Open Access Research article

Detection of erbB2 copy number variations in plasma of patients with esophageal carcinoma

Immacolata Andolfo12, Giuseppe Petrosino1, Loredana Vecchione3, Pasqualino De Antonellis1, Mario Capasso1, Donatella Montanaro1, Marica Gemei1, Giancarlo Troncone1, Achille Iolascon12, Michele Orditura3, Fortunato Ciardiello3, Fernando De Vita3 and Massimo Zollo12*

Author Affiliations

1 CEINGE, Centro di Ingegneria Genetica e Biotecnologia Avanzate, Via Gaetano Salvatore 486, 80145, Naples, Italy

2 Dipartimento di Biochimica e Biotecnologie Mediche, Università degli Studi di Napoli "Federico II", Naples, Italy

3 Dipartimento Medico-Chirurgico di Internistica Clinica e Sperimentale "F. Magrassi e A. Lanzara" SUN, Seconda Università degli Studi, Naples, Italy

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BMC Cancer 2011, 11:126  doi:10.1186/1471-2407-11-126

Published: 11 April 2011



Mortality is high in patients with esophageal carcinoma as tumors are rarely detected before the disease has progressed to an advanced stage. Here, we sought to isolate cell-free DNA released into the plasma of patients with esophageal carcinoma, to analyze copy number variations of marker genes in the search for early detection of tumor progression.


Plasma of 41 patients with esophageal carcinoma was prospectively collected before tumor resection and chemotherapy. Our dataset resulted heterogeneous for clinical data, resembling the characteristics of the tumor. DNA from the plasma was extracted to analyze copy number variations of the erbB2 gene using real-time PCR assays.


The real-time PCR assays for erbB2 gene showed significant (P = 0.001) copy number variations in the plasma of patients with esophageal carcinoma, as compared to healthy controls with high sensitivity (80%) and specificity (95%). These variations in erbB2 were negatively correlated to the progression free survival of these patients (P = 0.03), and revealed a further risk category stratification of patients with low VEGF expression levels.


The copy number variation of erbB2 gene from plasma can be used as prognostic marker for early detection of patients at risk of worse clinical outcome in esophageal cancer.

esophageal carcinoma; cell-free DNA; erbB2 copy number variation; prognostic marker; CTCs