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Background: The current therapy of ovarian cancer is based on the so-called “Three-Pillar-Model”, consisting of surgery, chemotherapy and maintenance therapy. This study represents the first major analysis of a federal cancer database of OC patients from the states Berlin/Brandenburg in Germany. The primary objective was to evaluate the prevailing established quality indicators surgical outcome, adjuvant chemotherapy and integrity of surgical staging in early stages. Methods: Data from the Clinical Cancer Registry for Brandenburg and Berlin of the years 2009–2019 were analyzed. Objectives were defined by a working group of selected physicians. Descriptive statistics were performed, as well as survival analysis. Results: A total of 2771 primary OC cases were included. Results regarding histological subtype met the suspected allocation with predominantly high-grade serous OC in advanced stage. The rate of complete surgical staging in FIGO stages I–IIA was 57%, and the rate of macroscopic complete resection in >FIGO III was 53%. Five-year survival rate varied from 79% (FIGO I) to 40% (FIGO III). Rate of adjuvant chemotherapy was above 50%. Conclusion: The results elucidate quality measurements and treatment results and show good treatment outcomes in patients with primary diagnosis. However, they also indicate deficits and can help to establish new quality indicators to further improve the treatment.

BACKGROUND Occlusions of artificial small-diameter cardiovascular grafts are frequent events after implantation, often caused by clot formations. A main factor is the insufficient hemocompatibility of the inner artificial graft surface, which could be improved by endothelialization. Therefore, one challenge in cardiovascular graft engineering is the establishment of a shear-resistant endothelial cell layer to prevent cell detachment by shear forces after implantation. MATERIALS AND METHODS Recently, very smooth (Rq = 2.37 ± 1.40 nm) poly(ether imide) (PEI) films were introduced as a biocompatible candidate material for cardiovascular devices. In this study the stability of primary human umbilical vein endothelial cell (HUVEC) monolayer was investigated after long-term seeding (nine days) on PEI-films and subsequent exposure to a venous shear stress of 3 dyn/cm2 for up to six hours using the cone-and-plate shearing technique. Cell density, growth pattern and morphology of HUVEC were determined prior and after shearing compared to glass as control substrate. HUVEC adhering to the substrate after shear stress were counted and analyzed by fluorescent staining. Supernatants were collected and secretion profile analysis of vasoactive and inflammatory mediators was performed. RESULTS The cell density on PEI-films compared to the controls was slightly higher after long-term seeding and exposure to shear stress (glass: 71,656 ± 8,830 cells/cm2 and 42,239 ± 5,607 cells/cm2; PEI-film: 64,056 ± 2,829 cells/cm2 and 45,422 ± 2,507 cells/cm2 before and after shear stress, respectively). Actin- and vinculin-staining revealed a scattered re-organization of the cytoskeleton as well as a formation of stress fibers and focal adhesion points. Secretion of prostacyclin and thromboxane A2 was increased after application of shear stress, but no significant differences were detectable between cells growing on PEI-films or glass. Amounts of secreted inflammatory cytokines IL-6 and IL-8 in the supernatant were significantly lower for HUVEC seeded on PEI-films compared to glass before as well as after stress. CONCLUSION The study demonstrated that HUVEC were able to resist exposure to venous shear stress when seeded on smooth PEI-films with typical morphology and adhesion behavior. However, HUVEC adherence on PEI was not yet sufficient to retain a complete cell monolayer after shear stress exposure. Occasionally, single cells or cell plaques were disrupted resulting in cell free areas in the confluent HUVEC layer. Apart from this our data suggest that PEI is a suitable substrate for HUVEC under static and dynamic conditions and therefore a promising candidate material for cardiovascular applications. The next objective is a surface functionalization of the PEI-films in a cell specific manner to reach a functionally confluent, shear resistant HUVEC monolayer.

The chain length and end groups of linear PEG grafted on smooth surfaces is known to influence protein adsorption and thrombocyte adhesion. Here, it is explored whether established structure function relationships can be transferred to application relevant, rough surfaces. Functionalization of poly(ether imide) (PEI) membranes by grafting with monoamino PEG of different chain lengths (M-n=1kDa or 10kDa) and end groups (methoxy or hydroxyl) is proven by spectroscopy, changes of surface hydrophilicity, and surface shielding effects. The surface functionalization does lead to reduction of adsorption of BSA, but not of fibrinogen. The thrombocyte adhesion is increased compared to untreated PEI surfaces. Conclusively, rough instead of smooth polymer or gold surfaces should be investigated as relevant models.

Poly(ether imide) (PEI) is being explored as potential biomaterial for cardiovascular applications. Different studies showed that human umbilical venous endothelial cells (HUVEC) are able to adhere and proliferate on PEI membranes (R(q) = 13.20 ± 1.58 nm). A recently published study revealed evidence for much lower platelet adhesion on very smooth PEI-films (R(q) = 2.37 ± 1.40 nm). Therefore, we explored whether primary human venous endothelial cells (HUVEC) are able to adhere and proliferate on such very smooth PEI-films compared to tissue-cultured polystyrene (TCP) as reference material. Cytotoxicity testing revealed that PEI had a slight cytotoxic effect on HUVEC accompanied by a marginal reduced integrity of the plasma membrane and a significant lower mitochondrial activity. However long-term seeding experiments up to eleven days exhibited that HUVEC were able to proliferate on the PEI-films till confluence (TCP 96,190 ± 18,289 cells/cm(2); PEI 91,590 ± 19,583 cells/cm(2)). Further studies are planned to monitor the influence of shear force on the endothelial cell monolayer in a dynamic test system to determine its stability in view of shear resistant endothelialization of PEI for cardiovascular devices.