CSP
Meaning of CSP: CSP is an older abbreviation for a phyllodes tumor, a fibroepithelial breast growth that is usually benign despite its historical name.
Definition of CSP
CSP is an abbreviation for cystosarcoma phyllodes, an older name for what is now generally called a phyllodes tumor, a fibroepithelial tumor that develops in the connective tissue of the breast rather than in its milk producing glands or ducts. The tumor's leaf-like growth pattern under the microscope gives the modern name its meaning.
The original name, cystosarcoma phyllodes, is now considered misleading, since the word sarcoma suggests an aggressive cancer, while most of these tumors are actually benign. A phyllodes tumor can also be borderline or, less commonly, malignant, a distinction determined by how the tumor's cells appear under the microscope rather than by its size alone.
A phyllodes tumor can grow quickly and become quite large within a relatively short time, and it is generally treated with surgical removal, since these tumors do not reliably respond to the treatments used for more common types of breast cancer.
Also known as
Used in a sentence
Biopsy of the rapidly enlarging breast mass confirmed a phyllodes tumor.
Good to know
The abbreviation CSP and the older name cystosarcoma phyllodes are increasingly replaced by phyllodes tumor in current practice, since most of these growths are benign rather than the sarcoma the old name implies.