Emily Shaw

RAS testing of colorectal carcinoma—a guidance document from the Association of Clinical Pathologists Molecular Pathology and Diagnostics Group

Analysis of colorectal carcinoma (CRC) tissue for KRAS codon 12 or 13 mutations to guide use of anti-epidermal growth factor receptor (EGFR) therapy is now considered mandatory in the UK. The scope of this practice has been recently extended because of data indicating that NRAS mutations and additional KRAS mutations also predict for poor response to anti-EGFR therapy. The following document provides guidance on RAS (i.e., KRAS and NRAS) testing of CRC tissue in the setting of personalised medicine within the UK and particularly within the NHS. This guidance covers issues related to case selection, preanalytical aspects, analysis and interpretation of such RAS testing.

Observer agreement comparing the use of virtual slides with glass slides in the pathology review component of the POSH breast cancer cohort study

Aims (1) To compare the use of scanned virtual slide images (virtual microscopy) with glass slides (conventional microscopy) in the assessment of morphological characteristics of breast cancers within the setting of the Prospective study of Outcomes in Sporadic versus Hereditary breast cancer (POSH), involving a cohort of women under 40 years of age, presenting with breast cancer. (2) To assess the acceptability to histopathologists of the use of virtual slide images. Methods 13 histopathologists from the UK and Australia participated in the POSH pathology review. The observers were asked to assess multiple morphological features such as tumour grade and type. Comparisons were made for a single observer using both virtual images and glass slides. Intra- and inter-observer variability was calculated using the κ statistic and a comparison was made between the use of each image modality. Results Diagnostic performance with virtual slides was comparable to conventional microscopic assessment, with the measurement of agreement best for vascular invasion, necrosis and the presence of a central scar (κ=0.37–0.78), and poor for more subjective parameters such as pleomorphism, stroma, the nature of the tumour border and the degree of lymphocytic infiltrate (κ=0.1). Conclusion Virtual slides represent an acceptable methodology for central review of breast cancer histopathology and can circumvent the need for either travel to view material, or the potential problems of sending it by post.

Evidence of mycobacterial disease in COPD patients with lung volume reduction surgery; the importance of histological assessment of specimens: a cohort study

BackgroundPatients with COPD are at risk of non-tuberculous mycobacterial infection (NTM). This study examined the histology of lung tissue from COPD patients following lung volume reduction with particular focus on evidence of mycobacterial infection.MethodsRetrospective histological study of 142 consecutive lung volume reduction surgical specimens (126 separate patients) at Royal Brompton Hospital between 2000 – 2013, with prospectively collected preoperative data on exacerbation rate, lung function and body mass index.Results92% of patients had at least one other histological diagnosis in addition to emphysema. 10% of specimens had histological evidence of mycobacterial infection, one with co-existent aspergilloma. Mycobacteria were only identified in those patients with granulomas that were necrotising. These patients had higher exacerbation rates, lower TLCO and FEV1.ConclusionA proportion of severe COPD patients will have evidence of mycobacterial infection despite lack of clinical and radiological suspicion. This may have implications for long-term management of these patients.

Lessons for molecular diagnostics in oncology from the Cancer Research UK Stratified Medicine Programme.

The implementation of stratified medicine in modern cancer care presents substantial opportunity to refine diagnosis and treatment but also numerous challenges. Through experience in a UK tumor profiling initiative, we have gained valuable insights into the complexities and possible solutions for routine delivery of stratified cancer medicine.

A collaborative approach to enabling stratified cancer medicine in the UK

Embedding stratified cancer medicine into the patient pathway will require adaptation of the diagnostic pathway to incorporate predictive molecular analysis, presenting challenges of accessing tumour samples of sufficient quality and quantity for analysis and ensuring the timeliness, accuracy, and clinical validity of results. In 2010, Cancer Research UK (CRUK), in partnership with AstraZeneca and Pfizer, set up the Stratified Medicine Programme (SMP1) to work collaboratively with a small number of hospital and genetics laboratories to demonstrate the feasibility of testing large volumes of samples, while working towards more standardised and efficient processes. By June 2013, 9010 patient samples had been sent for genetic testing and here we present an overview of our experience and the wealth of insights that have been generated into the complexities of attempting this transformation of National Health Service (NHS) care.

