Prognostic significance of deletion and over-expression of the p53 gene in epithelial ovarian cancer.
OBJECTIVE
To define the deletion or over-expression of p53 genes and their prognostic significance in epithelial ovarian cancers.


METHODS
A total of 26 patients with epithelial ovarian cancer, who had undergone second-look laparotomy after primary surgery and six courses of platinum-based chemotherapy were included in the study. Paraffin-embedded archival tissue samples of all cases were examined for deletion and over-expression of p53 gene by FISH and immunohistochemical methods, respectively. The relation between these findings and clinico-pathological prognosticators or survival of the patients were analyzed by the Fisher Exact chi2 test, Cox regression model and life table analysis.


RESULTS
p53 gene deletion, related to single or double allele, was determined in all cases with a range of 6% to 75% of the cancer cells. When 40% was accepted as the cut-off ratio for the deletion rate, seven (26.9%) of the cases were observed to have p53 deletion. Although p53 over-expression was defined in 12 (46.1%) patients, four of whom were also accompanied by p53 deletion, there was no relation between the p53 deletion and over-expression (p>0.05). p53 deletion was also not related to any prognostic factors or survival of the patients (p>0.05). However, cases with p53 over-expression had significantly more advanced stage and higher-grade tumors, and shorter median survival (p>0.05-0.01).


CONCLUSIONS
p53 gene mutation determined by over-expression of p53 protein has been suggested as an important prognostic factor for epithelial ovarian cancer, however, it has not always been accompanied by p53 deletion.
Ozalp
S S
SS
Osmangazi University School of Medicine, Department of Gynecology and Obstetrics, Section of Gynecology Oncology, Eskisehir, Turkey.
Yalcin
O T
OT
Basaran
G N
GN
Artan
S
S
Kabukcuoglu
S
S
Minsin
T H
TH
D000328:Adult; D000368:Aged; D005260:Female; D017353:Gene Deletion; D016158:Genes, p53; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008875:Middle Aged; D009375:Neoplasms, Glandular and Epithelial / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D011379:Prognosis; D015996:Survival Rate