Tumor markers represent specific substances found in the blood, urine, or body tissues that can be produced by cancer cells or by the body in response to cancer or certain non-cancerous conditions. CA 27-29 is one such tumor marker. This marker helps medical professionals monitor specific health conditions.
Understanding CA 27-29
CA 27-29 is a mucin-like glycoprotein, produced by certain epithelial cells in the body. It is typically measured through a blood test. The primary role of CA 27-29 as a tumor marker is for monitoring purposes, particularly in individuals who have already been diagnosed with certain cancers. This marker is most commonly associated with breast cancer, where it can be used to track the disease’s progression or response to treatment. CA 27-29 is not used for initial cancer screening or diagnosis in the general population.
Defining an Elevated Level
What constitutes a “normal” or “elevated” CA 27-29 level can vary slightly depending on the laboratory performing the test. Generally, a normal reference range for CA 27-29 is less than 38 U/mL or 40 U/mL. Levels exceeding this threshold are classified as elevated or high. An elevated level does not automatically confirm a cancer diagnosis. These values must be interpreted by a healthcare professional within the context of an individual’s medical history, symptoms, and other diagnostic findings.
Potential Reasons for High Levels
Elevated CA 27-29 levels can arise from various conditions. The most common cancer-related reason for an increase in CA 27-29 is the recurrence or progression of breast cancer, particularly in metastatic cases. Other cancers, such as those originating in the colon, lung, ovarian, pancreatic, or stomach, can also lead to elevated levels of this marker.
Beyond cancer, several benign (non-cancerous) conditions can also cause CA 27-29 levels to be elevated. These include benign breast conditions like fibrocystic breast disease, which involves non-cancerous changes in breast tissue. Liver diseases such as hepatitis or cirrhosis can also lead to increased levels, as the liver plays a role in processing and clearing various substances from the blood. Inflammatory conditions, endometriosis, uterine fibroids, and ovarian cysts are other examples of non-malignant issues that may result in a higher CA 27-29 reading. Kidney disease can also cause an elevation, as impaired kidney function might reduce the clearance of the marker from the body.
Interpreting Your Results
Interpreting CA 27-29 test results requires careful consideration, as this marker is primarily a monitoring tool rather than a diagnostic one for initial cancer detection. A single elevated reading does not confirm cancer, and conversely, a normal level does not rule out the presence of the disease. This marker can sometimes produce false positives, meaning elevated levels occur in the absence of cancer, often due to the benign conditions previously mentioned. Conversely, false negatives can also occur, where CA 27-29 levels remain within the normal range despite the presence of cancer, especially in early stages or if the tumor does not produce this specific marker.
Healthcare providers often rely on serial measurements, tracking CA 27-29 levels over time to observe trends rather than focusing on a single result. A consistent rise in levels over several tests may suggest disease progression or recurrence, especially in a person with a history of cancer. If an elevated CA 27-29 level is detected, a healthcare professional will recommend further diagnostic tests. These may include imaging studies like mammograms, ultrasounds, CT scans, or MRIs, and potentially biopsies to investigate the underlying cause. A comprehensive evaluation by a medical professional is necessary to understand the results and determine the appropriate next steps.