Table 1

Summary of clinical trials reviewed that served to validate the predictive and prognostic capability of CTCs

Study Design

Primary Objective

Prospective orRetrospective

N

Line of therapy

Median PFS (months)

Median OS (months)


1. Multi-institution, double-blind, clinical trial of patients with MBC with measurable disease beginning a new therapy. CTCs assessed at baseline and at 1st follow-up clinical visit, approximately 3-4 weeks after starting therapy.14

PFS, OS

Prospective

177

Any

7.0 vs 2.7; p < 0.001 baseline assessment 7.0 vs 2.1; p < 0.001 1st follow-up

>18 vs 10.1; p < 0.001 baseline assessment >18 vs 8.2; p < 0.001 1st follow-up


2. Multi-institution, double-blind, clinical trial of patients with MBC with measurable disease on treatment. CTCs assessed at 2nd follow-up and subsequent follow-up clinical visits up to 9 months of follow-up. Sub-study of #1 above.15

PFS, OS

Prospective

177

Any

5.6 - 7 vs 1.3 - 6; p = n/a

18.6- >25 vs 6.3 - 10.9; p = 0.001


3. Multi-institution, double-blind, clinical trial of patients with MBC with measurable disease beginning a new therapy. CTCs assessed at baseline and 1st follow-up clinical visit, approximately 3-4 weeks after starting therapy for the 47% of patients who were being treated with 1st line palliative therapy. Sub-study of #1 above. 16

PFS, OS

Prospective

83

1st line

9.5 vs 4.9, p = 0.0014 baseline assessment 9.5 vs 2.1, p = 0.0057 1st follow-up

>18 vs 14.2, p = 0.0048 baseline assessment >18 vs 11.1, p = 0.0012 1st follow-up


4. Single institution, retrospective analysis of a cohort of newly diagnosed MBC patients (either with de novo MBC or newly diagnosed recurrent MBC) who had CTCs assessed at the time of initial diagnosis of MBC between 2001 and 2007. CTCs assessed at baseline, prior to starting salvage therapy.17

OS

Retrospective

185

1st line

28.3 vs 15, p < 0.001


5. Single institution assessment of a cohort of MBC patients prior to starting a new treatment regimen. CTCs assessment correlated with histology and phenotypic subtypes of breast cancer.18

Exploratory OS

Retrospective

517

Any


CTC cut-off used in all of these clinical trials compared those patients with less than 5 CTCs (<5 CTCs), compared to those who had 5 or greater CTCs (≥5 CTCs) per 7.5 ml of whole blood.

Swaby and Cristofanilli BMC Medicine 2011 9:43   doi:10.1186/1741-7015-9-43

Open Data