Significance of CA 27.29 (MUC 1 glycoprotein) levels in patients with breast cancer

e11579 Background: ASCO guidelines do not support the use of CA 15–3 and CA 27.29 for monitoring patients for recurrence after primary breast cancer therapy. However, several well-designed studies have shown that an increase in CA 15–3 or CA 27.29 after primary and/or adjuvant therapy can predict recurrence an average of 5 to 6 months before other symptoms or tests. We wanted to assess the significance of measuring the tumor marker (CA 27.29 levels) to monitor the clinical progress of breast cancer. Methods: After IRB approval, we conducted a retrospective chart review of 392 patients with breast cancer who had regular monitoring of CA 27.29 levels following the diagnosis of breast cancer. A total of 2671 values of CA 27.29 were evaluated from our institution over the past 5 years (2003–2008). Patient CA 27.29 levels were correlated with clinical progression of the disease (diagnostic imaging and history and physical examinations). Results: Out of 330 patients with Stage I, II, and III after treatment with adjuvant therapy, 316 had no evidence of disease (NED) and had normal levels(<38) of CA 27.29. Out of the14 patients with clinical evidence of disease recurrence, 3 had persistently elevated levels. Of the 62 patients with stage IV breast cancer following cheomotherapy, 29 patients had clinical progression of disease with 20 (69%) patients showing increasing levels. Out of the 33 patients with no evidence of progression of disease only 4(12%) had increasing levels. Conclusions: Our trend analysis concludes that a normal CA 27.29 level in patients with Stage I, II, and III, after adjuvant treatment, correlates well with clinically NED status and might be of reassuring benefit to the patients. However, increasing levels of CA27.29 in metastatic disease correlate well with clinical progression of the disease. A large multicenter prospective study is warranted to further assess the role of CA 27.29 for disease monitoring in locally advanced and metastatic breast cancer. No significant financial relationships to disclose.