Circulating tumor cell counts/change for outcome prediction in patients with extensive-stage small-cell lung cancer

Aims: As data on the use of circulating tumor cells (CTCs) to predict patient outcomes in extensive-stage small-cell lung cancer (ES-SCLC) remain inconclusive, we investigated the clinical value of CTC determination in an open-label, multicenter study of 91 patients with newly diagnosed ES-SCLC. Materials & methods: Blood CTC counts were determined using the CellSearch (R) system at baseline, after the second cycle of chemotherapy, and on disease progression. Results & conclusion: Following the second cycle of treatment, CTC numbers and the change in CTCs were strong, significant and independent indicators for both progression-free survival and overall survival in ES-SCLC. The CTC change was associated with both refractory disease (response to initial therapy <= 3 months) and sensitive disease (response to initial therapy >3 months).