CA 15.3
Carbohydrate antigen 15.3, Cancer Antigen 15.3
Why do we do this test?
To monitor response to advanced carcinoma of breast and in the long term follow up to watch for recurrences.
Elevated in about 20% with early breast cancer and 80% in advanced breast cancer (which has spread/metastatic) making CA 15.3 a poor marker in carcinoma breast diagnosis or screening.
CA 15.3 is a protein produced by normal breast tissue. In many people with cancerous breast tissue, there is an increased production of CA 15.3.
It is also elevated in certain healthy individuals and other cancers such as colon, lung, pancreas, ovary or prostate and in benign conditions like cirrhosis, hepatitis, and benign breast diseases.
Specimen Type
Serum, Plasma (EDTA), Plasma (Li Heparin)
Instructions for specimen collection & Patient preparation
Specimen transportation & Processing
Separate serum as soon as possible. Transport separated serum/plasma in ice
Specimen storage & stability
For prolonged storage keep frozen at -20C. If analysis within 5 days stable at 0C.
Specimen storage duration
Reference Intervals & Target Values
< 35 U/mL
Critical Limits
Possible Pre-analytical Errors
Gross Hemolysis
Possible Analytical Errors
Insufficient serum/plasma volume, Air bubbles, Fibrin clots.
Available Government Laboratories
Recommended turnaround time
7 days

Test Method


1. Daniel W.Chan, Stewart Sell; Tumour Markers. Burtis CA, Ashwood ER. Tietz Text Book of Clinical Chemistry,3rd edition, USA, Elsevier Saunders 1999, 722-749

Last Updated : 2020-09-23 03:06:40






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