Breast Cyst Fluid

The vast majority of breast cysts are benign and occur in patients with fibrocystic disease. Occasionally however, carcinomas may have a cystic component.

Fluid from benign cysts may be clear or cloudy, and are variable in color. Fluid from cystic carcinomas usually contain altered blood.

Not all breast cyst fluid specimens require cytologic examination, and many physicians discard these specimens if they feel certain that the cyst is benign (e.g., a young patient whose breast cyst contains clear fluid). However, it is prudent to send the specimen for cytologic examination if there is any concern about malignancy.


  1. The best way to preserve the cellular material is to transfer the fluid from the syringe to a ThinPrep vial supplied by Calpath.  The alcohol-based fixative in the ThinPrep vial will ensure optimal preservation of the cells.  Keep at room temperature until the specimen is picked up by the Calpath courier.
  2. If you do not have a ThinPrep vial, transfer the specimen to a clean, dry vial or cap the syringe and send the specimen in the syringe.  Since the specimen is fresh and lacks fixative, refrigerate if there is a delay in delivery to the laboratory.
  3. Do not prepare smears in your office because the specimen has to be concentrated by centrifugation in the laboratory before a slide is prepared.
  4. Do not add formalin to the specimen.
  5. Complete the Calpath requisition form per the instructions.

After completing the specimen collection, please do the following:

  • Place the specimen in the Calpath specimen bag.
  • Place the requisition form in the side slot of the Calpath specimen bag.
  • Call Calpath for a pickup or place the Calpath specimen bag in the location where our courier usually picks up your daily specimens.