Predictors for optimal cytoreduction following neoadjuvant chemotherapy in advanced epithelial ovarian carcinoma

5512 Background: Neoadjuvant chemotherapy (NAC) is increasingly used to treat patients (pts) with presumed advanced-stage epithelial ovarian cancer (EOC) who are deemed ineligible for upfront debulking surgery (DS). DS following NAC offers a survival benefit to those pts in whom optimal cytoreduction (< 1 cm residual tumor) is achieved. However, not all women who commence NAC have a subsequent attempt at DS. The aims of this study were to identify, in pts planned for NAC, predictive parameters for attempting DS and for achieving optimal cytoreduction in those undergoing surgery. Methods: Pts with presumed stage IIIC or IV EOC who started NAC between 1998 and 2004 were selected for chart review from our institutional ovarian cancer database. Pts with synchronous primary tumors or final pathology inconsistent with EOC were excluded. Age, presence of ascites, Pre NAC hemoglobin (Hb), platelet count (Pls), and CA-125 were explored as possible predictors of attempting DS and of optimal cytoreduction using Kruskal-Wallis analysis and multivariate regression analysis with backward elimination. Results: 212 pts met inclusion criteria. 164 pts (77.4%) had an attempt at DS after NAC; of these 109 pts (66.4%) were optimally cytoreduced. Age and pre-NAC Pls were independent predictors for attempting DS. Median age of pts undergoing DS was 65 years (range 42–82 yrs) compared to 77 yrs (range 54–89 yrs) in those in whom there was no DS attempt, p < 0.01. Median pre NAC Pls of pts undergoing DS was 398 (range 220–685) *109/L, compared to 298 (178–519) for those not proceeding to DS, p < 0.001. Pre NAC Hb, CA125, and ascites were not predictors of DS. Among pts undergoing DS, age was the only independent predictor of optimal cytoreduction identified: median age of pts (optimal vs. suboptimal cytoreduction) was 57yrs (range 42–73 yrs) vs. 67 yrs (49–82yrs), p < 0.001. Presence of ascites, pre-NAC Hb, pre-NAC Pls, and pre-NAC CA-125 were not predictors of optimal cytoreduction. Conclusions: At our centre, pt age and pre-NAC Pls are independent predictors for attempting DS following NAC for advanced stage EOC. In pts undergoing DS age was the only independent predictor of optimal cytoreduction identified. Further investigation of these findings is warranted. No significant financial relationships to disclose.