin-binding data and other known prognostic factors were correlated with survival. RESULTS: We found a significant positive correlation between the binding of the lectins HPA (p=0.002), PHA-L (p<0.00001) and UEA-I (p<0.00001) to the cells of the primary tumour and to their lymph node metastases. There was a positive correlation between the binding of HPA to the cells of the primary tumour and the haematogenous metastases as well. Patients with tumours which did not show HPA binding sites had a median overall survival of 27.9 months (95%-CI 7.7-infinity months). Patients with a HPA binding tumour had a median overall survival of 20.9 months (95%-CI 18.5-28.7 months). CONCLUSION: This is the first investigation to demonstrate a positive correlation between the binding of the lectins HPA, PHA-L and UEA-I to the cells of the primary tumour and to their lymph node metastases. Expression of HPA binding sites is also preserved in the haematogenous metastases. In summary, our results support the hypothesis that altered glycosylation of the membrane-bound glycoproteins of the tumour cells is associated with, but not sufficient for promotion of lymphogenic and haematogenous metastasis.