Analysis of potential response predictors to capecitabine/temozolomide in metastatic pancreatic neuroendocrine tumors

The capecitabine and temozolomide (CAPTEM) regimen is active in the treatment of metastatic pancreatic neuroendocrine tumors (pNETs), with response rates ranging from 30 to 70%. Small retrospective studies suggest that O(6)-methylguanine DNA methyltransferase (MGMT) deficiency predicts response to temozolomide. High tumor proliferative activity is also commonly perceived as a significant predictor of response to cytotoxic chemotherapy. It is unclear whether chromosomal instability (CIN), which correlates with alternative lengthening of telomeres (ALT), is a predictive factor. In this study, we evaluated 143 patients with advanced pNET who underwent treatment with CAPTEM for radiographic and biochemical response. MGMT expression (n=52), grade (n=128) and ALT activation (n=46) were investigated as potential predictive biomarkers. Treatment with CAPTEM was associated with an overall response rate (ORR) of 54% by RECIST 1.1. Response to CAPTEM was not influenced by MGMT expression, proliferative activity or ALT pathway activation. Based on these results, no biomarker-driven selection criteria for use of the CAPTEM regimen can be recommended at this time.

Striatal mRNA expression patterns underlying peak dose L-DOPA-induced dyskinesia in the 6-OHDA hemiparkinsonian rat

L-DOPA is the primary pharmacological treatment for relief of the motor symptoms of Parkinson's disease (PD). With prolonged treatment (⩾5 years) the majority of patients will develop abnormal involuntary movements as a result of L-DOPA treatment, known as L-DOPA-induced dyskinesia. Understanding the underlying mechanisms of dyskinesia is a crucial step toward developing treatments for this debilitating side effect. We used the 6-hydroxydopamine (6-OHDA) rat model of PD treated with a three-week dosing regimen of L-DOPA plus the dopa decarboxylase inhibitor benserazide (4 mg/kg and 7.5 mg/kgs.c., respectively) to induce dyskinesia in 50% of individuals. We then used RNA-seq to investigate the differences in mRNA expression in the striatum of dyskinetic animals, non-dyskinetic animals, and untreated parkinsonian controls at the peak of dyskinesia expression, 60 min after L-DOPA administration. Overall, 255 genes were differentially expressed; with significant differences in mRNA expression observed between all three groups. In dyskinetic animals 129 genes were more highly expressed and 14 less highly expressed when compared with non-dyskinetic and untreated parkinsonian controls. In L-DOPA treated animals 42 genes were more highly expressed and 95 less highly expressed when compared with untreated parkinsonian controls. Gene set cluster analysis revealed an increase in expression of genes associated with the cytoskeleton and phosphoproteins in dyskinetic animals compared with non-dyskinetic animals, which is consistent with recent studies documenting an increase in synapses in dyskinetic animals. These genes may be potential targets for drugs to ameliorate L-DOPA-induced dyskinesia or as an adjunct treatment to prevent their occurrence.

Evaluation of the risks of chemotherapy in dogs with thrombocytopenia

Thrombocytopenia is commonly encountered in veterinary oncology. Currently, there are no standard guidelines regarding the administration of chemotherapy to the patients with thrombocytopenia. This observational epidemiological cohort study aimed to determine whether thrombocytopenic dogs were at increased risk of gastrointestinal adverse effects (vomiting, diarrhoea, inappetence) or haemorrhage following administration of standard doses of chemotherapy. The adverse effects following 77 prospectively identified episodes of thrombocytopenia (platelet count, <200 000 µL^-1 ) were compared with the adverse effects experienced in a retrospective cohort (platelet count >200 000 µL^-1 ), and evaluated by statistical analysis. Overall, there was no statistically significant difference in the incidence of gastrointestinal adverse effects or haemorrhage between thrombocytopenic and control dogs. The control group of dogs with lymphoma were statistically more likely to experience vomiting as an adverse effect of chemotherapy (P = 0.028). The results presented here showed no evidence for an increased risk of gastrointestinal adverse effects or haemorrhage in thrombocytopenic dogs after receiving standard doses of chemotherapy.

Defining the genomic landscape of head and neck cancers through next-generation sequencing

Next-generation sequencing (NGS) has revolutionized the field of genomics and improved our understanding of cancer biology. Advances have been achieved by sequencing tumor DNA and using matched normal DNA to filter out germ line variants to identify cancer-specific changes. The identification of high incidences of activating mutations in head and neck squamous cell carcinoma (HNSCC) amenable to drug targeting has been made, with clear distinctions between the mutational profile of HPV-positive and HPV-negative tumors. This wealth of new understanding undoubtedly ameliorates our understanding of HNSCC cancer biology and elucidates clear targets for drug targeting which will guide future personalized medicine.

