Ep-CAM expression in squamous cell carcinoma of the esophagus: a potential therapeutic target and prognostic marker.
BACKGROUND
To evaluate the expression and test the clinical significance of the epithelial cellular adhesion molecule (Ep-CAM) in esophageal squamous cell carcinoma (SCC) to check the suitability of esophageal SCC patients for Ep-CAM directed targeted therapies.


METHODS
The Ep-CAM expression was immunohistochemically investigated in 70 primary esophageal SCCs using the monoclonal antibody Ber-EP4. For the interpretation of the staining results, we used a standardized scoring system ranging from 0 to 3+. The survival analysis was calculated from 53 patients without distant metastasis, with R0 resection and at least 2 months of clinical follow-up.


RESULTS
Ep-CAM neo-expression was observed in 79% of the tumors with three expression levels, 1+ (26%), 2+ (11%) and 3+ (41%). Heterogeneous expression was observed at all expression levels. Interestingly, tumors with 3+ Ep-CAM expression conferred a significantly decreased median relapse-free survival period (log rank, p = 0.0001) and median overall survival (log rank, p = 0.0003). Multivariate survival analysis disclosed Ep-CAM 3+ expression as independent prognostic factor.


CONCLUSIONS
Our results suggest Ep-CAM as an attractive molecule for targeted therapy in esophageal SCC. Considering the discontenting results of the current adjuvant concepts for esophageal SCC patients, Ep-CAM might provide a promising target for an adjuvant immunotherapeutic intervention.
Stoecklein
Nikolas H
NH
Klinik für Allgemein- und Viszeralchirurgie, Universitätsklinikum Düsseldorf, D-40225 Düsseldorf, Germany. Nikolas.Stoecklein@uni-duesseldorf.de
Siegmund
Annika
A
Scheunemann
Peter
P
Luebke
Andreas M
AM
Erbersdobler
Andreas
A
Verde
Pablo E
PE
Eisenberger
Claus F
CF
Peiper
Matthias
M
Rehders
Alexander
A
Esch
Jan Schulte Am
JS
Knoefel
Wolfram Trudo
WT
Hosch
Stefan B
SB
D000951:Antigens, Neoplasm / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D018572:Disease-Free Survival; D000071858:Epithelial Cell Adhesion Molecule; D004938:Esophageal Neoplasms / Q000378:metabolism*; D004947:Esophagus / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D015233:Models, Statistical; D015999:Multivariate Analysis; D011379:Prognosis
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D015815:Cell Adhesion Molecules; D000071858:Epithelial Cell Adhesion Molecule