PROGNOSTIC-SIGNIFICANCE OF P53 OVEREXPRESSION IN ENDOMETRIAL CANCER

Abnormalities of p53, a tumor suppressor gene, have been considered to play an important role in tumorigenesis. Clinically, overexpression o f p53 has been reported to correlate with pear prognosis in several ty pes of tumors. In this study, we examined 221 cases of endometrioid en dometrial carcinoma for overexpression of p53 using immunohistochemist ry in patients with a median follow-up of 41 months. Immunohistochemic al analysis was performed with monoclonal antibody pAb1801. Overexpres sion of p53 was detected in 47 of 221 cases (21.3%). There was a stati stically significant correlation between p53 overexpression and poor p rognosis (P <.0001). In the early stages of cancer (stages 1 and 2), p 53 was overexpressed in 11 of 22 patients (50%) who died or had a recu rrence during follow-up. In contrast, overexpression was detected in o nly 14.7% of the 156 disease free patients during the same period (P < .0001). In advanced stages (stages 3 and 4), tumors from patients with recurrent disease had a higher frequency of overexpression (41.2%; 7 of 17) than those of disease-free patients (23.1%; 6 of 26). However, the difference between these frequencies was not statistically signifi cant. In multivariate analysis using the Cox proportional hazard model , p53 overexpression was an independent risk factor when compared with clinical stage, nuclear grade, and patient age. Our results indicate that p53 immunohistochemical evaluation of the most common form of end ometrial cancer may be useful in identifying cases of aggressive carci noma, especially in the early stages.