Table 2.

Concordance of CTC status (CTC-positive vs. CTC-negative) between CellSearch and IE/FC at baseline and 7 to 14 days after initiation of therapy using the cutoffs, ≥0.67 CTC/mL and ≥1 CTC/mL

CellSearch
IE/FCPositiveNegative
Baseline
 ≥0.67 CTC/mLa
  Positive25328
  Negative124557
374885
 ≥1 CTC/mLb
  Positive15621
  Negative85664
236285
7–14 days
 ≥0.67 CTC/mLc
  Positive18925
  Negative84250
245175
 ≥1 CTC/mLd
  Positive13518
  Negative104757
235275
  • aKappa = 0.63 (good agreement); SE of kappa = 0.08; 95% CI, 0.47–0.80.

  • bKappa = 0.57 (moderate agreement); SE of kappa = 0.10; 95% CI, 0.37–0.77.

  • cKappa = 0.49 (moderate agreement); SE of kappa = 0.11; 95% CI, 0.27–0.70.

  • dKappa = 0.50 (moderate agreement); SE of kappa = 0.11; 95% CI, 0.28–0.72.