Clinical significance of a tumor marker NCC-ST-439 in breast cancer--a comparative study with CA 15-3, CEA and TPA

We compared a new tumor marker NCC-ST-439 (ST-439) with CA 15-3, CEA and TPA for its clinical usefulness in 600 patients with breast cancer (81, primary; 49, recurrent; 470, non-recurrent), and confirmed the following results. The sensitivity of ST-439 (41.5%) was significantly higher (p less than 0.05) than that of CA 15-3 (26.2%), CEA (28.5%) and TPA (26.9%). The specificity of ST-439 (84.5%), however, was considerably lower (p less than 0.01) than these other three markers. In primary cases, the positive rate of ST 439 (34.6%) was significantly higher (p less than 0.05) than that of the other markers, and was remarkable in the early stage. As to the positive rate at the various metastatic sites, there were a few differences among these four markers. Because of no significant correlation among these markers, combination assay with ST-439, CA 15-3 and CEA showed an excellent sensitivity (57.7%). These results suggest that ST-439 is a useful tumor marker not only in monitoring the recurrence, but also in the diagnosis of primary cancer.