Selenium and Vitamin E for Prevention of Non-Muscle-Invasive Bladder Cancer Recurrence and Progression: A Randomized Clinical Trial

Importance

Selenium and vitamin E have been identified as promising agents for the chemoprevention of recurrence and progression of non-muscle-invasive bladder cancer.

Objective

To determine whether selenium and/or vitamin E may prevent disease recurrence in patients with newly diagnosed NMIBC.

Design, Setting, and Participants

This multicenter, prospective, double-blinded, placebo-controlled, 2 × 2 factorial randomized clinical trial included patients with newly diagnosed NMIBC recruited from 10 secondary or tertiary care hospitals in the UK. A total of 755 patients were screened for inclusion; 484 did not meet the inclusion criteria, and 1 declined to participate. A total of 270 patients were randomly assigned to 4 groups (selenium plus placebo, vitamin E plus placebo, selenium plus vitamin E, and placebo plus placebo) in a double-blind fashion between July 17, 2007, and October 10, 2011. Eligibility included initial diagnosis of NMIBC (stages Ta, T1, or Tis); randomization within 12 months of first transurethral resection was required.

Interventions

Oral selenium (200 μg/d of high-selenium yeast) and matched vitamin E placebo, vitamin E (200 IU/d of d-alfa-tocopherol) and matched selenium placebo, selenium and vitamin E, or placebo and placebo.

Main Outcome and Measures

Recurrence-free interval (RFI) on an intention-to-treat basis (analyses completed on November 28, 2022).

Results

The study randomized 270 patients (mean [SD] age, 68.9 [10.4] years; median [IQR] age, 69 [63-77] years; 202 male [75%]), with 65 receiving selenium and vitamin E placebo, 71 receiving vitamin E and selenium placebo, 69 receiving selenium and vitamin E, and 65 receiving both placebos. Median overall follow-up was 5.5 years (IQR, 5.1-6.1 years); 228 patients (84%) were followed up for more than 5 years. Median treatment duration was 1.5 years (IQR, 0.9-2.5 years). The study was halted because of slow accrual. For selenium (n = 134) vs no selenium (n = 136), there was no difference in RFI (hazard ratio, 0.92; 95% CI, 0.65-1.31; P = .65). For vitamin E (n = 140) vs no vitamin E (n = 130), there was a statistically significant detriment to RFI (hazard ratio, 1.46; 95% CI, 1.02-2.09; P = .04). No significant differences were observed for progression-free interval or overall survival time with either supplement. Results were unchanged after Cox proportional hazards regression modeling to adjust for known prognostic factors. In total, 1957 adverse events were reported; 85 were serious adverse events, and all were considered unrelated to trial treatment.

Conclusions and Relevance

In this randomized clinical trial of selenium and vitamin E, selenium supplementation did not reduce the risk of recurrence in patients with NMIBC, but vitamin E supplementation was associated with an increased risk of recurrence. Neither selenium nor vitamin E influenced progression or overall survival. Vitamin E supplementation may be harmful to patients with NMIBC, and elucidation of the underlying biology is required.

Trial Registration

isrctn.org Identifier: ISRCTN13889738.

Health-related quality of life around the time of diagnosis in patients with bladder cancer

OBJECTIVES

To quantify the health-related quality of life (HRQoL) of patients with bladder cancer around the time of diagnosis and to test the hypotheses of a two-factor model for the HRQoL questionnaire QLQ-C30.

METHODS

From participants in the Bladder Cancer Prognoses Programme, a multicentre cohort study, sociodemographic data were collected using semi-structured face-to-face interviews. Answers to the QLQ-C30 were transformed into a scale from 0 to 100. HRQoL data were analysed in multivariate analyses. The hypothesized two-factor (Physical and Mental Health) domain structure of the QLQ-C30 was also tested with confirmatory factor analyses (CFA).

RESULTS

A total of 1160 participants (78%) completed the questionnaire after initial visual diagnosis and before pathological confirmation. Despite non-muscle-invasive bladder cancer (NMIBC) being associated with a higher HRQoL than carcinoma invading bladder muscle, only the domain Role Functioning was clinically significantly better in patients with NMIBC. Age, gender, bladder cancer stage and comorbidity all had a significant influence on QLQ-C30 scores. The CFA showed an overall good fit of the hypothesized two-factor model.

CONCLUSION

This study identified a baseline reference value for HRQoL for patients with bladder cancer, which allows better evaluation of any changes in HRQoL as disease progresses or after treatment. In addition, a two-factor (Physical and Mental Health) model was developed for the QLQ-C30.

Patients choose certainty over burden in bladder cancer surveillance

BACKGROUND

Due to the high risk of recurrence of non-muscle invasive bladder cancer, all patients undergo regular cystoscopic surveillance for early detection. As cystoscopy is invasive, costly and increases the burden of the disease considerably, there is significant ongoing research and development into non-invasive urinary biomarker substitutes. This study aims to assess the level of sensitivity required before patients accept a new urinary biomarker.

