EP925 Cytoreductive surgery in stage IIIC and IV epithelial ovarian cancer, a prospective cohort study

Introduction/Background The aim of this study is to estimate the proportion of patients with advanced ovarian cancer requiring radical surgery to achieve complete (no macroscopic residual disease) or optimal cytoreduction (residual diseaze less than 1 cm). Methodology Data were collected prospectively on consecutive patients undergoing elective cytoreductive surgery for epithelial ovarian cancer (FIGO stage IIIC/IV) at Poole Hospital NHS Trust, a tertiary referral cancer center in the United Kingdom from July 2016 to March 2018. Results Over a 33-month period, 84 patients consecutive patients underwent primary (n=45) or cytoreduction after 3 or 4 (n=33) or 6 cycles chemotherapy (n=6) [total n=39 in the neoadjuvant chemotherapy (NAC) group]. 32 patients underwent diahragmatic peritonectomy [26 in the primary debulking surgery (PDS) and 8 in the NAC group], 26 underwent bowel resection [22 in PDS, with 3 of them being total colectomies, and 5 in NAC, lymphadectomy (n=20), splenectomy (n=8 in PDS and n=1 in NAC group) and 21 additonal upper abdominal procedures performed, namely cholecystectomy, excision of disease from porta hepatis, lesser omentum, liver´s Glisson’s capsule, pylorous or duodenum.Complete and optimal cytoreduction was achieved in 60.98% and 25.61% respectively (combined rate 86.59%). Of interest, complete cytoreduction was achieved in 68.89% of patients with primary surgery, in contrast to 51.35% of patients in the NAC group. 5 patients (6.10%) underwent a futile laparotomy (3 in primary and 2 in NAC group).Without incorporating radical procedures, the combined rate of complete and optimal cytoreduction would have dropped to only 31.7%. Conclusion The majority of our patients required at least one radical surgical procedure to achieve complete cytoreduction emphasizing the importance of advanced surgical skills and effort in management of women with FIGO Stage IIIC and IV ovarian cancer. Disclosure Nothing to disclose.