Abstract P6-05-05: Gene expression signatures of effector immune cell abundance are significantly associated with pathologic breast tumor response in the neoadjuvant setting

Background

Neoadjuvant chemotherapy for early breast cancer leads to significant clinical response rates of 70-90%, with only 10-20% complete pathologic responses (pCR). The biological and clinical factors that determine the degree of pCR are incompletely understood and most investigated are drug choice, proliferation index, intrinsic subtypes and host-therapy interactions. Mounting evidence indicates that the patient's immune system contributes to tumor regression and can be modulated by therapies. Investigations using immunohistochemical approaches confirmed that immune cell infiltrate on pre-treatment or post-treatment tumor biopsies are associated with greater frequency of pCR. The cell types most frequently observed with this association are effector tumor infiltrating lymphocytes (TILs) such as cytotoxic T cells, natural killer cells and B cells suggesting a strong link between infiltrating immune cell abundance and anti-tumor immunogenicity. More recently, we and others have shown that the relative abundance of TIL in breast cancer can be quantified by intratumoral transcript levels of coordinately expressed, immune cell-specific genes. Through expression microarray analysis, we recently discovered three separate immune gene signatures, or metagenes, that appear to reflect the relative abundance of distinct tumor-infiltrating leukocyte populations. These metagenes, referred as the B/P (B-cell/Plasma cell), T/NK (T-cell/Natural Killer cell) and M/D (Monocyte/Dendritic cell) immune metagenes, were significantly associated with the distant metastasis-free survival of patients with highly proliferative cancer of the Basal-like, HER2-Enriched and Luminal B subtypes, in particular.

Aim

Given the histopathological evidence that TIL abundance is predictive of neoadjuvant treatment efficacy, we evaluated the therapy-predictive potential of the prognostic immune metagenes. We hypothesized that the pre-chemotherapy immune gene signatures would be significantly predictive of tumor responses.

Methods

In a multi-institutional, meta-cohort analysis of 701 breast tumor patients receiving neoadjuvant chemotherapy, gene expression profiles of tumor biopsies were investigated to determine the relationships between immune metagenes, tumor proliferative capacity, and molecular breast tumor subtypes.

Results

We used multiple logistic regression to investigate the predictive value of the immune signatures. In a univariate analysis the B/P, T/NK and M/D immune metagenes were statistically significantly associated with excellent pathologic response as defined by residual cancer burden scores ((B/P (odds ratio (95% CI) 1.6 (1.3, 1.9), T/NK 1.6 (1.2, 2.0), M/D 1.7 (1.3, 2.1)). In multivariate analysis, B/P and M/D metagenes remained significant after adjustment for intrinsic subtype and proliferation (B/P 1.25 (1.01, 1.54), M/D 1.4 (1.03, 1.90).

Conclusions

Gene expression signatures of infiltrating immune cells carry both prognostic and therapy-predictive value. Furthermore, our work highlights a less described role for myeloid derived antigen presenting cells that could explain the variability of pathologic response to neoadjuvant chemotherapy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-05-05.

MRSA bacteraemia complicating amphotericin B treatment of cryptococcal meningitis

Intravenous amphotericin B is a key component of the antifungal therapy for cryptococcal meningitis recommended in South African and international guidelines. Unfortunately, its use is associated with significant toxicity including deterioration in renal function, electrolyte disturbance, anaemia and infusion reactions. Chemical phlebitis is common following administration via peripheral cannulae. This can be complicated by bacterial infection, resulting in localised cellulitis or bacterial sepsis. Here we describe two patients with cryptococcal meningitis who developed methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia during, or shortly after treatment with amphotericin B. These cases illustrate the dangers of line-related sepsis in hospitalised individuals and some of the difficulties encountered during treatment of this condition.

Age-related reference intervals for bone turnover markers from an Australian reference population

BACKGROUND

This study was performed to establish age-related serum reference intervals for procollagen type I N-propeptide (P1NP) and type I collagen C-telopeptide (CTx) in the Australian population.

METHODS

Fasting sera from 1143 males (mean age 60 years; range 20-97 years) and 1246 females (mean age 53 years; range 20-93 years) who participated in the Geelong Osteoporosis Study were analysed for CTx and P1NP using the automated Roche Modular Analytics E170 analyser.