METHODS

We studied the preferences for a hypothetical diagnostic urinary biomarker and compared this to usual care (cystoscopy) at different levels of sensitivity among 437 patients with bladder cancer (354 men and 83 women) from the UK Bladder Cancer Prognosis Programme. A standard gamble approach was used to estimate the minimally acceptable sensitivity (MAS) of the new biomarker. Additionally, non-parametric statistical analyses were performed to investigate the association between surveillance preference and various patient characteristics.

RESULTS

Almost half of patients (183, 43%) would not replace cystoscopy with a urinary biomarker unless it was 100% sensitive. The median MAS was 99.9999%, and nearly 85% of patients demanded a sensitivity of at least 99% before preferring a urinary biomarker test over cystoscopy. These results were consistent across all patient characteristics and demographic categories.

CONCLUSIONS

Our results indicate that patients demand urinary biomarkers as sensitive as cystoscopy before they would be willing to forego cystoscopy for bladder cancer surveillance.

Radiofrequency-induced Thermo-chemotherapy Effect Versus a Second Course of Bacillus Calmette-Guérin or Institutional Standard in Patients with Recurrence of Non-muscle-invasive Bladder Cancer Following Induction or Maintenance Bacillus Calmette-Guérin Therapy (HYMN): A Phase III, Open-label, Randomised Controlled Trial

BACKGROUND

There is no effective intravesical second-line therapy for non-muscle-invasive bladder cancer (NMIBC) when bacillus Calmette-Guérin (BCG) fails.

OBJECTIVE

To compare disease-free survival time (DFS) between radiofrequency-induced thermo-chemotherapy effect (RITE) and institutional standard second-line therapy (control) in NMIBC patients with recurrence following induction/maintenance BCG.

DESIGN, SETTINGS, AND PARTICIPANTS

Open-label, phase III randomised controlled trial accrued across 14 centres between May 2010 and July 2013 (HYMN [ClinicalTrials.gov: NCT01094964]).

INTERVENTION

Patients were randomly assigned (1:1) to RITE (60min, 40mg mitomycin-C, 42±2°C) or control following stratification for carcinoma in situ (CIS) status (present/absent), therapy history (failure of previous induction/maintenance BCG), and treatment centre.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Primary outcome measures were DFS and complete response (CR) at 3 mo for the CIS at randomisation subgroup. Analysis was based on intention-to-treat.

RESULTS AND LIMITATIONS

A total of 104 patients were randomised (48 RITE: 56 control). Median follow-up for the 31 patients without a DFS event was 36 mo. There was no significant difference in DFS between treatment arms (hazard ratio [HR] 1.33, 95% confidence interval [CI] 0.84-2.10, p=0.23) or in 3-mo CR rate in CIS patients (n=71; RITE: 30% vs control: 47%, p=0.15). There was no significant difference in DFS between treatment arms in non-CIS patients (n=33; RITE: 53% vs control: 24% at 24 mo, HR 0.50, 95% CI 0.22-1.17, p=0.11). DFS was significantly lower in RITE than in control in CIS with/without papillary patients (n=71; HR 2.06, 95% CI 1.17-3.62, p=0.01; treatment-subgroup interaction p=0.007). Disease progression was observed in four patients in each treatment arm. Adverse events and health-related quality of life between treatment arms were comparable.

CONCLUSIONS

DFS was similar between RITE and control. RITE may be a second-line therapy for non-CIS recurrence following BCG failure; however, confirmatory trials are needed. RITE patients with CIS with/without papillary had lower DFS than control. HYMN highlights the importance of the control arm when evaluating novel therapies.

PATIENT SUMMARY

This study did not show a difference in bladder cancer outcomes between microwave-heated chemotherapy and standard of care treatment. Papillary bladder lesions may benefit from microwave-heated chemotherapy treatment; however, more research is needed. Both treatments are similarly well tolerated.

Dose Transition Pathways: The Missing Link Between Complex Dose-Finding Designs and Simple Decision-Making

The ever-increasing pace of development of novel therapies mandates efficient methodologies for assessment of their tolerability and activity. Evidence increasingly support the merits of model-based dose-finding designs in identifying the recommended phase II dose compared with conventional rule-based designs such as the 3 + 3 but despite this, their use remains limited. Here, we propose a useful tool, dose transition pathways (DTP), which helps overcome several commonly faced practical and methodologic challenges in the implementation of model-based designs. DTP projects in advance the doses recommended by a model-based design for subsequent patients (stay, escalate, de-escalate, or stop early), using all the accumulated information. After specifying a model with favorable statistical properties, we utilize the DTP to fine-tune the model to tailor it to the trial's specific requirements that reflect important clinical judgments. In particular, it can help to determine how stringent the stopping rules should be if the investigated therapy is too toxic. Its use to design and implement a modified continual reassessment method is illustrated in an acute myeloid leukemia trial. DTP removes the fears of model-based designs as unknown, complex systems and can serve as a handbook, guiding decision-making for each dose update. In the illustrated trial, the seamless, clear transition for each dose recommendation aided the investigators' understanding of the design and facilitated decision-making to enable finer calibration of a tailored model. We advocate the use of the DTP as an integral procedure in the co-development and successful implementation of practical model-based designs by statisticians and investigators. Clin Cancer Res; 23(24); 7440-7. ©2017 AACR.

