Significance of circulating tumor cells in patients with squamous cell carcinoma of the head and neck: initial results.

Objectives: to present and discuss a high-performance negative depletion method for the isolation of circulating tumor cells (CTCs) in the blood of patients with head and neck cancer and to determine the correlation between the presence of CTCs and early clinical outcome in these patients.

Design: prospective clinical follow-up study of patients with squamous cell carcinoma of the head and neck (SCCHN) undergoing surgical intervention, who had peripheral blood examined for the presence of CTCs.

Patients: the study population comprised 48 patients diagnosed as having SCCHN and undergoing surgical intervention.

Intervention: a negative depletion process to isolate and quantify CTCs from the blood of patients with SCCHN using immunomagnetic separation was developed and validated. Immunostaining for cytokeratin was performed on the enriched samples to determine the number of CTCs extracted from each patient's blood sample. Correlation of the presence of CTCs, tumor stage, nodal status, clinical characteristics, and outcome was made.

Main Outcome Measure: disease-free survival.

Results: our initial data, that have a mean follow-up of 19.0 months, suggest that patients with no detectable CTCs per milliliter of blood had a significantly higher probability of disease-free survival (P = .01). There was no correlation between the presence of CTCs with regard to age, sex, tumor site, stage, or nodal involvement.

Conclusions: our enrichment technology, based on the removal of normal cells, has been used on the peripheral blood of patients with head and neck cancer for which follow-up data were collected. If no CTCs were present, a statistically significant improved disease-free survival was observed in SCCHN. A blood test with such a prognostic capability could have important implications in the treatment of patients with head and neck cancer.