RESULTS

Optimal age-related reference intervals were based on the central 90% of the distribution. The male CTx reference interval was divided into three age groups. For men aged 25 to 40 years, the interval was 170-600 ng/L; 40 to 60 years, the interval was 130-600 ng/L; and for men aged greater 60 years the interval was 100-600 ng/L. For P1NP the male reference interval was 15-80 μg/L for men aged between 25 to 70 years. In men greater than 70 years of age values were higher possibly due to increased bone turnover. High values are frequently seen for both CTx and P1NP in males aged younger than 25 years. This is probably due to bone growth that is not completely finalised. The female CTx reference interval was divided into four age groups. For women aged less than 30 years, the interval was 150-800 ng/L; 30-39 years, the interval was 100-700 ng/L; 40-49 years, the interval was 100-600 ng/L; and for women aged 50 years or more the interval was 100-700 ng/L. The female P1NP reference interval was divided into four age groups. For women aged less than 30 years, the interval was 25-90 μg/L; 30-39 years, the interval was 15-80 μg/L; 40-49 years, the interval was 15-60 μg/L; and for women aged 50-69 years the interval was 15-75 μg/L. In women greater than 70 years of age values were higher possibly due to increased bone turnover.

CONCLUSION

Values obtained from this large study provide sound age-related reference intervals for serum P1NP and CTx values in the Australian population.

Linking GABA(A) receptor subunits to alcohol-induced conditioned taste aversion and recovery from acute alcohol intoxication

GABA type A receptors (GABA(A)-R) are important for ethanol actions and it is of interest to link individual subunits with specific ethanol behaviors. We studied null mutant mice for six different GABA(A)-R subunits (α1, α2, α3, α4, α5 and δ). Only mice lacking the α2 subunit showed reduction of conditioned taste aversion (CTA) to ethanol. These results are in agreement with data from knock-in mice with mutation of the ethanol-sensitive site in the α2-subunit (Blednov et al., 2011). All together, they indicate that aversive property of ethanol is dependent on ethanol action on α2-containing GABA(A)-R. Deletion of the α2-subunit led to faster recovery whereas absence of the α3-subunit slowed recovery from ethanol-induced incoordination (rotarod). Deletion of the other four subunits did not affect this behavior. Similar changes in this behavior for the α2 and α3 null mutants were found for flurazepam motor incoordination. However, no differences in recovery were found in motor-incoordinating effects of an α1-selective modulator (zolpidem) or an α4-selective agonist (gaboxadol). Therefore, recovery of rotarod incoordination is under control of two GABA(A)-R subunits: α2 and α3. For motor activity, α3 null mice demonstrated higher activation by ethanol (1 g/kg) whereas both α2 (-/-) and α3 (-/Y) knockout mice were less sensitive to ethanol-induced reduction of motor activity (1.5 g/kg). These studies demonstrate that the effects of ethanol at GABAergic synapses containing α2 subunit are important for specific behavioral effects of ethanol which may be relevant to the genetic linkage of the α2 subunit with human alcoholism.

Analysis of the DISC1 translocation partner (11q14.3) in genetic risk of schizophrenia

The Disrupted-in-Schizophrenia 1 (DISC1) locus on human chromosome 1 was identified as a consequence of its involvement in a balanced translocation (1;11)(q42.1;q14.3) segregating with major psychiatric disorders in a Scottish family. Recently a comprehensive meta-analysis of genome-wide association scan data found no evidence that common variants of DISC1 (1q42.1) are associated with schizophrenia. Our aim was to test for association of variants in the 11q14.3 translocation region with schizophrenia. The 11q14.3 region was examined by meta-analysis of genome-wide scan data made available by the Genetic Association Information Network (GAIN) and other investigators (non-GAIN) through dbGap. P-values were adjusted for multiple testing using the false discovery rate (FDR) approach. There were no single-nucleotide polymorphisms (SNPs) significant (P < 0.05) after correction for multiple testing in the combined schizophrenia dataset. However, one SNP (rs2509382) was significantly associated in the male-only analysis with P(FDR)  = 0.024. Whilst the relevance of the (1;11)(q42.1;q14.3) translocation to psychiatric disorders is currently specific to the Scottish family, genetic material in the chromosome 11 region may contain risk variants for psychiatric disorders in the wider population. The association found in this region does warrant follow-up analysis in further sample sets.