Effect of topical imiquimod as primary treatment for lentigo maligna: the LIMIT-1 study

BACKGROUND

Topical imiquimod is sometimes used for lentigo maligna (LM) in situ melanoma instead of surgery, but frequency of cure is uncertain. Pathological complete regression (pCR) is a logical surrogate marker for cure after imiquimod, although residual LM and atypical melanocytic hyperplasia may not be reliably distinguished. A trial comparing imiquimod vs. surgery might be justified by a high imiquimod pCR rate.

OBJECTIVES

Primary: to estimate the pCR rate for LM following imiquimod. Secondary: to assess the accuracy of prediction of pCR, using clinical complete regression (cCR) plus negative post-treatment biopsies, tolerability, resource use, patients' preferences and induced melanoma immunity.

METHODS

This was a single-arm phase II trial of 60 imiquimod applications over 12 weeks for LM then radical resection. A pCR rate ≥ 25 out of 33 would reliably discriminate between pCR rates < 60% and ≥ 85%. Clinical response was assessed and biopsies taken after imiquimod. Patients recorded adverse events in diaries. Patient preference was measured after surgery using a standard gamble tool.

RESULTS

The pCR rate was 10 of 27 (37%, 95% confidence interval 19-58%). The rate of cCR plus negative biopsies was 12 of 28, of whom seven of 11 had pCR on subsequent surgery. The median dose intensity was 86·7%. Of the 16 surveyed patients, eight preferred primary imiquimod over surgery if the cure rate for imiquimod was 80%, and four of 16 if it was ≤ 40%.

CONCLUSIONS

The pCR rate was insufficient to justify phase III investigation of imiquimod vs.

SURGERY

Clinical complete response and negative targeted biopsies left uncertainty regarding pathological clearance. Some patients would trade less aggressive treatment of LM against efficacy.

Cost-effectiveness of zoledronic acid and strontium-89 as bone protecting treatments in addition to chemotherapy in patients with metastatic castrate-refractory prostate cancer: results from the TRAPEZE trial (ISRCTN 12808747)

OBJECTIVE

To evaluate the cost-effectiveness of adding zoledronic acid or strontium-89 to standard docetaxel chemotherapy for patients with castrate-refractory prostate cancer (CRPC).

PATIENTS AND METHODS

Data on resource use and quality of life for 707 patients collected prospectively in the TRAPEZE 2 × 2 factorial randomised trial (ISRCTN 12808747) were used to assess the cost-effectiveness of i) zoledronic acid versus no zoledronic acid (ZA vs. no ZA), and ii) strontium-89 versus no strontium-89 (Sr89 vs. no Sr89). Costs were estimated from the perspective of the National Health Service in the UK and included expenditures for trial treatments, concomitant medications, and use of related hospital and primary care services. Quality-adjusted life-years (QALYs) were calculated according to patients' responses to the generic EuroQol EQ-5D-3L instrument, which evaluates health status. Results are expressed as incremental cost-effectiveness ratios (ICERs) and cost-effectiveness acceptability curves.

RESULTS

The per-patient cost for ZA was £12 667, £251 higher than the equivalent cost in the no ZA group. Patients in the ZA group had on average 0.03 QALYs more than their counterparts in no ZA group. The ICER for this comparison was £8 005. Sr89 was associated with a cost of £13 230, £1365 higher than no Sr89, and a gain of 0.08 QALYs compared to no Sr89. The ICER for Sr89 was £16 884. The probabilities of ZA and Sr89 being cost-effective were 0.64 and 0.60, respectively.

CONCLUSIONS

The addition of bone-targeting treatments to standard chemotherapy led to a small improvement in QALYs for a modest increase in cost (or cost-savings). ZA and Sr89 resulted in ICERs below conventional willingness-to-pay per QALY thresholds, suggesting that their addition to chemotherapy may represent a cost-effective use of resources.

The National Lung Matrix Trial: translating the biology of stratification in advanced non-small-cell lung cancer

BACKGROUND

The management of NSCLC has been transformed by stratified medicine. The National Lung Matrix Trial (NLMT) is a UK-wide study exploring the activity of rationally selected biomarker/targeted therapy combinations.

