GCDFP-15

Gross cystic disease fluid protein-15 (GCDFP-15) is a secreted glycoprotein with unclear function, mainly present in exocrine glandular tissues such as breast, sweat glands, salivary glands, and cerumen glands. In clinical practice, GCDFP-15 is mainly used to diagnose breast cancer. Especially, it can be positive in ovarian metastasis from breast cancer but negative in primary ovarian cancer, which makes it useful for assisting in identification. Similarly, it can be expressed in Paget's disease but absent in Paget like Bowen's disease. Meanwhile, some research suggested that GCDFP-15, as a biomarker of sweat glands, has a high positivity rate in pleomorphic lobular carcinoma of the breast, which is considered as a subtype of breast apocrine carcinoma. Moreover, GCDFP-15 is found in some prostate cancers and cervical cancers, and its high expression is associated with poor prognosis, speculated that the tumor development may affect the secretion of GCDFP-15 in cystic fluid. In addition, GCDFP-15 can specifically label salivary duct carcinoma but not expressed in salivary pleomorphic adenoma and salivary gland cyst.