value of serum her2 ecd test from St. Gallen abstracts

[Lani]

0055 Analysis of HER-2/neu extracellular domain in serum from
breast cancer patients: Correlation with clinicopathologic
parameters and prognostic significance
D. Vrbanec1 , G. Hor vatic-Herceg2 , M. Sirotkovic-Skerlev3 , S. Kralik4 ,
S. Jelisavec-Cosic5 , Z. Kovac5 , A. Kulic5 . 1 Depar tment of Medical
Oncology, Division of Oncology, 2 Clinical Depar tment of Nuclear Medicine,
University Hospital Center Zagreb, 3 Depar tment of Pathophysiology,
University Hospital Center Zagreb and Zagreb University Medical School,
4
Clinical Institute of Laborator y Diagnosis, University Hospital Center
Zagreb, 5 Depar tment of Pathophysiology, University Hospital Center
Zagreb and Zagreb University Medical School, Zagreb, Croatia
Goals: The aim of this study was to investigate the presence of HER-2/neu
extracellular domain (ECD) in serum from breast cancer patients and to
correlate the results with various clinicopathologic parameters: patient’s
age, size and histological grade of the tumor, status of axillar y lymph
nodes, expression of estrogen and progesterone receptors and Cathepsin
D levels in tumor tissue. Prognostic value of HER-2/neu ECD in serum
was also analyzed.
Methods: The serum from seventy eight patients with invasive
breast cancer and twenty individuals without malignancy was tested for
HER-2/neu ECD using ELISA method.
Results: Thir ty eight (48%) of 78 patients with breast carcinoma and
4 (20%) of 20 healthy controls had increased HER-2/neu ECD concen-
trations (cutoff 15 g/L). The concentrations of HER-2/neu ECD in serum
ranged from 5.35 to 93.96 g/L in serum from breast cancer patients and
between 5.35 and 16.86 g/L in serum from healthy individuals. Circulating
HER-2/neu ECD was significantly associated with the histological grade
of tumors and the status of axillar y lymph nodes. Negative correlation
was obser ved between HER-2/neu ECD in serum and estrogen receptor
positivity while no association was found with progesterone receptor status.
No correlation was found between circulating HER-2/neu ECD and the
age of the patients, the size of the tumor and the levels of Cathepsin
D. Kaplan–Meier analysis showed that patients with elevated HER-2/neu
ECD in serum had poorer prognosis (5-year sur vival) than the patients
with lower HER-2/neu ECD concentrations.
Conclusion: These results suppor t the value of circulating HER-2/neu
ECD as a marker of more aggressive phenotype and as a prognostic factor
in patients with breast cancer.