PATIENTS AND METHODS

The Cancer Research UK (CRUK) Stratified Medicine Programme 2 is undertaking the large volume national molecular pre-screening which integrates with the NLMT. At study initiation, there are eight drugs being used to target 18 molecular cohorts. The aim is to determine whether there is sufficient signal of activity in any drug-biomarker combination to warrant further investigation. A Bayesian adaptive design that gives a more realistic approach to decision making and flexibility to make conclusions without fixing the sample size was chosen. The screening platform is an adaptable 28-gene Nextera next-generation sequencing platform designed by Illumina, covering the range of molecular abnormalities being targeted. The adaptive design allows new biomarker-drug combination cohorts to be incorporated by substantial amendment. The pre-clinical justification for each biomarker-drug combination has been rigorously assessed creating molecular exclusion rules and a trumping strategy in patients harbouring concomitant actionable genetic abnormalities. Discrete routes of pathway activation or inactivation determined by cancer genome aberrations are treated as separate cohorts. Key translational analyses include the deep genomic analysis of pre- and post-treatment biopsies, the establishment of patient-derived xenograft models and longitudinal ctDNA collection, in order to define predictive biomarkers, mechanisms of resistance and early markers of response and relapse.

CONCLUSION

The SMP2 platform will provide large scale genetic screening to inform entry into the NLMT, a trial explicitly aimed at discovering novel actionable cohorts in NSCLC.

CLINICAL TRIAL ISRCTN

38344105.

A Practical Application of Value of Information and Prospective Payback of Research to Prioritize Evaluative Research

BACKGROUND AND OBJECTIVES

Efforts to ensure that funded research represents "value for money" have led to increasing calls for the use of analytic methods in research prioritization. A number of analytic approaches have been proposed to assist research funding decisions, the most prominent of which are value of information (VOI) and prospective payback of research (PPoR). Despite the increasing interest in the topic, there are insufficient VOI and PPoR applications on the same case study to contrast their methods and compare their outcomes. We undertook VOI and PPoR analyses to determine the value of conducting 2 proposed research programs. The application served as a vehicle for identifying differences and similarities between the methods, provided insight into the assumptions and practical requirements of undertaking prospective analyses for research prioritization, and highlighted areas for future research.

METHODS

VOI and PPoR were applied to case studies representing proposals for clinical trials in advanced non-small-cell lung cancer and prostate cancer. Decision models were built to synthesize the evidence available prior to the funding decision. VOI (expected value of perfect and sample information) and PPoR (PATHS model) analyses were undertaken using the developed models.

RESULTS AND CONCLUSIONS

VOI and PPoR results agreed in direction, suggesting that the proposed trials would be cost-effective investments. However, results differed in magnitude, largely due to the way each method conceptualizes the possible outcomes of further research and the implementation of research results in practice. Compared with VOI, PPoR is less complex but requires more assumptions. Although the approaches are not free from limitations, they can provide useful input for research funding decisions.

Meta-analysis of randomized phase II trials to inform subsequent phase III decisions

BACKGROUND

If multiple Phase II randomized trials exist then meta-analysis is favorable to increase statistical power and summarize the existing evidence about an intervention's effect in order to help inform Phase III decisions. We consider some statistical issues for meta-analysis of Phase II trials for this purpose, as motivated by a real example involving nine Phase II trials of bolus thrombolytic therapy in acute myocardial infarction with binary outcomes.

METHODS

We propose that a Bayesian random effects logistic regression model is most suitable as it models the binomial distribution of the data, helps avoid continuity corrections, accounts for between-trial heterogeneity, and incorporates parameter uncertainty when making inferences. The model also allows predictions that inform Phase III decisions, and we show how to derive: (i) the probability that the intervention will be truly beneficial in a new trial, and (ii) the probability that, in a new trial with a given sample size, the 95% credible interval for the odds ratio will be entirely in favor of the intervention. As Phase II trials are potentially optimistic due to bias in design and reporting, we also discuss how skeptical prior distributions can reduce this optimism to make more realistic predictions.

RESULTS

In the example, the model identifies heterogeneity in intervention effect missed by an I-squared of 0%. Prediction intervals accounting for this heterogeneity are shown to support subsequent Phase III trials. The probability of success in Phase III trials increases as the sample size increases, up to 0.82 for intracranial hemorrhage and 0.79 for reinfarction outcomes.

CONCLUSIONS

The choice of meta-analysis methods can influence the decision about whether a trial should proceed to Phase III and thus need to be clearly documented and investigated whenever a Phase II meta-analysis is performed.

