Final answer:
CEA, or Carcinoembryonic Antigen, is a tumor marker that when elevated, is often associated with colorectal cancer. A rising CEA level can indicate the return of bowel cancer in individuals with a history of the disease. Monitoring CEA and other tumor markers is important in the follow-up of cancer patients, assisting in the tracking of disease progress or the response to treatment.
Step-by-step explanation:
A rise in the marker known as Carcinoembryonic Antigen (CEA) is associated with several types of cancer, but it is most notably linked to colorectal cancer. CEA is a protein that can be found in higher levels in the blood of some people who have cancer. Originally discovered in association with tumors of the gastrointestinal system, CEA levels can also rise in cases of lung and breast cancer. It's important to note that an elevated CEA level doesn't necessarily indicate bowel cancer specifically; it may be produced in other cancerous contexts as well.
In the case of a patient with a previous history of treated bowel cancer, a rising CEA level could indicate the potential return of cancer, often before it can be detected through imaging or physical examination. However, some oncologists debate the use of regular CEA blood tests due to the potential stress it may cause patients if the test indicates a relapse. Despite this concern, a consistent sequence of low CEA readings after treatment can provide reassurance to patients in remission, and a sequence of rising CEA levels should prompt further diagnostic evaluations, such as PET scans, to investigate the cause.
Tumor markers are substances that can be detected in higher than normal amounts when certain cancers are present. These markers come from either the tumor itself or from non-tumor cells in response to the presence of a tumor. Monitoring tumor markers like CEA is a valuable tool in the follow-up of treated cancer patients, allowing physicians to track the progress of the disease and response to treatment. CEA is one example among various cancer-specific and tissue-specific markers that can guide clinical decisions.