Cancer antigen 15-3 (CA15-3) is a protein produced by a variety of cells, particularly breast cancer cells.
A CA15-3 test may be done to check:
A CA15-3 test is usually done in a private laboratory or hospital laboratory. No special preparation is usually needed.
An increased CA15-3 value can occur in non-cancerous and cancerous conditions.
In cancerous conditions:
The doctor will decide if more tests, procedures, follow-up care or additional treatment is needed.
Thousands of Canadian Cancer Society volunteers work in regional cancer centres, lodges and community hospitals to support people receiving treatment.