Smoking is associated with lower age, higher grade, higher stage, and larger size of malignant bladder tumors at diagnosis

Smoking is a strong risk factor of bladder cancer (BC), but it is currently unclear whether smoking is also associated with severity of BC at diagnosis. We performed a large hospital-based case-comparison study, examining the relation between smoking and clinical characteristics of BC at diagnosis. A total of 1,544 cases from participating hospitals in the West Midlands were recruited between 19 December 2005 and 21 April 2011. Eligible cases were adult BC patients without a previous history of this disease. At time of diagnosis, semi-structured face-to-face interviews were conducted by trained research nurses to collect smoking information. Clinical characteristics were obtained from medical records. Linear mixed models were performed to calculate predicted means in clinical outcomes for a variety of smoking behaviors. A p < 0.05 was considered statistically significant. After adjustment for age and gender, current smokers were on average 4.0 years younger at diagnosis (95% CI: -5.9 to -2.0), had larger tumors (mean difference: 0.48 cm, 95% CI: 0.04-0.91), a higher T stage (mean difference: 0.25, 95% CI: 0.08-0.41), and a borderline significantly higher grade than never smokers (mean difference: 0.15, 95% CI: 0.00-0.30). Our results suggest that smoking could be associated with a more malignant phenotype of BC at diagnosis. More research is needed on the relation between smoking and prognosis, but our results could strengthen the message about the potential risks of smoking to these patients.

Sample size calculations for designing clinical proteomic profiling studies using mass spectrometry

In cancer clinical proteomics, MALDI and SELDI profiling are used to search for biomarkers of potentially curable early-stage disease. A given number of samples must be analysed in order to detect clinically relevant differences between cancers and controls, with adequate statistical power. From clinical proteomic profiling studies, expression data for each peak (protein or peptide) from two or more clinically defined groups of subjects are typically available. Typically, both exposure and confounder information on each subject are also available, and usually the samples are not from randomized subjects. Moreover, the data is usually available in replicate. At the design stage, however, covariates are not typically available and are often ignored in sample size calculations. This leads to the use of insufficient numbers of samples and reduced power when there are imbalances in the numbers of subjects between different phenotypic groups. A method is proposed for accommodating information on covariates, data imbalances and design-characteristics, such as the technical replication and the observational nature of these studies, in sample size calculations. It assumes knowledge of a joint distribution for the protein expression values and the covariates. When discretized covariates are considered, the effect of the covariates enters the calculations as a function of the proportions of subjects with specific attributes. This makes it relatively straightforward (even when pilot data on subject covariates is unavailable) to specify and to adjust for the effect of the expected heterogeneities. The new method suggests certain experimental designs which lead to the use of a smaller number of samples when planning a study. Analysis of data from the proteomic profiling of colorectal cancer reveals that fewer samples are needed when a study is balanced than when it is unbalanced, and when the IMAC30 chip-type is used. The method is implemented in the clippda package and is available in R at: http://www.bioconductor.org/help/bioc-views/release/bioc/html/clippda.html.

Assessment of high-throughput high-resolution MALDI-TOF-MS of urinary peptides for the detection of muscle-invasive bladder cancer

PURPOSE

There is a need for better biomarkers to both detect bladder cancer and distinguish muscle-invasive (stage T2+) from non-invasive (stage Ta/T1) disease. We assess whether MALDI-TOF-MS of the urine peptidome can achieve this.

EXPERIMENTAL DESIGN

We analysed urine from 751 patients with bladder cancer and 127 patients without bladder cancer. Endogenous peptide profiling was performed using a Bruker Ultraflextreme MALDI-TOF-MS.

RESULTS

Significant differences were seen between the spectra of urine from patients with and without T2+ disease. Albumin, total protein and haematuria were also elevated in T2+ patients. Haematuria was detected in 39% of patients with Ta/T1 disease and in 77% of patients with T2+ disease. Class prediction models based on MALDI data produced areas under receiver-operator characteristic curves of up to 0.76 but did not significantly outperform a model based on total protein alone. Many peptides significantly associated with invasive disease are fragments of abundant blood proteins and are also associated with haematuria.

CONCLUSIONS AND CLINICAL RELEVANCE

Microscopic haematuria is strongly associated with invasive disease; even traces of blood/plasma strongly influence the urinary peptidome. This needs to be taken into consideration when using 'omic' methods to search for urinary biomarkers as blood proteins may give false-positive results.

Estrogen receptor and progesterone receptor as predictive biomarkers of response to endocrine therapy: a prospectively powered pathology study in the Tamoxifen and Exemestane Adjuvant Multinational trial

PURPOSE

The Tamoxifen and Exemestane Adjuvant Multinational (TEAM) trial included a prospectively planned pathology substudy testing the predictive value of progesterone receptor (PgR) expression for outcome of estrogen receptor-positive (ER-positive) early breast cancer treated with exemestane versus tamoxifen.

PATIENTS AND METHODS

Pathology blocks from 4,781 TEAM patients randomly assigned to exemestane versus tamoxifen followed by exemestane for 5 years of total therapy were collected centrally, and tissue microarrays were constructed from samples from 4,598 patients. Quantitative analysis of hormone receptors (ER and PgR) was performed by using image analysis and immunohistochemistry, and the results were linked to outcome data from the main TEAM trial and analyzed relative to disease-free survival and treatment.

