Clinical Significance

This test can detect the presence of Circulating Tumor Cells (CTC) in the peripheral blood of metastatic breast cancer, colorectal or prostate cancer in patients. A count of CTC of 5 or more in breast and prostate cancers and 3 CTC or more in colon cancer in 7.5 mL of blood is predictive of shorter progression free survival and overall survival. Physician can draw samples prior to a new line of therapy for baseline prediction. Physician can also draw samples at the first follow up visit for prediction of the therapy. The Veridex CellSearch® System is the only semi-automated system designed to standardize and optimize to measure CTC in peripheral blood. This test is also the only FDA approved kit for CTC detection.

Reference Range(s)

A Circulating Tumor Cell (CTC) count of ≥5 per 7.5 mL of blood at any time during the course of the disease has been reported to be associated with a poor prognosis and is predictive of shorter Progression Free Survival (PFS) and Overall Survival (OS) in patients with metastatic breast cancer. The table lists median PFS and OS based on CTC counts.

Number of CTC	PFS (months)	OS (months)
At all time <5	7.2	22.6
Baseline <5; at final draw ≥5	5.9	10.6
Baseline ≥5; at final draw <5	6.1	19.8
At all time points ≥5	1.8	4.1

CellSearch™ results should be used in conjunction with all clinical information derived from diagnostic tests (i.e., imaging, laboratory tests), physical examination and complete medical history in accordance with appropriate patient management procedures. This prognostic study does not demonstrate that any current line of therapy is any more or less effective than any other or no therapy.

Includes

A physician review and interpretation is provided with this assay.

Test Prep: None Indicated