# Carbohydrate Antigen (CA) 19-9

> This test measures the level of CA 19-9, a protein often released into the blood by tumor cells in the pancreas, gallbladder, or liver. It is primarily used to monitor patients who have been diagnosed with cancer to determine if treatment is working or if the disease has returned. While high levels can indicate tumor activity, this test cannot diagnose cancer on its own or be used for general screening. Additionally, certain non-cancerous conditions, such as bile duct blockages, can cause elevated results.

- Labcorp code: 002261
- Category: [Cancer Detection](https://app.picardo.health/labs/tests/cancer-detection.md)
- Price: shown at checkout, before payment.
- Blood draw: free at a Labcorp location, or $75.00 at home.
- Order link: https://app.picardo.health/labs/order?tests=002261&ref=assistant

## About ordering

A licensed physician reviews every order before any test is run, and results arrive in the person's Picardo account. Ordering is open to adults 18 and over in the US, except New York, New Jersey, Rhode Island, Pennsylvania, Maryland, Massachusetts, Hawaii and Maine. General health information, not medical advice.