Main aim of this study is to assess the effect of a structured, interdisciplinary, surgical, team-training protocol in robotic gynecologic surgery, with the gradual integration of an advanced nurse practitioner. Data from all robotic surgical procedures were prospectively acquired. The surgical team consisted of one experienced surgeon and two surgical fellows and the scrub nurse team from three advance nurse practitioners, specialized in robotic surgery. The training was performed in a four-phase manner over 4 years and included theoretical training, hands-on training and team-communication skills enhancement. Scrub nurses increasingly adopted an active role during surgery. For a period of 4 years, 175 patients could be included in the analysis. All of them underwent a robotic gynecologic procedure. Mean docking time decreased from 45.3 to 27.3 min (p < 0.001), mean operating time from 235 to 179 min (p = 0.0071) and costs per case from 17,891 to 14,731 Swiss Francs (p = 0.035). There were no statistically significant changes in perioperative complications and conversions to laparotomy. An interdisciplinary long-term training protocol for high specialized robotic surgery within a “fixed” team with the gradually addition of an advanced study nurse improves the efficacy of the procedure in terms of time and costs. Although the surgery is performed quicker, the same performance and quality of surgical care could be reached.

Abstr Ac tFetal cholelithiasis is a rare finding during a third-trimester ultrasound with an average incidence rate of 0.07-1.15 %. We report a case of fetal cholelithiasis in twins, observed in a patient with monochorionic diamniotic twin pregnancy hospitalized at our unit for signs of premature labor. We present the outcome of the 2 neonates with a clinical and sonographic follow-up. In addition, we offer a comprehensive review of the literature available to date.

5515 Background: Ovarian cancer (OC) is mostly diagnosed as G3 serous advanced stage disease with survival of only 20% in 5 years. Maintenance therapy after 1st line chemotherapy is increasingly used, particularly with Bevacizumab or PARP inhibitors. However, the effect of antihormonal treatment in breast cancer but also in relapsed gynecological cancers has been shown. Also in low grade OC, data are highly supportive of antihormonal treatment. In a previous study of ours, also high grade serous cancers express high amounts of estrogen receptor (ER). The aim of this study was to analyze whether a maintenance antihormonal therapy in advanced OC adds a benefit in relation to the time of recurrence. Methods: All newly diagnosed G3 FIGO III/IV OC cases at our Hospital were assessed prospectively for ER expression. Patients with positive ER status (> 10%) were treated as maintenance therapy with Letrozol 2.5mg 1x/d or not. Progression free survival was recorded and analyzed according to Kaplan-Meier. Patients with macroscopic residual disease post surgery receiving Bevacizumab maintenance treatment were also included. Results: We identified 51 patients with G3 serous OC FIGO III/IV expressing ER. Hereby, 24 patients received and 27 patients did not receive Letrozol after adjuvant chemotherapy. Time to progression ranged from 4 to 121 months. The use of Letrozol was associated with a significant prolonged progression free interval. After 12 months, only 65% of women in the control group vs 84% in the Letrozol group were progression-free. After 24 months, the effect was even stronger (46% in the control group vs 74% with Letrozol (p= 0.02)). Within the subgroup of patients with residual disease treated with Bevacizumab a similar effect was seen with 41% of patients progression free after 12 months vs 89% when taking Letrozol in addition to Bevacizumab. Conclusions: The use of Letrozol as a maintenance therapy after the 1st line treatment in G3 advanced stage serous OC patients was associated with a longer recurrence free interval in our cohort. These findings warrant a randomized controlled trial comparing all existing maintenance regimen as this might have a major influence on cost development in OC treatment.

however markers that further risk-stratify intermediate groups are needed. Serum cancer antigen-125 (CA125) and human epididymis-4 (HE4) show promise as prognostic markers. The aim of this study was to evaluate the association between serum CA125, HE4 and endometrial cancer survival outcomes when stratified by molecular subgroup. Methodology Pre-treatment serum CA125 and HE4 levels were measured and endometrial tumours classified according to WHO molecular classification. The relationship between biomarkers and survival was evaluated using Kaplan-Meier analysis and multivariable cox regression. Results Overall, 327 women were included, with POLE status available for 216. Tumours were POLE-mutant (5%), p53abnormal (11%), MMR-deficient (30%) and NSMP (54%). Median follow up was 50 months (IQR 30-60), during which 42 (13%) recurred and 71 (21%) women died. CA12535U/mL was independently associated with overall mortality [aHR=2.42 (95%CI:1.45-4.06), p=0.001), cancer specific death [aHR=2.00 (95%CI:1.04-3.87), p=0.04] and recurrence [aHR=2.69 (95%CI:1.38-5.27), p=0.004]. When stratified by molecular subgroup, CA12535U/mL and HE4150pmol/L were prognostic of overall survival in p=0.01] and NSMP subgroups [CA125: aHR=3.72 (95%CI:1.30-10.67), p=0.01)]. Conclusion CA125 and HE4 may risk-stratify those at intermediate risk of recurrence and death. Evaluation in a larger population is required.

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