RESULTS

Of 4,325 eligible ER-positive patients, 23% were PgR-poor (Allred < 4) and 77% were PgR- rich (Allred ≥ 5). No treatment-by-marker effect for PgR was observed for exemestane versus tamoxifen (PgR-rich hazard ratio [HR], 0.83; 95% CI, 0.65 to 1.05; PgR-poor HR, 0.85; 95% CI, 0.61 to 1.19; P = .88 for interaction). Both PgR and ER expression were associated with patient prognosis in univariate (PgR HR, 0.53; 95% CI, 0.43 to 0.65; P < .001; ER HR, 0.66; 95% CI, 0.51 to 0.86; P = .002), and multivariate analyses (P < .001 and P = .001, respectively). A trend toward a treatment-by-marker effect for ER-rich patients was observed.

CONCLUSION

Preferential exemestane versus tamoxifen treatment benefit was not predicted by PgR expression; conversely, patients with ER-rich tumors may derive additional benefit from exemestane. Quantitative analysis of ER and PgR expression provides highly significant information on risk of early relapse (within 1 to 3 years) during treatment.

Phase I/II trial of a dendritic cell vaccine transfected with DNA encoding melan A and gp100 for patients with metastatic melanoma

This trial tested a dendritic cell (DC) therapeutic cancer vaccine in which antigen is loaded using a novel non-viral transfection method enabling the uptake of plasmid DNA condensed with a cationic peptide. Proof of principle required the demonstration of diverse T lymphocyte responses following vaccination, including multiple reactivities restricted through both major histocompatibility complex (MHC) class I and II. Patients with advanced melanoma were offered four cycles of vaccination with autologous DC expressing melan A and gp100. Disease response was measured using Response Evaluation Criteria in Solid Tumours. Circulating MHC class I- and II-restricted responses were measured against peptide and whole antigen targets using interferon-γ ELIspot and enzyme-linked immunosorbent assay assays, respectively. Responses were analyzed across the trial population and presented descriptively for some individuals. Twenty-five patients received at least one cycle. Vaccination was well tolerated. Three patients had reduction in disease volume. Across the trial population, vaccination resulted in an expansion of effector responses to both antigens, to the human leukocyte antigen A2-restricted modified epitope, melan A ELAGIGILTV, and to a panel of MHC class I- and II-restricted epitopes. Vaccination with mature DC non-virally transfected with DNA encoding antigen had biological effect causing tumour regression and inducing diverse T lymphocyte responses.

Warfarin thromboprophylaxis in cancer patients with central venous catheters (WARP): an open-label randomised trial

BACKGROUND

The role and dose of anticoagulants in thromboprophylaxis for patients with cancer receiving chemotherapy through central venous catheters (CVCs) is controversial. We therefore assessed whether warfarin reduces catheter-related thrombosis compared with no warfarin and whether the dose of warfarin determines the thromboprophylactic effect.

METHODS

In 68 clinical centres in the UK, we randomly assigned 1590 patients aged at least 16 years with cancer who were receiving chemotherapy through CVCs to no warfarin, fixed-dose warfarin 1 mg per day, or dose-adjusted warfarin per day to maintain an international normalised ratio between 1.5 and 2.0. Clinicians who were certain of the benefit of warfarin randomly assigned patients to fixed-dose or dose-adjusted warfarin groups. The primary outcome was the rate of radiologically proven, symptomatic catheter-related thrombosis. Analysis was by intention to treat. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN 50312145.

FINDINGS

Compared with no warfarin (n=404), warfarin (n=408; 324 [79%] on fixed-dose and 84 [21%] on dose-adjusted) did not reduce the rate of catheter-related thromboses (24 [6%] vs 24 [6%]; relative risk 0.99, 95% CI 0.57-1.72, p=0.98). However, compared with fixed-dose warfarin (n=471), dose-adjusted warfarin (n=473) was superior in the prevention of catheter-related thromboses (13 [3%] vs 34 [7%]; 0.38, 0.20-0.71, p=0.002). Major bleeding events were rare; an excess was noted with warfarin compared with no warfarin (7 vs 1, p=0.07) and with dose-adjusted warfarin compared with fixed-dose warfarin (16 vs 7, p=0.09). A combined endpoint of thromboses and major bleeding showed no difference between comparisons. We did not note a survival benefit in either comparison.

INTERPRETATION

The findings show that prophylactic warfarin compared with no warfarin is not associated with a reduction in symptomatic catheter-related or other thromboses in patients with cancer and therefore we should consider newer treatments.

FUNDING

Medical Research Council and Cancer Research UK.

