APPLICATION: The test should not be used as either a screening or diagnostic test for malignancy. It may be used to monitor effectiveness of therapy in patients with a malignancy that has been shown to produce the marker. Cancer antigen 125 (CA 125) and Cancer associated serum antigen (CASA) are markers for serous carcinoma, especially carcinoma of the ovary, but elevations are also seen in peritoneal disease of any cause.
INTERPRETATION: Persistence of an increased level after treatment indicates a significant amount of residual tumour. Decrease to a normal level after treatment may mean eradication of the tumour or persistence of only small amounts of tumour; subsequent elevation indicates regrowth of the tumour. Lesser elevations may be found in some non-malignant conditions.
