Cancer antigen 15-3 and the grade of the breast carcinoma in newly diagnosed patients

BACKGROUND: Cancer antigen 15-3 (CA15-3) is a breast tumor marker of clinical utility. However, the utility of measuring CA15-3 in patients with breast cancer (BC) remains controversial. OBJECTIVES: To assess CA15-3 concentrations of newly diagnosed BC patients and to compare those with concentrations of apparently healthy females and within the different the grades of the carcinoma. METHODS: CA15-3 concentration of newly diagnosed BC patients (n=155) and apparently healthy age matched females (n=35) was assessed using enzyme immunoassay sandwich method with a final fluorescent detection using mini vidas immuno analyser. Nottingham grade of the carcinoma of each BC patient was recorded from the histopathology records. RESULTS: The median levels of CA15-3 of the BC patients and apparently healthy women in the study sample was 14.45 (IQR: 10.17) U/mL and 14.19 (IQR: 7.09) U/mL respectively. CA15-3 concentrations were not significantly different among BC and healthy women (p>0.05). Only 11% of women with BC had elevated CA15-3 concentrations above the reference range (30 U/mL). The BC patients were classified as Nottingham grade I (13.4%), II (47.8%) and III (38%). CA15-3. Concentrations (median and IQR) within each grade were 15.24 (6.62), 13.06 (11.56) and 17.52 (13.69) respectively. CA15-3 concentrations were not significantly different according to the grade (p>0.05). CONCLUSIONS: CA 15-3 concentrations of newly diagnosed breast cancer patients were not significantly different when compared with apparently healthy women and according to the Nottingham grading.