Epidermal growth factor receptor in adrenocortical tumors: analysis of gene sequence, protein expression and correlation with clinical outcome.
Adrenocortical carcinoma is a rare but highly malignant neoplasm with still limited treatment options. Epidermal growth factor receptor (EGFR) has been shown to be overexpressed in many solid tumors, but its expression in adrenocortical carcinoma has been studied only in a limited number of cases. Therefore, we analyzed the expression of EGFR in 169 adrenocortical carcinoma samples and compared it with 31 adrenocortical adenomas. Additionally, in 30 cases of adrenocortical carcinoma, exons 18-21 of the EGFR gene were cloned and sequenced. EGFR expression was found in 128 of 169 adrenocortical carcinoma samples (76%), and in 60 of these samples (=36%) strong membrane staining was detected. However, there was no significant correlation with clinical outcome. In addition, all 30 sequenced cases revealed unmutated EGFR genes. In contrast, only 1 out of 31 adrenocortical adenomas weakly expressed the EGFR (3%). In summary, EGFR was overexpressed in more than three-quarters of adrenocortical carcinoma cases of this series. However, no mutations of the EGFR gene were found and EGFR expression was not of prognostic relevance. As EGFR is hardly expressed in adrenocortical adenomas, our results suggest that its expression in adrenocortical tumors indicates a malignant phenotype, which may be used in the differential diagnosis between adrenocortical adenomas and carcinomas.
Adam
Patrick
P
Institute of Pathology, University of Tübingen, Tübingen, Germany.
Hahner
Stefanie
S
Hartmann
Martina
M
Heinrich
Barbara
B
Quinkler
Marcus
M
Willenberg
Holger S
HS
Saeger
Wolfgang
W
Sbiera
Silviu
S
Schmull
Sebastian
S
Voelker
Hans-Ullrich
HU
Ströbel
Philipp
P
Allolio
Bruno
B
Fassnacht
Martin
M
D000306:Adrenal Cortex Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D018246:Adrenocortical Adenoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D066246:ErbB Receptors / Q000096:biosynthesis*; D005260:Female; D015870:Gene Expression; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011379:Prognosis; D046888:Tissue Array Analysis
D014408:Biomarkers, Tumor; D066246:ErbB Receptors