Diabetic retinopathy at diagnosis of type 2 diabetes in Scotland

AIMS/HYPOTHESIS

The aim of this study was to examine the prevalence of and risk factors for diabetic retinopathy in people with newly diagnosed type 2 diabetes mellitus, using Scottish national data.

METHODS

We identified individuals diagnosed with type 2 diabetes mellitus in Scotland between January 2005 and May 2008 using data from the national diabetes database. We calculated the prevalence of retinopathy and ORs for risk factors associated with retinopathy at first screening.

RESULTS

Of the 51,526 people with newly diagnosed type 2 diabetes mellitus identified, 91.4% had been screened by 31 December 2010. The median time to first screening was 315 days (interquartile range [IQR] 111-607 days), but by 2008 the median was 83 days (IQR 51-135 days). The prevalence at first screening of any retinopathy was 19.3%, and for referable retinopathy it was 1.9%. For individuals screened after a year the prevalence of any retinopathy was 20.5% and referable retinopathy was 2.3%. Any retinopathy at screening was associated with male sex (OR 1.19, 95% CI 1.14, 1.25), HbA(1c) (OR 1.07, 95% CI 1.06, 1.08 per 1% [11 mmol/mol] increase), systolic BP (OR 1.06, 95% CI 1.05, 1.08 per 10 mmHg increase), time to screening (OR for screening >1 year post diagnosis = 1.12, 95% CI 1.07, 1.17) and obesity (OR 0.87, 95% CI 0.82, 0.93) in multivariate analysis.

CONCLUSIONS/INTERPRETATION

The prevalence of retinopathy at first screening is lower than in previous UK studies, consistent with earlier diagnosis of diabetes. Most newly diagnosed type 2 diabetic patients in Scotland are screened within an acceptable interval and the prevalence of referable disease is low, even in those with delayed screening.

External quality assurance for image grading in the Scottish Diabetic Retinopathy Screening Programme

AIMS

To develop and evaluate an image grading external quality assurance system for the Scottish Diabetic Retinopathy Screening Programme.

METHOD

A web-based image grading system was developed which closely matches the current Scottish national screening software. Two rounds of external quality assurance were run in autumn 2008 and spring 2010, each time using the same 100 images. Graders were compared with a consensus standard derived from the top-level graders' results. After the first round, the centre lead clinicians and top-level graders reviewed the results and drew up guidance notes for the second round.

RESULTS

Grader sensitivities ranged from 60.0 to 100% (median 92.5%) in 2008, and from 62.5 to 100% (median 92.5%) in 2010. Specificities ranged from 34.0 to 98.0% (median 86%) in 2008, and 54.0 to 100% (median 88%) in 2010. There was no difference in sensitivity between grader levels, but first-level graders had a significantly lower specificity than level-two and level-three graders. In 2008, one centre had a lower sensitivity but higher specificity than the majority of centres. Following the feedback from the first round, overall agreement improved in 2010 and there were no longer any significant differences between centres.

CONCLUSIONS

A useful educational tool has been developed for image grading external quality assurance.

A 20-year retrospective study of tonsil cancer incidence and survival trends in South East England: 1987-2006

BACKGROUND

There has been an increasing incidence of tonsil cancer worldwide. Documenting these changes is crucial to cancer prevention and control measures, resource allocation and understanding disease aetiology.

OBJECTIVE

To analyse the changing epidemiology of tonsil cancer in South East England over a 20-year period between 1987 and 2006.

DESIGN

A retrospective, quantitative study using secondary anonymised data obtained from the Thames Cancer Registry, London. Data were analysed using spss v.17 and survival analyses with Kaplan-Meier and Cox regression.

SETTING

This study was conducted in South East of England comprising London, Kent, Surrey and Sussex counties with an average population of 12 million. This population increased from 10.7 to 11.8 million (a 10% increase) between 1987 and 2006.

PARTICIPANTS

All patients with tonsil cancer in South East England registered with the Thames Cancer Registry (ICD-10 code C09) between 1987 and 2006. A total of 1794 patients' data were analysed. Ethical Considerations: Ethical approval was granted by the Kent Research Ethics Committee.

MAIN OUTCOME MEASURES

Data were analysed for demographic trends including gender, age at diagnosis, yearly incidence and survival.

RESULTS

Tonsil cancer incidence has increased significantly from 0.60 to 1.45 per 100,000 in the 20 years (P < 0.001). This increase is mainly amongst men and age groups 40-59 years with a significant reduction in age at diagnosis by 2 years from 61.6 years in the first decade to 59.6 years in the second decade (P < 0.001). Survival was worse in men, older age groups and in the presence of synchronous tumours (P < 0.001). There has been a statistically significant increase in median survival times from tonsil cancer by about 3 years from 2.7 years in the first decade to 5.7 years in the second decade of this study (P < 0.001).

