A prospective evaluation of CA15-3 in stage I carcinoma of the breast

BACKGROUND: Carcinoma of the breast is characterized by a variable course with prognosis dependent on disease stage at presentation. Paradoxically, some patients with early malignancy demonstrate disease progression within a short time. The role of tumor markers in the management of carcinoma of the breast is controversial. While CA15-3 is the most widely used tumor marker in carcinoma of the breast, its role in the management of patients with early disease is controversial. STUDY DESIGN: Since 1986, all patients presenting to our unit with carcinoma of the breast have had serial CA15-3 levels measured. This study evaluates the role of serial CA15-3 levels in the management of a consecutive series of 168 patients with Stage I disease at presentation. RESULTS: The mean preoperative CA15-3 levels at presentation were significantly elevated in patients with Stage I disease compared with patients with benign disease. Sixteen patients had either locoregional (five patients) or metastatic recurrence (11 patients). CA15-3 levels were not elevated in patients with locoregional disease and were significantly elevated in patients with bony metastases and gave a mean lead time of 6.3 months over bone scintigraphy. CONCLUSIONS: Serial CA15-3 measurements are an efficient and cost-effective method of monitoring disease progression and have advantages over conventional investigations in patients with early carcinoma of the breast.