CA-125

Definition

CA-125 is a protein that is a tumor marker often associated with ovarian cancer. It is used in clinical settings to help diagnose and monitor the treatment of ovarian cancer, as well as to assess disease prognosis. Elevated levels of CA-125 can indicate the presence of cancer, but it can also be found in non-cancerous conditions, making it an important, yet sometimes ambiguous, tool in disease diagnosis and prognosis.

5 Must Know Facts For Your Next Test

1. CA-125 is primarily used to monitor patients with ovarian cancer but can also be elevated in conditions like endometriosis and pelvic inflammatory disease.
2. The normal range for CA-125 levels is generally considered to be below 35 U/mL, but this threshold can vary based on the laboratory and individual circumstances.
3. While high CA-125 levels are often associated with ovarian cancer, not all patients with ovarian cancer have elevated CA-125 levels, leading to the term 'false negatives.'
4. CA-125 testing is not used as a standalone diagnostic tool; it is typically combined with imaging studies and other clinical evaluations.
5. Monitoring CA-125 levels over time can provide insights into treatment effectiveness, helping healthcare providers decide on continuing or changing therapy.

Review Questions

• How does CA-125 function as a tumor marker in diagnosing ovarian cancer?
  • CA-125 functions as a tumor marker by measuring the levels of this protein in the blood, which can be elevated in individuals with ovarian cancer. A significantly high level of CA-125 may suggest the presence of the disease, prompting further diagnostic evaluations such as imaging studies. However, it is important to note that elevated CA-125 levels can also occur in other conditions, making it essential to interpret results within a broader clinical context.
• Discuss the limitations of using CA-125 as a diagnostic tool for ovarian cancer.
  • While CA-125 is valuable for monitoring and diagnosing ovarian cancer, it has several limitations. Notably, not all women with ovarian cancer will have elevated CA-125 levels, leading to false negatives. Additionally, conditions such as endometriosis or liver disease can also elevate CA-125 levels, causing potential confusion in diagnosis. This underscores the necessity for using CA-125 in conjunction with other diagnostic methods rather than as a standalone test.
• Evaluate the role of CA-125 in patient management beyond initial diagnosis of ovarian cancer.
  • Beyond initial diagnosis, CA-125 plays a crucial role in patient management by helping monitor disease progression and response to treatment. Regular testing of CA-125 levels can indicate whether a patient's cancer is responding to therapy or if there are signs of recurrence after treatment. This ongoing monitoring allows healthcare providers to make informed decisions about adjusting treatment plans and provides critical information on the patient's overall prognosis.

Related terms

Tumor Markers: Substances found in blood, urine, or tissues that can be indicative of cancer presence or progression.

Ovarian Cancer: A type of cancer that begins in the ovaries, often detected at a late stage due to vague symptoms and lack of effective screening methods.

Prognosis: The likely course or outcome of a disease; in oncology, it refers to the chances of recovery or survival following treatment.