Metal Oxide Nanosheets as 2D Building Blocks for the Design of Novel Materials

Research into 2-dimensional materials has soared during the last couple of years. Next to van der Waals type 2D materials such as graphene and h-BN, less well-known oxidic 2D equivalents also exist. Most 2D oxide nanosheets are derived from layered metal oxide phases, although few 2D oxide phases can be also made by bottom-up solution syntheses. Owing to the strong electrostatic interactions within layered metal oxide crystals, a chemical process is usually needed to delaminate them into their 2D constituents. This Review article provides an overview of the synthesis of oxide nanosheets, and methods to assemble them into nanocomposites, mono- or multilayer films. In particular, the use of Langmuir–Blodgett methods to form monolayer films over large surface areas, and the emerging use of ink jet printing to form patterned functional films is emphasized. The utilization of nanosheets in various areas of technology, for example, electronics, energy storage and tribology, is illustrated, with special focus on their use as seed layers for epitaxial growth of thin films, and as electrochemically active electrodes for supercapacitors and Li ion batteries.</p

The management of women with ductal carcinoma in situ of the breast in Australia and New Zealand between 2007 and 2016

Background: The incidence of detected ductal carcinoma in situ (DCIS) continues to increase and now accounts for 14% of all breast cancer, and 20%–25% of screen-detected cases. Treatment trends of DCIS are important in order to inform the ongoing debate about possible overdiagnosis and overtreatment, but have not been investigated for over a decade in Australia and New Zealand. Against this background, we aimed to describe the temporal trends in management of DCIS in Australian and New Zealander women. Methods: Using the BreastSurgANZ Quality Audit (BQA) database, we conducted a descriptive study of the trends of management of DCIS in Australia and New Zealand from 2007 to 2016. We assessed the frequency of surgical treatments, adjuvant therapies, and axillary surgery conducted in women with pure DCIS. Results: There were 17 883 cases of pure DCIS in 2007–2016 in Australia and New Zealand recorded in the BQA database. The treatment patterns were consistent with no changes over time. The most common surgical treatment was breast-conserving surgery (66%), followed by mastectomy (37%), and 36% of women with DCIS received sentinel node biopsy (SNB). Conclusion: The clinical management of women diagnosed with DCIS in Australia and New Zealand, appears stable over time. A substantial proportion of women with DCIS receive SNB and this aspect of surgical care warrants further exploration to determine whether it represents appropriate care. These results, alongside the outcomes of the ongoing clinical trials on the management of DCIS, will help inform if any changes to best practice treatment are required.Sofia Omling, Nehmat Houssami, Kevin McGeechan, Sophia Zackrisson, Gemma Jacklyn, David Walters, Alexandra Barratt, and Rachel Farbe

A prediction model for underestimation of invasive breast cancer after a biopsy diagnosis of ductal carcinoma in situ: based on 2892 biopsies and 589 invasive cancers

Background: Patients with a biopsy diagnosis of ductal carcinoma in situ (DCIS) might be diagnosed with invasive breast cancer at excision, a phenomenon known as underestimation. Patients with DCIS are treated based on the risk of underestimation or progression to invasive cancer. The aim of our study was to expand the knowledge on underestimation and to develop a prediction model. Methods: Population-based data were retrieved from the Dutch Pathology Registry and the Netherlands Cancer Registry for DCIS between January 2011 and June 2012. Results: Of 2892 DCIS biopsies, 21% were underestimated invasive breast cancers. In multivariable analysis, risk factors were high-grade DCIS (odds ratio (OR) 1.43, 95% confidence interval (CI): 1.05–1.95), a palpable tumour (OR 2.22, 95% CI: 1.76–2.81), a BI-RADS (Breast Imaging Reporting and Data System) score 5 (OR 2.36, 95% CI: 1.80–3.09) and a suspected invasive component at biopsy (OR 3.84, 95% CI: 2.69–5.46). The predicted risk for underestimation ranged from 9.5 to 80.2%, with a median of 14.7%. Of the 596 invasive cancers, 39% had unfavourable features. Conclusions: The risk for an underestimated diagnosis of invasive breast cancer after a biopsy diagnosis of DCIS is considerable. With our prediction model, the individual risk of underestimation can be calculated based on routinely available preoperatively known risk factors (https://www.evidencio.com/models/show/1074)

Epitaxial lift-off of freestanding (011) and (111) SrRuO3 thin films using a water sacrificial layer

