Diagnostic reproducibility of tumour budding in colorectal cancer: a multicentre,multinational study using virtual microscopy

Puppa G, Senore C, Sheahan K, Vieth M, Lugli A, Zlobec I, Pecori S, Wang L M, Langner C, Mitomi H, Nakamura T, Watanabe M, Ueno H, Chasle J, Conley S A, Herlin P, Lauwers G Y & Risio M
(2012) Histopathology  61, 562–575 Diagnostic reproducibility of tumour budding in colorectal cancer: a multicentre, multinational study using virtual microscopy Aims: Despite the established prognostic relevance of tumour budding in colorectal cancer, the reproducibility of the methods reported for its assessment has not yet been determined, limiting its use and reporting in routine pathology practice. Methods and results: A morphometric system within telepathology was devised to evaluate the reproducibility of the various methods published for the assessment of tumour budding in colorectal cancer. Five methods were selected to evaluate the diagnostic reproducibility among 10 investigators, using haematoxylin and eosin (H&E) and AE1‐3 cytokeratin‐immunostained, whole‐slide digital scans from 50 pT1–pT4 colorectal cancers. The overall interobserver agreement was fair for all methods, and increased to moderate for pT1 cancers. The intraobserver agreement was also fair for all methods and moderate for pT1 cancers. Agreement was dependent on the participants’ experience with tumour budding reporting and performance time. Cytokeratin immunohistochemistry detected a higher percentage of tumour budding‐positive cases with all methods compared to H&E‐stained slides, but did not influence agreement levels. Conclusions: An overall fair level of diagnostic agreement for tumour budding in colorectal cancer was demonstrated, which was significantly higher in early cancer and among experienced gastrointestinal pathologists. Cytokeratin immunostaining facilitated detection of budding cancer cells, but did not result in improved interobserver agreement.     

A Competent and Commercially Viable Process for the Synthesis of the Anti-Hypertensive Drug Olmesartan Medoxomil

Drug product purity and potency are of most significance in the regulatory market as we notice many recalled batches worldwide, particularly in the US and Japan. Olmesartan Medoxomil is an anti-hypertensive drug. The present invention relates to a process for the preparation of Olmesartan Medoxomil with 99.9% purity in an overall 62% yield. The synthesis includes three isolations and one purification with easy plant operations. This process describes the formation and control of each individual impurity in all stages. This process for Olmesartan Medoxomil and its intermediates is competent for industrial production in very short reaction time intervals with an appreciable yield and high purity.     

Incidence of stroke in the diabetic compared with the non‐diabetic population: A systematic review protocol

People with diabetes have a largely increased risk of stroke compared with people without diabetes. Exact data on incidence of stroke in people with and without diabetes are important for improvements in preventive diabetes care, avoidance of fatal outcomes and as a solid basis for health policy and the economy. However, published data are conflicting, underlining the necessity for this systematic review of population‐based studies on incidence, relative risks (RRs) and changes in stroke rates over time. The purpose of our review is to evaluate the incidence of stroke in the diabetic population and its differences with regard to sex, ethnicity, age and regions; to compare the incidence rate (IR) in the diabetic and non‐diabetic populations and to investigate time trends. We will perform a systematic literature search in MEDLINE, Embase and LILACS designed by an experienced information scientist. Two review authors will independently screen the abstracts and full texts of all references on the basis of inclusion criteria regarding types of study, types of population and the main outcome. Data extraction and assessment of risk of bias will be undertaken by two review authors working independently. We will assess IR or cumulative incidence (CumI) and RR of stroke comparing the diabetic and non‐diabetic populations. The attributable risk (AR = proportion of stroke among persons with diabetes that is attributable to diabetes) and the population attributable risk (PAR = proportion of stroke in the whole population that is attributable to diabetes) will be considered where available. In conclusion, this review will help to summarize the available evidence for incidence of stroke in the diabetic and nondiabetic population. The publication of this protocol will contribute to making the search strategy, methods, and assessment of reviews transparent and accessible for all involved professional groups.     

Systematic assessment of the prognostic impact of membranous CD44v6 protein expression in colorectal cancer

Aims:  To assess systematically the membranous expression of CD44v6 in colorectal cancer by immunohistochemistry to determine its prognostic impact, the differential expression between primary and metastatic tumours and expression differences between the tumour centre and invasive front.
Methods and results:  Immunohistochemistry was performed for CD44v6 on two tissue microarrays. The first included 1279 colorectal tumours with full clinicopathological data. The second consisted of 50 matched primary and metastatic tumours sampled from the tumour centre and the invasive margin. A scoring system was tested by multiple observers. Receiver–operating characteristic curve analysis was used for cut-off point determination. Loss of membranous CD44v6 was associated with pT stage ( P  = 0.016; sensitivity 85.8%, specificity 20.1%), lymph node metastasis ( P  = 0.015; sensitivity 52.8%, specificity 55%), an infiltrating tumour margin ( P  < 0.001; sensitivity 71.4%, specificity 40%) and adverse prognosis ( P  = 0.011; hazard ratio 0.79, 95% confidence interval 0.7, 0.9), but was not an independent prognostic factor on multivariable analysis. Loss of expression occurred at the invasive front in both primary and metastatic lesions ( P  < 0.001).
Conclusions:  This study outlines an approach to help standardize the immunohistochemical evaluation of CD44v6 and similar markers in colorectal cancer and highlights a significant role for loss of membranous CD44v6 expression in colorectal cancer progression and prognosis.     

