Description
Why It’s Done:
• To diagnose and monitor cancer: The IHC – CEA test is often used in conjunction with other diagnostic tools to diagnose cancers, especially cancers of the colon, rectum, lung, breast, and pancreas. The presence of elevated CEA levels can suggest a tumor is present, but CEA levels can also be elevated in non-cancerous conditions, so this test is often used alongside other diagnostic methods.
• To determine tumor origin: The test is particularly useful when the tumor’s origin is unknown. For example, metastatic tumors (cancers that have spread from one organ to another) may express CEA, and the test helps in identifying the primary source of the tumor.
• To track cancer progression or recurrence: In patients who have been previously treated for cancer, the CEA test can be used to monitor for recurrence or disease progression. If CEA levels rise again after treatment, it may indicate that the cancer has returned or spread.
• To assess prognosis: Elevated CEA levels in certain cancers can be used to assess the prognosis and response to treatment. For instance, persistent or high levels of CEA after treatment may suggest that the cancer is resistant to therapy or more aggressive.
Preparation:
• Fasting: Fasting is generally not required for the IHC – CEA test, but always follow any specific instructions from your healthcare provider.
• Tissue sample: The test requires a tissue biopsy sample, which may be taken from a suspicious mass, tumor, or lymph node. The sample is typically collected using a fine needle biopsy or surgical biopsy procedure, depending on the location of the tumor.
• Medications: Inform your healthcare provider about any medications you are currently taking, especially if you are receiving chemotherapy, radiation, or immunotherapy, as these treatments can affect cancer cells and influence CEA levels.
• No special preparation: In general, there are no special dietary or lifestyle changes required before the test, but the healthcare provider may give specific instructions regarding the biopsy procedure.
