Gross cystic disease fluid protein
(mouse monoclonal) is a secretion from breast composed of several glycoproteins,
including GCDFP-15. It is considered to be a marker of apocrine differentiation.
Numerous studies have shown GCDFP-15 (BRST -2) to be a specific marker for
breast cancer in formalin-fixed paraffin-embedded tissues and in cytologic
preparation (fine needle aspirates). Other types of tissues that express
GCDFP-15 are axillary sweat glands and submandibular salivary
glands.