Staging and Surgical Approaches in Gastric Cancer: A Clinical Practice Guideline

Background: Resection is the cornerstone of cure for gastric adenocarcinoma; however, several aspects of surgical intervention remain controversial or are suboptimally applied at a population level, including staging, extent of lymphadenectomy (LND), minimum number of lymph nodes that have to be assessed, gross resection margins, use of minimally invasive surgery, and relationship of surgical volumes with patient outcomes and resection in stage IV gastric cancer. Methods: Literature searches were conducted in databases including MEDLINE (up to 10 June 2016), EMBASE (up to week 24 of 2016), the Cochrane Library and various other practice guideline sites and guideline developer Web sites. A practice guideline was developed. Results: One guideline, seven systematic reviews, and forty-eight primary studies were included in the evidence base for this guidance document. Seven recommendations are presented. Conclusions: All patients should be discussed at a multidisciplinary team meeting, and computed tomography (CT) imaging of chest and abdomen should always be performed when staging patients. Diagnostic laparoscopy is useful in the determination of M1 disease not visible on ct images. A D2 LND is preferred for curative-intent resection of gastric cancer. At least 16 lymph nodes should be assessed for adequate staging of curative-resected gastric cancer. Gastric cancer surgery should aim to achieve an R0 resection margin. In the metastatic setting, surgery should be considered only for palliation of symptoms. Patients should be referred to higher-volume centres and those that have adequate support to manage potential complications. Laparoscopic resections should be performed to the same standards as those for open resections, by surgeons who are experienced in both advanced laparoscopic surgery and gastric cancer management

Maternal and neonatal outcomes in pregnancies following colorectal cancer

Background: The risks of adverse obstetric outcomes among young women survivors of colorectal cancer (CRC) are uncertain. Methods: This Western Australian, whole-jurisdictional linked-data, retrospective cohort study compared maternal and neonatal outcomes of first postcancer pregnancies among women CRC survivors against randomly selected pregnancies of women with no cancer history. Logistic regression models were used to investigate a range of adverse outcomes independently associated with CRC and its surgical and adjunctive treatments. Results: Among 627,762 deliveries during the study period (1983-2007), 232 were first pregnancies following CRC. Whether following laparoscopic or open cancer surgery, these pregnancies were independently associated with a significantly increased risk of antepartum hemorrhage [odds ratios (ORs): 1.25; 2.13 for the respective procedures], postpartum hemorrhage (ORs: 1.61; 3.31), Cesarean delivery (ORs: 2.42; 4.24), infant low Apgar score (ORs: 1.32; 2.64), need for neonatal resuscitation (ORs: 1.49; 3.20), and special care admission (ORs: 1.42; 2.87). A history of open (but not laparoscopic) cancer surgery was associated with increased risk of gastrointestinal obstruction during pregnancy (OR 1.17) and prolonged postpartum hospitalization (OR 3.11). Neither was significantly associated with perinatal death. Among women with previous CRC, rectal (versus colonic) malignancy was independently associated with a significantly higher risk of overall maternal and neonatal adverse outcomes (ORs: 3.73 and 2.73, respectively), as was radiotherapy (ORs: 4.24 and 2.81, respectively). Chemotherapy was independently associated with a marginally but significantly higher risk of overall maternal but not neonatal outcomes (ORs: 1.11; 0.98). Open versus laparoscopic cancer surgery was associated with a significantly higher risk of antepartum and postpartum hemorrhage, low Apgar score, need for neonatal resuscitation, and neonatal special care admission. Conclusions: Previous CRCs, particularly rectal and radiation-treated tumors, appear to confer an increased likelihood of adverse outcomes in subsequent pregnancies. Laparoscopic technique for CRC surgery may reduce adverse gestational outcomes. © 2013 Springer Science+Business Media New York

