Circulating tumor cells and bone metastases as detected by FDG-PET/CT in patients with metastatic breast cancer.
BACKGROUND
We evaluated the relationship between the detection and prognostic significance of circulating tumor cells (CTCs) and sites of metastases detected by 2-[fluorine-18]fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) in patients with metastatic breast cancer (MBC).


METHODS
From May 2004 to January 2008, 195 patients with relapsed/progressive MBC underwent whole-body FDG-PET/CT and provided blood samples for assessment of CTC count.


RESULTS
Higher CTC numbers were detected in patients with bone metastases relative to those with no bone lesions (mean 65.7 versus 3.3, P = 0.0122) and in patients with multiple bone metastases relative to those with one or two bone lesions (mean 77.7 versus 2.6, P < 0.001). CTCs predicted overall survival (OS) in 108 patients with multiple sites of metastases including bone (P = 0.0008) but not in 58 without bone metastases (P = 0.4111) and in 29 with bone involvement only (P = 0.3552). All 15 patients but one with human epidermal growth factor receptor 2 (HER-2) positive tumors who were treated with trastuzumab-based regimens had <5 CTCs at progression. In multivariate analysis, CTCs, but not bone metastases, remained a significant predictor of OS.


CONCLUSIONS
Presence of extensive bone metastases as detected by FDG-PET/CT is associated with increased CTC numbers in MBC.
De Giorgi
U
U
Department of Breast Medical Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX, USA.
Valero
V
V
Rohren
E
E
Mego
M
M
Doyle
G V
GV
Miller
M C
MC
Ueno
N T
NT
Handy
B C
BC
Reuben
J M
JM
Macapinlac
H A
HA
Hortobagyi
G N
GN
Cristofanilli
M
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D049268:Positron-Emission Tomography; D011379:Prognosis; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18