CD138 is a protein present on plasma cells in the bone marrow, and on certain epithelial cells. The protein is useful to diagnose any neoplasms (tumors) growing in plasma cells. If a patient is to be tested for cancer, CD138 stains can be used to spot tumor cells. The test, called Immunohistochemistry, involves obtaining a tissue specimen from the patient, and staining it with the CD138 stain. Depending on a positive or negative stain, the tumors can be classified as myelomas, lymphomas or carcinomas.
All instructions will be provided by the medical specialist. The tissue sample is likely to be collected through a surgery. The patient will be required to prepare mentally before the collection.
The specimens are observed under the microscope. If CD138 positive: Indicates Myeloma (plasma cell cancer) Or indicates Lymphoma (Lymphatic System Cancer) If CD138 negative: Usually indicates carcinomas (epithelial CE cancer) Directs towards other stains
After obtaining the specimen, the entire test procedure is done in the lab: A segment of the specimen is mounted in formaldehyde After fixation, the CD138 stain is added A separate segment is used as control. A counter stain is added to enhance visibility of the primary (CD138) stain.