In-situ large scale deposition of PZT films by RF magnetron sputtering

In the present study, high quality PZT films were deposited by RF magnetron sputtering onto 200mm thermally oxidized silicon substrates at substrate holder temperatures (Th) between 550°C - 700°C using PbO-enriched single ceramic PZT targets. The high substrate temperatures used here allowed direct growth of the piezoelectric perovskite phase and rendered an additional post annealing step unnecessary. The PZT layers were grown on (111) oriented Pt bottom electrodes, which were covered by thin TiO2 seed layers. Over the temperature range investigated here, there was a monotonic reduction in the Pb/(Zr+Ti) atomic ratio with increasing Th; the stoichiometry of the morphotropic phase boundary Pb/(Zr+Ti) 1 and Zr/(Zr+Ti) 0.53 was obtained at 700°C. However, the XRD patterns indicated that the films prepared at intermediate Th = 600°C exhibited the minimum volume fraction of the spurious pyrochlore phase in addition to tetragonal and rhombohedral piezoelectric PZT structure s. All PZT films contained mixed (110), (111) and (200) crystallographic orientations whose relative intensities were significantly influenced by Th. The highest piezoelectric coefficients d33,f = 120 pm/V and e31,f = -12.6 C/m 2 were obtained for the films deposited at Th = 600°C

Electrical Properties of Thin-Film Capacitors Fabricated Using High Temperature Sputtered Modified Barium Titanate

Simple thin-film capacitor stacks were fabricated from sputter-deposited doped barium titanate dielectric films with sputtered Pt and/or Ni electrodes and characterized electrically. Here, we report small signal, low frequency capacitance and parallel resistance data measured as a function of applied DC bias, polarization versus applied electric field strength and DC load/unload experiments. These capacitors exhibited significant leakage (in the range 8–210 μA/cm2) and dielectric loss. Measured breakdown strength for the sputtered doped barium titanate films was in the range 200 kV/cm −2 MV/cm. For all devices tested, we observed clear evidence for dielectric saturation at applied electric field strengths above 100 kV/cm: saturated polarization was in the range 8–15 μC/cm2. When cycled under DC conditions, the maximum energy density measured for any of the capacitors tested here was ~4.7 × 10−2 W-h/liter based on the volume of the dielectric material only. This corresponds to a specific energy of ~8 × 10−3 W-h/kg, again calculated on a dielectric-only basis. These results are compared to those reported by other authors and a simple theoretical treatment provided that quantifies the maximum energy that can be stored in these and similar devices as a function of dielectric strength and saturation polarization. Finally, a predictive model is developed to provide guidance on how to tailor the relative permittivities of high-k dielectrics in order to optimize their energy storage capacities

Sputtered Modified Barium Titanate for Thin-Film Capacitor Applications

New apparatus and a new process for the sputter deposition of modified barium titanate thin-films were developed. Films were deposited at temperatures up to 900 °C from a Ba0.96Ca0.04Ti0.82Zr0.18O3 (BCZTO) target directly onto Si, Ni and Pt surfaces and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Film texture and crystallinity were found to depend on both deposition temperature and substrate: above 600 °C, the as-deposited films consisted of well-facetted crystallites with the cubic perovskite structure. A strongly textured Pt (111) underlayer enhanced the (001) orientation of BCZTO films deposited at 900 °C, 10 mtorr pressure and 10% oxygen in argon. Similar films deposited onto a Pt (111) textured film at 700 °C and directly onto (100) Si wafers showed relatively larger (011) and diminished intensity (00ℓ) diffraction peaks. Sputter ambients containing oxygen caused the Ni underlayers to oxidize even at 700 °C: Raising the process temperature produced more diffraction peaks of NiO with increased intensities. Thin-film capacitors were fabricated using ~500 nm thick BCZTO dielectrics and both Pt and Ni top and bottom electrodes. Small signal capacitance measurements were carried out to determine capacitance and parallel resistance at low frequencies and from these data, the relative permittivity (er) and resistivity (r) of the dielectric films were calculated; values ranged from ~50 to >2,000, and from ~104 to ~1010 Ω∙cm, respectively