Sample size determination in clinical proteomic profiling experiments using mass spectrometry for class comparison

Mass spectrometric profiling approaches such as MALDI-TOF and SELDI-TOF are increasingly being used in disease marker discovery, particularly in the lower molecular weight proteome. However, little consideration has been given to the issue of sample size in experimental design. The aim of this study was to develop a protocol for the use of sample size calculations in proteomic profiling studies using MS. These sample size calculations can be based on a simple linear mixed model which allows the inclusion of estimates of biological and technical variation inherent in the experiment. The use of a pilot experiment to estimate these components of variance is investigated and is shown to work well when compared with larger studies. Examination of data from a number of studies using different sample types and different chromatographic surfaces shows the need for sample- and preparation-specific sample size calculations.

Estimating the cost-effectiveness of an intervention in a clinical trial when partial cost information is available: a Bayesian approach

There is an increasing need to establish whether health-care interventions are cost effective as well as clinically effective. It is becoming increasingly common for cost studies to be incorporated into clinical trials, either on all patients or more usually on a subset of patients. Establishing the total cost per patient is complex, as it requires information on resource use, which may come from a variety of different sources. This complexity may lead to considerable missing data, and can result in some patients only having partial cost information. In this paper we consider a clinical trial consisting of 351 patients with advanced non-small cell lung cancer comparing chemotherapy with standard palliative care. A subset of 115 patients was selected for the cost sub-study. Total cost was split into four components, for which resource use was collected. Complete resource data were available on 82 patients. For the remaining patients at least one of the cost components was missing. The objective of this paper is to develop a Bayesian approach which simultaneously models both the clinical effectiveness data and the cost data, by modelling the individual components. This also provides estimates of the cost-effectiveness in terms of the Incremental Net Monetary Benefit (INMB) and Cost-Effectiveness Acceptability Curves (CEAC). We compare a number of different models of increasing complexity. The models estimate the interrelationships between the four cost components and survival, and thus enable a predictive distribution for each missing cost item to be obtained.

Narrow-band imaging flexible cystoscopy in the detection of recurrent urothelial cancer of the bladder

OBJECTIVE

To investigate whether narrow-band imaging (NBI) flexible cystoscopy improves the detection rate of urothelial carcinomas (UCs) of the bladder. NBI is an optical image enhancement technology in which the narrow bandwidth of light is strongly absorbed by haemoglobin and penetrates only the surface of tissue, increasing the visibility of capillaries and other delicate tissue surface structures by enhancing contrast between the two.

PATIENTS AND METHODS

Between November 2005 and May 2007 at the Queen Elizabeth Hospital, Birmingham, NBI flexible cystoscopy was performed on 29 patients with known recurrences of UC of the bladder after initial conventional white-light imaging (WLI) flexible cystoscopy with the same instrument (Olympus Lucera sequential RGB endoscopy system).

RESULTS

Subjectively, NBI provided a much clearer view of bladder UCs and in particular their delicate capillary architecture. Objectively, NBI detected 15 additional UCs in 12 of 29 patients (41%), as compared with WLI. The mean (sd) difference was 0.52 (0.74) UCs per patient (P < 0.001, Wilcoxon signed-rank test).

CONCLUSIONS

Even in the few patients studied there is strong evidence that NBI differs from WLI in the number of UCs it detects, with a significantly increased detection rate. We feel that further evaluation of NBI flexible cystoscopy in more patients will show this technique to be highly valuable in the detection of both new and recurrent bladder UCs, and this work is continuing in our unit.

Rational Selection of Patients for Antibacterial Prophylaxis After Chemotherapy

Purpose

The SIGNIFICANT (Simple Investigation in Neutropenic Individuals of the Frequency of Infection after Chemotherapy ± Antibiotic in a Number of Tumours) trial reported a reduction in febrile episodes (FEs) among 1,565 patients with solid cancers and lymphomas receiving cyclical, myelosuppressive chemotherapy (causing grade 4 neutropenia) in a randomized, placebo-controlled, double-blind trial of levofloxacin (P = .01). In response to concerns that increased antibacterial prescribing selects for microbial resistance, we examined our data to explore the rationale for more limited prophylaxis.

Patients and Methods

The risk of FE was calculated for control patients on first versus nonfirst cycles, with or without first-cycle FE, and within subgroups defined by cancer type, performance status (PS), age, and treatment context (adjuvant v nonadjuvant). Using the randomized trial data, the prophylactic efficacy of levofloxacin was examined for the same subgroups.

Results

The per-cycle FE incidence was much lower on nonfirst (3.3%) versus first cycles (8.0%). Prophylaxis was less effective for nonfirst (odds ratio [OR] = 0.78; P = .16) compared with first cycles (OR = 0.42; P < .001). However, FE on cycle 1 predicted a much higher risk of FE and a trend to continued prophylactic efficacy on subsequent cycles. FE rate was greatest for testicular cancer (27.9%), then small-cell lung cancer (17.3%), and lowest for breast cancer (11.5%). Prophylactic efficacy was consistent across age, sex, PS, treatment context, and disease type (except possibly non-Hodgkin's lymphoma).