Two-dimensional freestanding thin films of single crystalline oxide perovskites are expected to have great potential in integration of new features to the current Si-based technology. Here, we showed the ability to create freestanding single crystalline (011)- and (111)-oriented SrRuO3 thin films using Sr3Al2O6 water-sacrificial layer. The epitaxial Sr3Al2O6(011) and Sr3Al2O6(111) layers were realized on SrTiO3(011) and SrTiO3(111), respectively. Subsequently, SrRuO3 films were epitaxially grown on these sacrificial layers. The freestanding single crystalline SrRuO3(011)pc and SrRuO3(111)pc films were successfully transferred on Si substrates, demonstrating possibilities to transfer desirable oriented oxide perovskite films on Si and arbitrary substrates

Shape Control of Ca2Nb3O10 Nanosheets: Paving the Way for Monolithic Integration of Functional Oxides with CMOS

In order to integrate functional oxides with Complementary Metal Oxide Semiconductor (CMOS) materials, templates to ensure their epitaxial growth are needed. Although oxide nanosheets can be used to direct the thin film growth of transition metal oxides in a single out-of-plane orientation, the in-plane orientation of individual nanosheets within a nanosheet-based film is totally random. Here, we show the ability to improve the in-plane orientation of Ca2Nb3O10 nanosheets, and hence of SrRuO3 films grown on them by controlling their external shape. The parent-layered perovskite KCa2Nb3O10 particles were formed in square-like platelets, thanks to the anisotropic growth in molten K2SO4 salt, as opposed to the formation of irregular platelets in a solid-state reaction. The exfoliation of HCa2Nb3O10, which is the protonated form of KCa2Nb3O10, was optimized to retain the square-like shape of Ca2Nb3O10 nanosheets. Electron backscatter diffraction confirmed the improved in-plane orientation among square-like Ca2Nb3O10 nanosheets with the formation of larger SrRuO3 domains. As a result, SrRuO3 films showed the lower resistivity and higher residual resistivity ratio, ρ300K/ρ2K, on square-like Ca2Nb3O10 nanosheets than on irregularly shaped nanosheets of similar lateral nanosheet size

Epitaxial lift-off of freestanding (011) and (111) SrRuO3 thin films using a water sacrificial layer

AbstractTwo-dimensional freestanding thin films of single crystalline oxide perovskites are expected to have great potential in integration of new features to the current Si-based technology. Here, we showed the ability to create freestanding single crystalline (011)- and (111)-oriented SrRuO3 thin films using Sr3Al2O6 water-sacrificial layer. The epitaxial Sr3Al2O6(011) and Sr3Al2O6(111) layers were realized on SrTiO3(011) and SrTiO3(111), respectively. Subsequently, SrRuO3 films were epitaxially grown on these sacrificial layers. The freestanding single crystalline SrRuO3(011)pc and SrRuO3(111)pc films were successfully transferred on Si substrates, demonstrating possibilities to transfer desirable oriented oxide perovskite films on Si and arbitrary substrates.</jats:p

Abstract P5-16-02: Risk of subsequent ipsilateral invasive breast cancer after a primary diagnosis of ductal carcinoma in situ

Abstract Background Since the introduction of population-based mammography screening the incidence of ductal carcinoma in situ of the breast (DCIS) has increased dramatically and concerns about overdiagnosis and overtreatment have been raised. DCIS is considered to be a precursor lesion of most invasive breast cancer, but the challenge remains to distinguish the progressive from the clinically indolent, i.e. harmless lesions. Therefore, we aim to assess the risk of developing a subsequent ipsilateral invasive breast cancer after a first cancer diagnosis of primary DCIS in a large cohort as a first step to solve this clinical dilemma. Methods We conducted a retrospective study using a nationwide cohort comprising 12,721 women with a first cancer diagnosis of breast carcinoma in situ in the Netherlands between 1 January 1989 and 31 December 2004 and follow-up data up to 31 December 2010, extracted from the Netherlands Cancer Registry (NCR). Women who had bilateral breast disease, a diagnosis other than pure DCIS, and patients who received chemo- or hormonal therapy for their DCIS were excluded, as well as patients who had any other previous cancer diagnosis except for non-melanoma skin carcinoma. Using data from NCR and PALGA, the Dutch Pathology Registry, information about treatment and outcomes was collected and analysed. Outcome was defined as a subsequent ipsilateral invasive breast cancer as first invasive recurrence. Women who had a contralateral invasive breast cancer first, were censored at this diagnosis date. Invasive recurrence rates were compared by age and treatment groups using Cox regression. Women were divided into three age groups: women who were within the age group eligible for participation in the Dutch screening programme, and women who were either younger or older. Results A total number of 10,276 women with pure DCIS were included. After a median follow-up of 11.6 years, 520 first ipsilateral invasive recurrences were identified. Preliminary results show that approximately half of the women were treated with breast-conserving surgery (BCS), and the other half underwent a mastectomy. Of the patients who underwent BCS, about half received additional radiotherapy (RT). The age-adjusted hazard ratio for ipsilateral invasive breast cancer in BCS only versus BCS + RT was 2.49 (95% CI: 1.99 – 3.12) and in mastectomy versus BCS + RT 0.32 (95% CI: 0.24 - 0.43). After adjusting for treatment, risk of subsequent ipsilateral invasive breast cancer was higher for women who were younger than the invitation age range for screening when diagnosed compared to women within the age group eligible for the Dutch screening programme (HR = 1.86; 95% CI: 1.51 – 2.29). Conclusion This unique nationwide DCIS cohort shows that young women and women treated with BCS only have an increased risk of developing a subsequent ipsilateral invasive breast cancer after a first cancer diagnosis of primary DCIS. Using this cohort with a large number of women with subsequent ipsilateral invasive breast cancer, we will subsequently evaluate the concordance of features of the primary DCIS and the subsequent invasive breast cancer, and the association of characteristics of the DCIS with the risk of developing invasive ipsilateral breast cancer. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-16-02.</jats:p

