Reliable prognostic markers are meeded in treast cancer management to help clinicians identify the patients with the high risk of recurence and arrive at more rational decisions for treatment. The nuclear phosphoprotein p53 is faintly esxpressed
in
all
normal cells and appears to function in suppressive regulation of cell cycle. Abnormally high levels of p53 protein are found in may different tyupes of cancer.
To evaluate prognostic significance of p53 mutation, the author analyzed the association between nuclear overexpression of 053 protein on immunohistochemical stain of archival cancer patients operated between september 1987 and August 1991 in
Korea
university Hospital : tumor size, axillary node involvement, menopausal status, estrogen receptor status, progesterone receptor status. DNA ploidy, and histological grade. Immunohistochemical stain of p53 protein was also perfomed on the cases of
fibroadenoma for negative control.
Twenty four (49%) cases showed overexpression of p53 protein in immunohistohemical stain of archival paraffin embedded tissue and following established prognostic parameters of 49 breast cancer patients operated between september 1987 and August
1991 in
Korea University Hospital : tumor size, axillary node involvement, menopausal status, estrogen receptor status, progesterone receptor status, DNA ploidy, and histological grade, Immunohistochemical stain of p53 protein was also perfomed on the
cases of
fibroadenoma for negative control.
Twenty four (49%) cases showed overexpression of p53 protein in immuno-histochemical staining usin gwto murine anitihuman p53 protein monoclonal antibodies (NCL-P53-DO7&NCL-P53-240, Novocastra Lab., U. K.). Although associations were found
between
p53
overexpression and large tumor size, negativity of estrogen receptor, and negativity of progesterone receptor, a
high statistical significance was found only between p53 overexpression and negativity of estrogen receptor (P<0.01).
In 47 cases which had been followed up for more than 36 months (median 50 months). The overall survival showed no statistically significant difference between two groups of patients with of without p53 overexpression. But the p53 overexpression
was
found to be significantly associated with the shorter relapse-free survival of patient (P<0.01). When combined with estrogen receptor satus, the overexpression of p53 protein may have a more significant role in prediction of prognosis.
At a result of this study, it is concluded that the p53 gene mutation can be considered as a useful prognostic marker for breast cancer patients, and more aggressive therapeutic approach is warranted to such group of patients with p53 gene
mutation.
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