Crowdsourcing for translational research: analysis of biomarker expression using cancer microarrays

Background:Academic pathology suffers from an acute and growing lack of workforce resource. This especially impacts on translational elements of clinical trials, which can require detailed analysis of thousands of tissue samples. We tested whether crowdsourcing – enlisting help from the public – is a sufficiently accurate method to score such samples.Methods:We developed a novel online interface to train and test lay participants on cancer detection and immunohistochemistry scoring in tissue microarrays. Lay participants initially performed cancer detection on lung cancer images stained for CD8, and we measured how extending a basic tutorial by annotated example images and feedback-based training affected cancer detection accuracy. We then applied this tutorial to additional cancer types and immunohistochemistry markers – bladder/ki67, lung/EGFR, and oesophageal/CD8 – to establish accuracy compared with experts. Using this optimised tutorial, we then tested lay participants’ accuracy on immunohistochemistry scoring of lung/EGFR and bladder/p53 samples.Results:We observed that for cancer detection, annotated example images and feedback-based training both improved accuracy compared with a basic tutorial only. Using this optimised tutorial, we demonstrate highly accurate (>0.90 area under curve) detection of cancer in samples stained with nuclear, cytoplasmic and membrane cell markers. We also observed high Spearman correlations between lay participants and experts for immunohistochemistry scoring (0.91 (0.78, 0.96) and 0.97 (0.91, 0.99) for lung/EGFR and bladder/p53 samples, respectively).Conclusions:These results establish crowdsourcing as a promising method to screen large data sets for biomarkers in cancer pathology research across a range of cancers and immunohistochemical stains.

Somatic cancer genetics in the UK: real-world data from phase I of the Cancer Research UK Stratified Medicine Programme

Introduction Phase I of the Cancer Research UK Stratified Medicine Programme (SMP1) was designed to roll out molecular pathology testing nationwide at the point of cancer diagnosis, as well as facilitate an infrastructure where surplus cancer tissue could be used for research. It offered a non-trial setting to examine common UK cancer genetics in a real-world context. Methods A total of 26 sites in England, Wales and Scotland, recruited samples from 7814 patients for genetic examination between 2011 and 2013. Tumour types involved were breast, colorectal, lung, prostate, ovarian cancer and malignant melanoma. Centralised molecular testing of surplus material from resections or biopsies of primary/metastatic tissue was performed, with samples examined for 3–5 genetic alterations deemed to be of key interest in site-specific cancers by the National Cancer Research Institute Clinical Study groups. Results 10 754 patients (98% of those approached) consented to participate, from which 7814 tumour samples were genetically analysed. In total, 53% had at least one genetic aberration detected. From 1885 patients with lung cancer, KRAS mutation was noted to be highly prevalent in adenocarcinoma (37%). In breast cancer (1873 patients), there was a striking contrast in TP53 mutation incidence between patients with ductal cancer (27.3%) and lobular cancer (3.4%). Vast inter-tumour heterogeneity of colorectal cancer (1550 patients) was observed, including myriad double and triple combinations of genetic aberrations. Significant losses of important clinical information included smoking status in lung cancer and loss of distinction between low-grade and high-grade serous ovarian cancers. Conclusion Nationwide molecular pathology testing in a non-trial setting is feasible. The experience with SMP1 has been used to inform ongoing CRUK flagship programmes such as the CRUK National Lung MATRIX trial and TRACERx.

529 The Cancer Research UK Stratified Medicine Programme: From national screening to national trial

Background: The increasing demand for analysis of multiple predictive genetic markers in tumour samples to guide therapeutic decision-making requires the rapid validation and uptake of new knowledge and technology, as well as collaboration between clinical teams, cellular pathology and molecular genetics laboratories. Material and Methods: Between 2011 and 2013, formalin-fixed paraffinembedded tumour samples from patients consented through a network of hospitals underwent targeted mutation analysis. This was initially performed using Sanger sequencing and similar methods but following cross-validation an amplicon-based targeted next generation sequencing panel was implemented. Clinical information based on the requirements of the national cancer registration dataset was also centrally collated for each participant. The current second phase of the initiative has a sole focus on patients with advanced lung cancer, and aims to expand the geographical reach to perform molecular pre-screening of samples to help determine patient eligibility for the National Lung Matrix Trial, a multi-arm stratified phase II clinical trial of novel therapeutics. Results: 10,754 patients (98% of those approached) consented to analysis of material during phase one, with 9010 samples submitted for analysis. The table shows the overall results of analysis for the first 7850 samples. Analysis by histological subtype enriches for certain mutations, with 925 pulmonary adenocarcinomas showing 36.5% KRAS mutations, 11.6% EGFR mutations and 2.5% ALK gene rearrangements and 56 mucinous colorectal adenocarcinomas showing 43.5% BRAF mutations and 50% KRAS mutations. Conclusions: A centralised national testing network for genetic analysis of formalin-fixed paraffin-embedded tumour samples is feasible and acceptable to patients and clinicians, with applications beyond genotyping for currently licensed oncologic therapies. Acknowledgements: Funding for the Stratified Medicine Programme is acknowledged from Cancer Research UK and programme founding partners AstraZeneca and Pfizer.