Abstract P5-17-06: Prognostic value of method of detection in primary pure DCIS

Abstract Background Population-based mammographic screening programs have led to a substantial increase in incidence of ductal carcinoma in situ (DCIS). We assessed whether the method of detection provides prognostic information among women with DCIS detected through the Dutch screening program (screen-detected DCIS) and those with DCIS not detected within the national screening program (non-screen-detected DCIS). This could have impact on the treatment strategy of screen-detected DCIS as compared to symptomatic DCIS. Methods We studied a population-based retrospective cohort comprising 7,106 women aged 49-76 years with primary pure DCIS, who were treated by mastectomy or breast conserving surgery with or without radiotherapy between 1989 and 2004 in the Netherlands. Risk of subsequent ipsilateral and contralateral invasive breast cancer and overall survival among women with screen-detected (n=4,905) and non-screen-detected (n=2,201) DCIS were compared using Cox regression, adjusting for treatment (time-dependent), age (time-scale), diagnosis period and follow-up duration. Because of gradual implementation of the screening program in the Netherlands, we defined two periods based on year of DCIS diagnosis: 1989-1998 (gradual implementation of screening) and 1999-2004 (full coverage of screening). Results With a median follow-up of 10.5 years (interquartile range 7.7-14.0 years) 366 ipsilateral (screen-detected DCIS n=234, non-screen-detected DCIS n=132) and 380 contralateral (screen-detected DCIS n=245, non-screen-detected DCIS n=135) invasive breast cancers were diagnosed, and 1,088 of 7,106 women died (screen-detected DCIS n=603, non-screen-detected DCIS n=485). From 1989 to 2004 the number of non-screen-detected DCIS remained stable (mean 140, range 110-187 per year), whereas the number of screen-detected primary pure DCIS increased from 8 in 1989 to 596 in 2004. Ipsilateral invasive breast cancer risk was lower for screen-detected DCIS compared to DCIS not detected within the national screening program, irrespective of DCIS treatment, period of diagnosis, and follow-up duration (adjusted hazard ratio [HR] 0.74, 95% confidence interval [CI] 0.59-0.92, p &amp;lt; 0.01). The prognostic value of method of detection was similar across categories of treatment, period of diagnosis, and follow-up duration. The risk of contralateral invasive breast cancer did not differ between screen-detected DCIS and non-screen-detected DCIS (adjusted HR 0.89, 95% CI 0.71-1.11, p = 0.3) and neither did all-cause mortality (adjusted HR 0.91, 95% CI 0.79-1.04, p = 0.2). Conclusion Women with primary pure DCIS detected through the Dutch screening program had lower risk of subsequent ipsilateral invasive breast cancer, irrespective of DCIS treatment, compared to women whose DCIS was not detected within the national screening program. However, the magnitude of this risk difference does not warrant a different treatment strategy of screen-detected DCIS as compared to non-screen-detected DCIS. Having a screen-detected DCIS was not associated with risk of subsequent contralateral invasive breast cancer and all-cause mortality. Citation Format: Elshof LE, Schaapveld M, Schmidt MK, van Leeuwen FE, Rutgers EJTh, Wesseling J. Prognostic value of method of detection in primary pure DCIS. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-17-06.</jats:p