CA 27-29

CA 27-29

CA 27-29 is a tumor marker that is primarily used in the monitoring of breast cancer. It is a glycoprotein antigen that is associated with the MUC1 protein, which is overexpressed in many breast cancer cells.

Structure and Function

CA 27-29 is a circulating antigen that is part of the MUC1 mucin family. Mucins are high molecular weight glycoproteins that play a role in cell signaling and forming protective mucous barriers on epithelial surfaces. In the context of cancer, MUC1 is often overexpressed and aberrantly glycosylated, which can contribute to tumor progression and metastasis.

Clinical Use

CA 27-29 is used primarily as a tumor marker in the management of breast cancer. It is not used for screening or diagnosis but is valuable in monitoring disease progression or response to treatment in patients with previously diagnosed breast cancer.

Monitoring

The levels of CA 27-29 can be measured in the blood. An increase in CA 27-29 levels may indicate disease progression or recurrence, while a decrease may suggest a positive response to treatment. However, it is important to note that CA 27-29 levels can be elevated in conditions other than breast cancer, such as liver disease, ovarian cancer, and pancreatic cancer.

Limitations

While CA 27-29 can be a useful tool in monitoring breast cancer, it has limitations. Not all breast cancer patients will have elevated CA 27-29 levels, and some patients with elevated levels may not have active disease. Therefore, CA 27-29 should be used in conjunction with other diagnostic tools and clinical evaluations.

Comparison with Other Tumor Markers

CA 27-29 is often compared with CA 15-3, another tumor marker used in breast cancer management. Both markers are associated with the MUC1 protein, and they have similar clinical applications. However, some studies suggest that CA 27-29 may have slightly better specificity, while CA 15-3 may have better sensitivity.

Conclusion

CA 27-29 is a valuable marker in the management of breast cancer, particularly for monitoring treatment response and detecting recurrence. However, its use should be considered as part of a comprehensive approach to patient care, incorporating other diagnostic and monitoring tools.

References

• American Cancer Society: Tumor Markers
• National Cancer Institute: Breast Cancer Treatment

See Also

• Breast Cancer
• Tumor Marker
• CA 15-3