C-ERBB-2 ONCOPROTEIN IN THE SERA AND TISSUE OF PATIENTS WITH BREAST-CANCER - UTILITY IN PROGNOSIS

C-erbB-2 serum levels were studied in the sera of 50 healthy subjects. 56 patients with benign breast diseases and 412 patients with breast cancer. Using 15 U/ml as the cut-off, no healthy subjects, patients wi th benign diseases and only 2.4% of patients with no-evidence of disea se had serum levels higher than this cut-off point. Abnormal c-erbB-2 levels were found in 9.2% of the patients with locoregional breast car cinoma and in 45.4% of those with advanced disease. C-erbB-2 serum lev els in patients with locoregional breast cancer were not related to tu mor size or nodal involvement. By contrast, significantly higher c-erb B-2-serum levels were found in ER- or PgR-tumors than in those ER+ or PgR+ tumors, in both locoregional or metastatic tumors. The correlatio n between serum and tissue levels of C-erbB-2 was studied in the tumor s of 161 patients. Significantly higher c-erbB-2 serum levels were fou nd in patients with overexpression in tissue by immunohistochemistry, in both locoregional and advanced disease (p=0.0001). In patients with C-erbB-2 overexpression in tissue, c-erbB-2 serum levels were related to tumor size and nodes, with higher values in tumors greater than 5 cm or in those with more than 3 nodes involved. When the prognostic va lue of this oncoprotein was evaluated, patients with abnormally high p resurgical c-erbB-2 had a worse prognosis than those patients with nor mal values, in both node-negative and node-positive patients. Serum co ncentrations in patients with advanced disease, were related to the si te of recurrence with significantly higher values in patients with met astases (mainly in those with liver metastases) than in those with loc oregional recurrence. In summary, c-erbB-2 serum level seem to be a us eful tumor marker in the prognosis of patients with breast cancer.