681 Prognostic value of CA 15-3 in advanced breast cancer (BC) patients: Relationship with the disease extent (DE)

The prognostic value of CA 15-3 in BC patients at first relapse of disease may be ascribed to the correlation of marker levels with DE or with the tumor differentiation and aggressiveness ( Eur J Cancer, 1994 ). From Oct. 1988 to Sept. 1994 we recorded data from 293 BC patients. CA 15-3 serum levels and DE were separately evaluated before treatment onset. The DE of visceral metastases (mts) was assessed considering the percentage of organ involvement (no mts,   50%). Bone tumor load was defined as the number of skeletal segments positive at scintigraphy. Pleural effusion and lymphangitis were separately considered. Serum CA 15-3 was higher in patients with visceral involvement and with pleural effusion than in those with bone or soft tissue mts. CA 15-3 significantly correlated with liver, pulmonary and bone DE but not with soft tissue DE. Only liver and bone DE demonstrated to be independent variables at multiple regression analysis. Elevated CA 15-3 levels predicted poor survival either in overall patients or in those with visceral involvement. Performance status, menopause, DE in liver and in bone were found to be independence prognostic factors when Cox regression analysis was performed, while CA 15-3 failed to enter the model. To conclude, all these data suggest that the prognostic role of CA 15-3 is linked to the extent of disease.