What is the CELLSEARCH® Circulating Tumor Cell (CTC) Test?

The CELLSEARCH® CTC Test is a simple, actionable blood test that helps oncologists assess the prognosis of patients with metastatic breast, prostate*, or colorectal cancer.


  • The first and only clinically validated, FDA-cleared blood test for enumerating circulating tumor cells (CTCs). CTCs are cancer cells that detach from a primary tumor and travel through the bloodstream or lymphatic system to other parts of the body.

...An actionable test that can help inform clinical decision making


As an adjunct to standard methods of monitoring, the CELLSEARCH® CTC Test provides:

  • An early assessment of patient prognosis
  • Detection of changes in prognosis at any time
  • The most accurate assessment of prognosis in cases where CTC and imaging are discordant in patients with metastatic breast cancer, and in cases where CTC and PSA are discordant in patients with metastatic prostate cancer

*Metastatic prostate cancer patients were defined as having two consecutive increases in the serum marker prostate-specific antigen above a reference level, despite standard hormonal management. These patients are commonly described as having androgen-independent, hormone-resistant, or castration-resistant prostate cancer. For more information on the intended use and limitations for the CELLSEARCH® Circulating Tumor Cell Test, please refer to the Instructions for Use which can be found at documents.cellsearchctc.com.

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