The purpose of this work was to study the relationship between cell proliferation and P53 gene mutation with the occurrence

expansion and prognosis of cystadenocarcinomas. MIB1

which is a new monoclonal antibody against Ki-67

and P53 protein (antibody) were used to make an immunohistochemical study on 68 cases of mucinous ovarian tumors. These cases included 42 cyst adenocarcinomas

10 borderline tumors and 16 cystadenomas. Results: Compared with cystadenomas and borderline tumors

the MIB1 proliferation index was significantly higher in cystadenocarcinomas (P<0.01). In mucinous cystadenocarcinomas

The MIBI proliferation index was clearly associated with tumor stage

histological grade and residual disease (P<0.05). Immunohistochemical staining of P53 protein was positive in 28.6% of cystadenocarcinomas (P<0.05).P53 overexpre ssion was closely related to histological grade and MIB1 index(P<0.05)

but not to tumor stage and residual disease. The survival rate of patients with MIB1 index>14.2% and positive P53 Protein expression was significantly lower than that of those patients with MIB1 index<14.2% and negative P53 expression (P<0.05). atients with MIB1 index >14.2% had a 3.7 fold increased risk of death as compared with patients with MIB1 index <14.2%(P<0.01). Patients with positive P53 protein expression had a 4.7-fold increased risk of death as compared with patients with negative P53 expression(P<0.01) (Cox proportional hazards model was used.) Conclusions: The use of Ki-67 antigen and P53 protein detection on mucinous ovarian cystadenocarcinoma section could be used to determine the differentiation and prognosis of tumors.