Unbiased quantitative assessment of Her-2 expression of circulating tumor cells in patients with metastatic and non-metastatic breast cancer

作者：Ligthart S T; Bidard F C; Decraene C; Bachelot T; Delaloge S; Brain E; Campone M; Viens P; Pierga J Y; Terstappen L W M M^*

来源：Annals of Oncology, 2013, 24(5): 1231-1238.

DOI：10.1093/annonc/mds625

• automated analysis
• breast cancer
• circulating tumor cells
• Her-2
• quantitative assessment

Background: Circulating tumor cells (CTCs) can provide the basis for a liquid biopsy and may guide the use of targeted therapies. We report on unbiased quantification of Her-2 protein expression of CTCs. %26lt;br%26gt;Patients and methods: Her-2 assessment of CTCs was carried out using the CellSearch (R) system in 103 metastatic (M1) and 88 non-metastatic (M0) breast-cancer patients. Expression of Her-2 on CTCs was determined by a manual review and an automated algorithm using Her-2-fluorescein isothiocyanate (FITC) fluorescence of leukocytes to determine the Her-2-expression threshold in each sample. %26lt;br%26gt;Results: Her-2 expression of CTCs varied greatly within and among patients compared with Her-2 expression of leukocytes. In M1 patients, a threshold of 75% of Her-2 positive CTCs in patients with %26gt;= 5 CTCs was set. Applying this threshold, 9% of M1 patients with Her-2-negative primary tumors had Her-2-positive CTC status and 29% of M1 patients with Her-2-positive primary tumors had Her-2-negative CTC status. No Her-2 discrepancy was observed between CTCs and primary tumors in M0 patients. %26lt;br%26gt;Conclusions: Our findings demonstrate that Her-2 expression is heterogeneous among CTCs within each patient. We show the feasibility of unbiased quantitative and reproducible assessment of treatment targets on CTCs, opening a path towards personalized treatment.

• 出版日期2013-5