EXPRESSION OF FATTY-ACID SYNTHASE (FAS) AS A PREDICTOR OF RECURRENCE IN STAGE-I BREAST-CARCINOMA PATIENTS

BACKGROUND. Fatty acid synthase (FAS) is a molecule found in tumor cel ls from breast carcinomas of patients whose prognosis is very poor. Re cently, this molecule has been identified as the key enzyme in fatty a cid biosynthesis. This study was done to test the strength of FAS as a prognostic indicator for disease free survival (DFS) and overall surv ival (OS). METHODS. Clinical records, histologic features, immunohisto chemical expression of cathepsin D and c-erbB-2, and estrogen and prog esterone receptor status of 110 Stage I breast carcinoma patients were all associated with FAS by a chi-square test. The patterns of DFS and OS were estimated over a ten-year follow-up period using the Kaplan-M eier method. Univariate and multivariate analysis were evaluated using a log logistic regression model. Multivariate regression analysis was based on the Cox proportional hazard model. To detect FAS, cathepsin D and c-erbB-2 expression as well as estrogen and progesterone recepto r status, we used the unlabeled immunoperoxidase technique on formalin fixed, paraffin embedded tissue. RESULTS. FAS was significantly assoc iated with a higher risk of recurrence because it predicted both DFS ( P = 0.0001) and OS (P = 0.003) when evaluated as a continuous variable and DFS (P = 0.0001) when evaluated with other prognostic markers. Pe ritumoral lymphatic vessel invasion was the other most significant ind ependent predictor for DFS (P = 0.001) and OS (P = 0.003). CONCLUSIONS . FAS is a reliable prognostic marker to predict DFS and OS in patient s with early breast cancer. (C) 1996 American Cancer Society.