BOB.1, CD79a and cyclin E are the most appropriate markers to discriminate classical Hodgkin’s lymphoma from primary mediastinal large B‐cell lymphoma

Hoeller S, Zihler D, Zlobec I, Obermann EC, Pileri SA, Dirnhofer S & Tzankov A
(2010) Histopathology 56, 217–228 BOB.1, CD79a and cyclin E are the most appropriate markers to discriminate classical Hodgkin’s lymphoma from primary mediastinal large B‐cell lymphoma Aims: To clarify which immunohistochemical markers could be helpful in distinguishing between classical Hodgkin’s lymphoma (cHL) and primary mediastinal B‐cell lymphoma (PMBCL) to more narrowly define ‘B‐cell lymphoma, unclassifiable, with features intermediate between diffuse large B‐cell lymphoma and cHL’. Methods and results: Two hundred and 83 cHLs and 51 PMBCLs were analysed on validated tissue microarray platforms with antibodies to BOB.1, CD15, CD20, CD23, CD30, CD79a, cyclin E, LMP‐1, MUM1p, p63 and Oct2. The marker cut‐off scores were calculated using receiver–operating characteristic curves. Markers with the highest positive predictive value for cHL were: CD15, cyclin E, LMP‐1 (all 100%), MUM1p (93%) and CD30 (83%). High sensitivity was achieved only by CD30 (92%) and cyclin E (79%). Nineteen percent of PMBCLs were also positive for CD30, which led to a lower specificity of CD30 as regards cHL (81%) compared with cyclin E (100%). The antibodies with the highest positive predictive value for PMBCL were: CD23 (98%), p63 (96%), BOB.1 (94%) and CD79a (90%), with high sensitivity for BOB.1 (100%), CD79a (89%) and p63 (82%). Conclusions: The use of at least three of the most accurate immunohistochemical markers, cyclin E, CD79a and BOB.1, may be helpful in the differential diagnosis of cHL and PMBCL.     

Prognostic significance of CD8+ T lymphocytes in breast cancer depends upon both oestrogen receptor status and histological grade

Baker K, Lachapelle J, Zlobec I, Bismar T A, Terracciano L & Foulkes W D (2011) Histopathology 58, 1107–1116 Prognostic significance of CD8 ⁺ T lymphocytes in breast cancer depends upon both oestrogen receptor status and histological grade Aims: Results of previous studies on the influence of tumour infiltrating lymphocytes on prognosis of women with breast cancer have been mixed. This study re‐evaluates the role of tumour‐infiltrating lymphocytes as a prognostic marker in women with breast cancer. Methods and results: Immunochemistry staining of CD8⁺ T cells was performed on a tissue microarray of 1953 breast carcinomas. When all tumours were considered, no association between the lymphocyte count and patient survival was found. In univariate analysis, there was a reduced disease‐specific survival for women with oestrogen receptor (ER)‐positive tumours with high intraepithelial lymphocyte count (P = 0.004). In those with ER‐negative tumours, the disease‐specific survival was improved when the intraepithelial, stromal and total lymphocyte counts were high, the total lymphocyte count also being an independent prognostic marker on multivariate analysis (P = 0.031). When stratified by histological grade, on univariate analysis, the previously observed inferior outcome in women with high lymphocyte count and ER‐positive tumours remained significant only if tumours were also of low grade, and the superior outcome in those with ER‐negative tumours remained significant if tumours were also of high grade. Conclusions: Our results raise the possibility of different immune–tumour interactions based on ER status and histological grade.     

EGFR-Mutationsanalyse beim nichtkleinzelligen Lungenkarzinom

Background

Some patients with non-small cell lung cancer (NSCLC) respond well to therapy with tyrosine kinase inhibitors (TKI). Somatic mutation of the epidermal growth factor receptor (EGFR) gene is an important predictive marker for TKI response.

Patients and methods

We performed EGFR mutation analysis in 307 NSCLC (exon 18-21). The data were analyzed for associations with clinical-pathological parameters.

Results

Relevant EGFR mutations were found in 25/307 NSCLC (8.1%; 178 biopsies and 129 cytologies). Most mutations were found in exon 19 (50%) followed by the L858R point mutation in exon 21 (12.5%). EGFR mutations were significantly more common in women than in men (16.8% vs. 2.7%; p<0.001) and in adenocarcinoma than in other carcinoma subtypes (11.4% vs. 3.8%; p=0.017). EGFR mutation was associated with TTF-1 positivity (p<0.041). Almost all (96%) mutated NSCLC were TTF-1 positive.

Conclusion

In Central Europe, the prevalence of relevant EGFR mutations in NSCLC is <10% of patients with NSCLC. EGFR mutations are more common in women and TTF-1 positive adenocarcinomas. Mutation analysis can be performed both from biopsies and cytologies.     

Epigenetic regulation of the human retinoblastoma tumor suppressor gene promoter by CTCF

Epigenetic misregulation is a more common feature in human cancer than previously anticipated. In the present investigation, we identified CCCTC-binding factor (CTCF), the multivalent 11-zinc-finger nuclear factor, as a regulator that favors a particular local chromatin conformation of the human retinoblastoma gene promoter. We show that its binding contributes to Rb gene promoter epigenetic stability. Ablation of the CTCF binding site from the human Rb gene promoter induced a rapid epigenetic silencing of reporter gene expression in an integrated genome context. CTCF DNA binding is methylation sensitive, and the methylated Rb-CTCF site is recognized by the Kaiso methyl-CpG-binding protein. This is the first evidence suggesting that CTCF protects the Rb gene promoter, a classic CpG island, against DNA methylation, and when such control region is abnormally methylated Kaiso, and probably its associated repressor complex, induce epigenetic silencing of the promoter. Our results identify CTCF as a novel epigenetic regulator of the human retinoblastoma gene promoter.