Immunicon Corp, Huntingdon Valley, Pa, has been granted FDA has clearance for the CellSearch™ circulating tumor cell (CTC) kit as an aid in the monitoring of patients with metastatic prostate cancer.

A sample of the patient’s blood is processed with the kit using the company’s CellTracks® system to capture and count CTCs. The clearance represents another expansion to claims for the kit, which is cleared for three of the four most prevalent cancers. It was originally cleared in January 2004 to predict progression-free and overall survival in patients with metastatic breast cancer, and was expanded to include monitoring. In November 2007, the kit was cleared by the FDA for monitoring metastatic colorectal cancer.

Prostate cancer claims about 27,000 lives annually, the vast majority of which are a result of recurrent metastatic disease, according to the American Cancer Society. Metastatic prostate cancer occurs when tumor cells spread to other locations in the body and grow.

Evaluation of CTC count at any time during the treatment of metastatic disease allows assessment of patient prognosis and predicts survival. Oncologists often have to wait several months before they can determine if a specific treatment is beneficial to the patient. Changes in CTC count can be assessed in 3 to 5 weeks, rather than in the 8 to 12 weeks required for imaging studies such as CT scans.

The kit was developed by Immunicon and is exclusively marketed by Veridex LLC, Warren, NJ, in the cancer field.