Table 3.

Clinical studies incorporating exploratory CTC analysis in SCLC patients.

Investigational Drug	Phase	Number of Patients	Blood Sample Collection	CTC Detection Method	Optimal Cut-Off	Ref
Pazopanib	Phase II	56	Baseline, after the 1st cycle and at progression	CellSearch	5 CTCs	[48]
LY2510924 plus CE	Phase II	78	Baseline, cycle 1 (day 7), cycle 2 (day 1), and at 30-day follow-up after the last dose	CellSearch	6 CTCs/7.5 mL blood	[49]
Vismodegib or cixutumumab plus CE	Phase II	120	Baseline	CellSearch	100 CTCs/7.5 mL blood	[50]
Sonidegib plus CE	Phase I	14	Baseline, after cycles 1,2,4,6, every 3 cycles during maintenance therapy and at disease progression	CellSearch	No cut-off	[51]

Abbreviation: carboplatin-etoposide (CE).