CONCLUSIONS

Tonsil cancer incidence has increased in the 20 years of this study in South East England, especially amongst men and age groups 40-59 years. There has also been significant reduction in the mean age at diagnosis and an increase in median survival times for tonsil cancer. Further studies are needed to explain these trends.

P5-14-07: Novel Interactions between Immunity and Proliferation in Breast Cancer Prognosis

Highly proliferative breast tumors are phenotypically and clinically heterogeneous and exhibit a significant metastatic tendency. However, not all highly proliferative breast cancers will progress to distant metastasis, suggesting that other factors may play a role in limiting their clinical progression. With an interest in identifying genes that predict metastatic capacity of breast cancers in a proliferation-dependent context, we recently compiled a database of ∼2,000 tumor expression profiles using microarray data from multiple large breast cancer cohorts. We randomized the dataset into training and testing sets to allow discovery and validation of novel gene-survival (ie, distant metastasis-free survival; DMFS) associations. We employed Cox regression analysis to identify genes with statistically significant associations with DMFS. Then, we hierarchically clustered the expression patterns of the significant genes to identify gene clusters lacking correlation with proliferation genes. A large cluster of genes with known functions in innate and adaptive immunity emerged. Cross referencing these genes to a published microarray dataset of pan-leukocyte expression profiles revealed cell type-specific structure within the immunity cluster, likely reflective of distinct populations of tumor-infiltrating immune cells. Specifically, 3 immune gene subclusters identified within the tumors showed predominant expression in B-cells, T-cells and natural killer (T/NK) cells, or monoctytes and dendritic (M/D) cells. To evaluate the prognostic relevance of these immune gene clusters, we averaged the gene expression measurements within each cluster to generate “metagenes” that could be used to divide breast cancer cases into population tertiles based on the low, intermediate and high expression of the immune genes. The same was done for a large cluster of proliferation genes known to reflect the proliferative capacity of breast cancer cells. Strikingly, we found that that prognostic power of the B-cell, T/NK and M/D metagenes was not consistent among the proliferation tertiles, but rather, was exclusively statistically significant in the highest proliferation tertile, enriched for basal-like, luminal B and HER2+-like tumors. In these tumors, all 3 immune metagenes stratified cases into low, intermediate and high risk of recurrence with high statistical significance (p&lt;0.0001), wherein the highest expression tertile of the immune metagenes corresponded to reduced risk of metastatic recurrence (at 5 and 10 years), consistent with a long-term anti-metastatic immune response. Comparative analysis of the B and T/NK metagenes revealed a highly significant prognostic interaction between the two, whereby the low expression tertile of either the B-cell or T/NK metagene portends a poor prognosis that is not overcome by a high expression tertile of the other. Our results suggest that cell type-specific immune signatures in breast cancer can predict survival in highly proliferative subtypes of breast cancer, with potential to spare some patients from aggressive adjuvant treatment while identifying others who will require more than standard of care. Furthermore, our results provide novel insight into the important roles of T and B cell-mediated immunity in breast cancer progression.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-14-07.

The Effect of Increasing Two-Week Wait Referrals for Head and Neck Cancer in East Kent

In 1998 the UK government published its white paper The New NHS: Modern and Dependable, in which it first suggested that patients being referred with a suspicion of cancer should have a maximum wait of two weeks to see a specialist. The rationale for this was that outcomes for late-stage disease are significantly worse when compared with outcomes for early-stage disease (Table 1). It was assumed that reducing the wait to see a specialist would reduce the stage of disease at presentation.

Nursing sisters' satisfaction with the pharmacy service — a survey

A questionnaire was sent to all nursing sisters in Hammersmith and Queen Charlotte's special health authority, a provider of specialist hospital services in London. They were asked for their overall impression of the pharmacy service and staff, for their opinions of specific services and for suggestions for improving the service. Eighty-six per cent of respondents thought the service was good, very good or excellent and 92 per cent thought the service was either the same or better than that of other hospitals in which they had worked.

Just under half the suggestions received were for service improvements related to supply of drugs stocked on the ward. The other main areas commented on were drug delivery, discharge medication and the pharmacy on-call service. The survey provided useful information about the pharmacy service and has enabled the department to implement some of the changes suggested as well as look at the feasibility of other improvements. It is intended to repeat this survey annually.