Profiles of ovarian cancer patients that benefit from taxane-platinum and platinum-based chemotherapy

Abstract

16005 Background: Taxane-platinum therapy (TP; regarded as more efficient than platinum-based therapy, PC) is a standard postoperative treatment of ovarian cancer patients; however, in 20 to 30% of patients the treatment is uneffective. Normal TP53 protein is a prerequisite of cancer cell response to PC, while TP53 inefficiency may enhance tumor sensitivity to taxanes. We compared the effectiveness of PC (n=253) and TP (n=199) with respect to tumor TP53 accumulation in ovarian cancer patients with FIGO stage IIB-IV disease. Methods: Immunohistochemical analysis with PAb1801 antibody was performed on 452 archival tumors; multivariate analysis by the Cox and logistic regression models was performed in all patients and in subgroups with [TP53(+)] and without TP53 accumulation [TP53(-)]. The therapeutic regimens were evaluated in comparison with each other and also with interactions with clinicopathological parameters. Results: TP enhanced probability of complete remission (CR, p=.05), platinum sensitivity (PS, p=.02) and longer survival (OS, p=.008) in the TP53(+) group. In the TP53(-) group TP did not show an advantage over PC in regard to CR and PS and it diminished a chance of platinum highly sensitive response (p=.04). However, in the TP53(-) group TP appeared to diminish risk of death of patients >53 yrs (p=.063). Analysis of interactions revealed that TP therapy might be more efficient in patients with: endometrioid and clear cell carcinomas, stage III disease, G2 tumors or residual tumor > 2cm. Nevertheless, in the TP53(-) group TP did not diminish risk of death of patients =53 yrs with these characteristics. Conclusions: Our results suggest that taxane-platinum therapy should be given to patients older than 53 years and to all with TP53 accumulation in their tumors. In the group of patients =53 yrs and with TP53(-) tumors (20% of patients in our study) treatment with PC may be equally or possibly more efficient than TP. No significant financial relationships to disclose.