Transformation of pleomorphic adenoma to carcinoma ex pleomorphic adenoma of the parotid gland is independent of p53 mutations.
OBJECTIVE
This retrospective study was performed to evaluate the status of p53 in pleomorphic adenomas and carcinomas ex pleomorphic adenoma in the parotid gland. As loss or mutation of p53 can cause malignant transformation, the possible degeneration of pleomorphic adenomas to carcinomas ex pleomorhic adenoma was investigated by mutational analysis.


METHODS
Twenty-five Patients including 14 patients with pleomorphic adenomas and 11 patients with carcinoma ex pleomorphic adenoma of the parotid gland were examined for p53 status. DNA was extracted out of paraffin-embedded tissue and PCR was performed for the coding exons 2-11. Denaturing gradient gel electrophoresis (DGGE) was carried out for mutational analysis and DNA sequencing was performed in case of a suspected mutation.


RESULTS
Fourteen pleomorphic adenomas and 11 carcinomas ex pleomorphic adenoma were screened for p53 status and potent mutations. Subsequent sequencing of the distinct exons showed no mutation.


CONCLUSIONS
We could not detect mutations of p53 neither in benign nor malignant parotid tumors and we therefore assume that p53 plays no role in the transformation from pleomorphic adenoma to carcinoma ex pleomorphic adenoma.
Gedlicka
Claudia
C
Department of Otorhinolaryngology, Medical University of Vienna, 1090 Vienna, Austria.
Item
Chike B
CB
Wögerbauer
Markus
M
Martinek
Helga
H
Heiduschka
Gregor
G
Erovic
Boban M
BM
Ch Grasl
Matthaeus
M
Thurnher
Dietmar
D
D008949:Adenoma, Pleomorphic / Q000235:genetics*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D016158:Genes, p53 / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010307:Parotid Neoplasms / Q000235:genetics*; D012189:Retrospective Studies