Epidermal growth factor receptor (EGFR) in salivary gland carcinomas: potentials as therapeutic target.
OBJECTIVE
Epidermal growth factor (EGFR) is involved in angiogenesis, cell differentiation, proliferation and progression of many cancers and is an important therapy target in lung and colorectal cancer. To determine the potential applicability of EGFR targeted therapies, EGFR status of over 800 salivary gland tumors of different entities were analyzed on DNA and protein level by FISH and IHC.


METHODS
A tissue microarray was constructed from 721 carcinomas and 205 adenomas of the salivary gland. EGFR expression and EGFR gene copy number was assessed by means of immunohistochemistry and fluorescence in situ hybridization (FISH). EGFR mutation analysis of exon 19 and 21 was performed in a subset of 107 carcinomas.


RESULTS
Positive immunohistochemical staining (definition?) for EGFR was shown in 324 of 663 (48.9%) salivary gland carcinomas. The frequency was dependent on the tumor entity and ranged from 17.9% (30 of 168 cases) positive immunostaining in acinic cell adenocarcinomas to 85.7% (42 of 49 cases) in Warthin tumors. No EGFR amplification was found by FISH. EGFR mutation analysis of Exon 19 and 21 in 107 salivary gland carcinomas revealed mutations in two acinic cell adenocarcinomas.


CONCLUSIONS
EGFR protein expression is common in salivary gland tumors but is not associated with gene amplification. Activating mutations of EGFR are rare. Nonetheless, selected cases of patients with salivary gland carcinomas might potentially benefit of anti-EGFR therapy.
Institute of Pathology, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany. Electronic address: t.clauditz@uke.de.
Till Sebastian
TS
Clauditz
Institute of Pathology, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Artur
A
Gontarewicz
Institute of Pathology, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Patrick
P
Lebok
Institute of Pathology, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Maria-Christina
MC
Tsourlakis
Institute of Pathology, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Tobias J
TJ
Grob
Department of Otolaryngology, Head and Neck Surgery, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Adrian
A
Münscher
Institute of Pathology, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Guido
G
Sauter
Department of Oncology, Haematology, Bone Marrow Transplantation and Section Pneumology, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Carsten
C
Bokemeyer
Department of Otolaryngology, Head and Neck Surgery, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Rainald
R
Knecht
Institute of Pathology, Hubertus-Wald-Cancer-Center, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Waldemar
W
Wilczak
D000236:Adenoma / Q000235:genetics / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D002277:Carcinoma / Q000235:genetics / Q000378:metabolism*; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D005091:Exons; D005260:Female; D005784:Gene Amplification; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D009154:Mutation; D012468:Salivary Gland Neoplasms / Q000235:genetics / Q000378:metabolism*
D014408:Biomarkers, Tumor; D066246:ErbB Receptors