From the Guidelines
Elevated Cancer Antigen 27.29 (CA 27.29) levels are not recommended for routine surveillance of patients with breast cancer after primary therapy, as they lack sufficient sensitivity and specificity for breast cancer screening or diagnosis, and their role in monitoring treatment response is limited to use in conjunction with other diagnostic tools 1.
Significance of Elevated CA 27.29
The significance of elevated CA 27.29 levels is primarily related to its potential use in monitoring treatment response and detecting recurrence in patients with breast cancer. However, according to the American Society of Clinical Oncology (ASCO) guideline update in 2013, the use of CA 15-3 or CA 27.29 is not recommended for routine surveillance of patients with breast cancer after primary therapy 1.
Limitations of CA 27.29
Elevated levels of CA 27.29 may indicate the presence of breast cancer or its recurrence, but can also be elevated in other conditions including benign breast disease, ovarian cancer, colon cancer, liver disease, and kidney disease. The test is not specific enough to be used alone for breast cancer screening or diagnosis.
Clinical Use of CA 27.29
For breast cancer patients, CA 27.29 may be used in conjunction with other monitoring tools such as imaging studies and physical examinations to track treatment effectiveness. Decreasing levels may indicate a positive response to therapy, while increasing levels might suggest disease progression. However, the ASCO guideline update in 2007 states that present data are insufficient to recommend routine use of CA 15.3 or CA 27.29 for monitoring patients for recurrence after primary breast cancer therapy 1.
Recommendations
The ASCO guideline update in 2013 recommends against the use of CA 15-3 or CA 27.29 for routine surveillance of patients with breast cancer after primary therapy, and instead suggests the use of history, physical examination, patient education, and mammography for follow-up care 1.
- Key points to consider when interpreting CA 27.29 results include:
- Elevated levels may indicate disease progression or recurrence
- Decreasing levels may indicate a positive response to therapy
- The test should not be used alone for breast cancer screening or diagnosis
- The test may be used in conjunction with other diagnostic tools to monitor treatment response
- Routine surveillance with CA 27.29 is not recommended after primary therapy 1
From the Research
Significance of Elevated Cancer Antigen 27.29 (CA 27.29)
- Elevated CA 27.29 levels are associated with breast cancer, particularly in patients with metastatic disease 2, 3, 4, 5, 6
- CA 27.29 is a soluble form of glycoprotein MUC1, which is overexpressed in tumors involving glandular epithelial cells, such as breast tumors 3
- The US Food and Drug Administration has approved the use of CA 27.29 for monitoring disease activity in breast cancer patients 2, 3
- Elevated CA 27.29 levels can be used to detect recurrent or metastatic disease, with lead times of approximately 2-9 months 3
- However, false-positive results can occur in patients with benign breast disease, ovarian cysts, liver disease, or pulmonary fibrosis 3, 4, 5
Clinical Utility of CA 27.29
- CA 27.29 can be used in combination with other tumor markers, such as CA 125, to improve the detection of breast cancer recurrence 4
- The use of CA 27.29 in primary breast cancer patients before the start of systemic treatment may have prognostic relevance and can predict dissemination of the disease 5
- Larger tumor size, lobular histology, older age, and postmenopausal hormone status are associated with higher CA 27.29 levels 5
- CA 27.29 elevation can appear earlier than CA 15.3 as a sign of metastases in some cases, suggesting the potential benefit of using these markers in combination 6
Limitations and Potential Confounding Factors
- CA 27.29 levels can be elevated in patients with non-malignant conditions, such as pulmonary fibrosis, which can lead to false-positive results 2, 3
- The clinical value of CA 27.29 in routine surveillance of early-stage breast cancer is limited, and its use is generally recommended in the metastatic setting 2