Abstract P1-05-16: An integrated molecular analysis of invasive lobular carcinoma

Background: Invasive lobular carcinoma (ILC) is the most commonly diagnosed special histological type of breast cancer, accounting for up to 15% of all cases. Accumulating data suggests the biology and clinical features of ILC differ to those of the more commonly diagnosed Invasive Carcinoma of No Special Type (IC-NST), including evidence of there being an overall worse long term outcome associated with ILC. Several large-scale molecular profiling studies have recently been published regarding ILC, highlighting molecular heterogeneity and important drivers of tumour behaviour. We hypothesize that an integrative analysis of gene expression and DNA copy number data will identify novel drivers, and prognostic and predictive biomarkers of lobular phenotype.

Methods: Gene expression and copy number data from ILC tumours profiled in-house (n=25), METABRIC (n=125) and TCGA (n=145) were assembled and analysed. Integration of genome and transcriptome data was performed using two methods. Firstly, by Spearman correlation with a meta-analysis by combining gene level correlation coefficients from each study using a random effects model, weighting each study with inverse variance. Secondly using ANOVA, followed by combining gene level p-values across studies using Stouffers Z-score. Disease specific survival was examined at an individual gene level and using all genes simultaneously (via a Cox Boost analysis) to identify gene expression changes that are associated with poor outcome.

Results: DNA copy number profiling identified recurrent gains (1q, 8q, 16p), losses (11q, 16q) and amplifications (1q32, 8p12-p11.2, 11q13). 11q13 amplifications were prevalent at a higher frequency in patients with poor outcome compared to patients with better outcome. The integrative analysis identified 1928 candidate genes whose expression was associated with gene copy number; as expected being enriched from genome regions highlighted above. One hundred and sixty of these genes were of prognostic significance in the METABRIC ILC cohort, several are known cancer drivers (e.g. PBX1, CCND1) and five new candidates are being investigated as novel prognostic biomarkers by immunohistochemistry.

Conclusions: An integrated molecular analysis of ILC has identified a large number of gene expression changes that are dictated by gene copy number in ILC. Some of these are expected to influence tumour behavior and to highlight aggressive cancers with poor prognosis.

Citation Format: Lal S, McCart Reed A, Nones K, Wockner L, Song S, Lakhani S, Simpson P. An integrated molecular analysis of invasive lobular carcinoma [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-05-16.

A novel method for isolation and recovery of ceramic nanoparticles and metal wear debris from serum lubricants at ultra-low wear rates

Ceramics have been used to deliver significant improvements in the wear properties of orthopaedic bearing materials, which has made it challenging to isolate wear debris from simulator lubricants. Ceramics such as silicon nitride, as well as ceramic-like surface coatings on metal substrates have been explored as potential alternatives to conventional implant materials. Current isolation methods were designed for isolating conventional metal, UHMWPE and ceramic wear debris. In this paper, we describe a methodology for isolation and recovery of ceramic or ceramic-like coating particles and metal wear particles from serum lubricants under ultra-low and low wear performance. Enzymatic digestion was used to digest the serum proteins and sodium polytungstate was used as a novel density gradient medium to isolate particles from proteins and other contaminants by ultracentrifugation. This method demonstrated over 80% recovery of particles and did not alter the size or morphology of ceramic and metal particles during the isolation process.

STATEMENT OF SIGNIFICANCE

Improvements in resistance to wear and mechanical damage of the articulating surfaces have a large influence on longevity and reliability of joint replacement devices. Modern ceramics have demonstrated ultra-low wear rates for hard-on-hard total hip replacements. Generation of very low concentrations of wear debris in simulator lubricants has made it challenging to isolate the particles for characterisation and further analysis. We have introduced a novel method to isolate ceramic and metal particles from serum-based lubricants using enzymatic digestion and novel sodium polytungstate gradients. This is the first study to demonstrate the recovery of ceramic and metal particles from serum lubricants at lowest detectable in vitro wear rates reported in literature.

Medical complications of anorexia nervosa

Anorexia nervosa is a psychiatric disorder with potential life-threatening medical sequelae. This article reviews the principal medical complications associated with anorexia nervosa, highlights associated diagnostic pitfalls and emphasizes the importance of a multidisciplinary approach to management.

Quality and safety impact on the provision of parenteral nutrition through introduction of a nutrition support team

BACKGROUND/OBJECTIVES

Parenteral nutrition (PN) should be provided to the malnourished patient if enteral feeding is insufficient or unsafe. A nutrition support team (NST) may improve PN services. We compared the use and complications of hospital PN before and after the implementation of an NST.

SUBJECTS/METHODS

All inpatients referred for PN outside of the intensive care unit and the intestinal failure unit were prospectively included from 2009 to 2012. The NST was introduced in 2010. Quality improvement methodology was applied.

RESULTS

In 2009, a mean of 16 (limits of normal variation 4-28) patients were referred for PN each month. After introduction of the NST, this rose to 26 (10-42) referrals per month. The percentage of referrals where PN was not initiated increased from 5.3% in 2009 to 10.1% in 2012 (P=0.03). This increase was restricted to teams that infrequently referred for PN, and enteral nutrition could replace PN in 31 of 51 patients (61%) as compared with 8 of 32 (25%) patients referred from teams that frequently referred for PN (P=0.001). The frequency of PN started owing to an insufficient oral or enteral intake decreased from 11% to 3% (P=0.01). The catheter-related bloodstream infection rate dropped from 6.7 to 0.7 episodes per 1000 catheter days (P<0.001).

CONCLUSIONS

Introduction of an NST increased both the total PN use and the percentage of referrals where enteral nutrition could replace PN. Medical specialty influenced the referral pattern and the likelihood that a referral resulted in PN being initiated. Safety of PN catheters improved significantly following NST introduction.