Expression and the prognostic relevance of p53, Bcl-2, Bax, and Ki-67 in uterine leiomyosarcoma.

Abstract

e15506 Background: Uterine leiomyosarcomas (LMS) are rare, aggressive gynecological malignancies of the female reproductive tract. They represent less than 2-5% of all uterine malignancies. Despite the advanced modern treatment modalities, according to our data 5 year overall and disease - free survival of patients with LMS is 48,5± 4,2% and 44.3 ± 4.3 %, respectively. One of the challenging directions in advancing the prognosis and optimization of treatment tactics in LMS is investigating the expression of molecular-biological markers in tumor tissue. So, the aim of our study was to evaluate the expression of p53, Bcl-2, Bax, and Ki-67 and their prognostic relevance. Methods: A retrospective chart review was done to 198 patients with LMS treated at the N.N. Blokhin Russian Cancer Research Center from 1971 to 2009. Immunohistochemical (IHC) staining for 20 patients was performed for p53, Bcl-2, Bax and Ki-67. Negative and positive IHC staining was scored for each marker. Survival was determined from the time of initial diagnosis to last follow-up. Results: Ten (50%) patients with LMS expressed p53. P53+ patients mostly had multiple metastases, compared to p53– patients with solitar metastases (60% against 20%) (g<0,05). Eleven (55%) patients expressed Bcl-2 and 4 (20%) expressed Bax. In Bcl-2 + patients distant metastases were observed in 45,5%, compared to Bcl-2 – patients were we observed metastatic disease in 77,8% (p=0,068). Expression of ki-67 was observed in 15 patients (75%). Conclusions: LMS patients with p53 expression had a poorer survival compared to LMS patients with negative expression (g53+ — 26,7±18,4% and g53– — 80,0±12,6%) (g<0,05). On opposite, the disease-free survivla is better in bcl-2+ patients, compared to patients, who don’t express bcl-2 (47,2±19,6% and 28,1±18,0%, respectevly (g>0,05). We didn’t observe statistical significant difference in survival depending on Bax expression. LMS patients with Ki-67 expression had a poorer survival compared to LMS patients with negative expression (34,9±13,1% and 60,0±20,7% , respectively) (g>0,05). Our study indicates that p53 expression may serve as a prognostic marker for LMS patients.