Conclusion

Under pressure to limit antibacterial use, these exploratory data support offering prophylactic levofloxacin on cycle 1 only of myelosuppressive cancer chemotherapy and on subsequent cycles after a cycle-1 fever. Prophylactic levofloxacin is effective regardless of age, PS, or tumor type.

Multiple testing issues in discriminating compound-related peaks and chromatograms from high frequency noise, spikes and solvent-based noise in LC-MS data sets

Liquid Chromatography--Mass Spectrometry (LC-MS) is a powerful method for sensitive detection and quantification of proteins and peptides in complex biological fluids like serum. LC-MS produces complex data sets, consisting of some hundreds of millions of data points per sample at a resolution of 0.1 amu in the m/z domain and 7000 data points in the time domain. However, the detection of the lower abundance proteins from this data is hampered by the presence of artefacts, such as high frequency noise and spikes. Moreover, not all of the tens of thousands of the chromatograms produced per sample are relevant for the pursuit of the biomarkers. Thus in analysing the LC-MS data, two critical pre-processing issues arise. Which of the thousands of the: 1. chromatograms per sample are relevant for the detection of the biomarkers?, and 2. signals per chromatogram are truly compound-related? Each of these issues involves assessing the significance (deviation from noise) of multiple observations and the issue of multiple comparisons arises. Current methods disregard the multiplicity and provide no concrete threshold for significance. However, with such procedures, the probability of one or more false-positives is high as the number of tests to be performed is large, and must be controlled. Realizing that the cut-offs for declaring a chromatogram (or a signal) to be compound-related can hugely influence which proteins are detected, it seems natural to define thresholds that are neither arbitrary nor subjective. We suggest the choice of thresholds guided by the critical aim of controlling the False Discovery Rate (FDR) in multiple hypotheses testing for significance over a large set of features produced per sample. This involves the use of the regression diagnostics to characterize the signals of a chromatogram (e.g. as outliers or influential) and to suggest suitable tests statistics for the multiple testing procedures (MTP) for discriminating noise and spikes from true signals. The role of the Generalized Linear Models (GLM) in this MTP is investigated. The method is applied to LC-MS datasets from trypsin-digested serum spiked with varying levels of horse heart cytochrome C (cytoc).

Plasma proteome analysis reveals the geographical origin and liver tumor status of Dab (Limanda limanda) from UK marine waters

The flatfish species dab (Limanda limanda) is the sentinel for offshore marine monitoring in the United Kingdom National Marine Monitoring Programme (NMMP). At certain sites in the North and Irish Seas, the prevalence of macroscopic liver tumors can exceed 10%. The plasma proteome of these fish potentially contains reporter proteins or "biomarkers" that may enable development of diagnostic tests for liver cancer and further our understanding of the disease. Following selection of sample groups by quality-assured histopathology ("phenotype anchoring"), we used surface-enhanced laser desorption/ionization (SELDI) time-of-flight mass spectrometry to produce proteomic profiles of plasma from 213 dab collected during the 2004 UK NMMP. The resulting protein profiles were compared between fish from the North and Irish Seas and between fish with liver neoplasia or nondiseased liver. Significant differences were found between the plasma proteomes of dab from the North Sea and Irish Sea, which in conjunction with artificial neural networks can correctly determine from which sea dab were captured in 85% of the cases. In addition, the presence of liver tumors is associated with significant changes in the plasma proteome. We conclude that SELDI-based plasma profiling is potentially of use in nonlethal marine monitoring using wild sentinels such as dab. Furthermore, accurate selection of sample groups is critical for avoiding effects of confounding factors such as age, gender, and geographic origin of samples.

Identification of serum biomarkers for colon cancer by proteomic analysis

Colorectal cancer (CRC) is often diagnosed at a late stage with concomitant poor prognosis. Early detection greatly improves prognosis; however, the invasive, unpleasant and inconvenient nature of current diagnostic procedures limits their applicability. No serum-based test is currently of sufficient sensitivity or specificity for widespread use. In the best currently available blood test, carcinoembryonic antigen exhibits low sensitivity and specificity particularly in the setting of early disease. Hence, there is great need for new biomarkers for early detection of CRC. We have used surface-enhanced laser desorbtion/ionisation (SELDI) to investigate the serum proteome of 62 CRC patients and 31 noncancer subjects. We have identified proteins (complement C3a des-arg, α1-antitrypsin and transferrin) with diagnostic potential. Artificial neural networks trained using only the intensities of the SELDI peaks corresponding to identified proteins were able to classify the patients used in this study with 95% sensitivity and 91% specificity.

Changes in the serum proteome associated with the development of hepatocellular carcinoma in hepatitis C-related cirrhosis

Early diagnosis of hepatocellular carcinoma (HCC) is the key to the delivery of effective therapies. The conventional serological diagnostic test, estimation of serum alpha-fetoprotein (AFP) lacks both sensitivity and specificity as a screening tool and improved tests are needed to complement ultrasound scanning, the major modality for surveillance of groups at high risk of HCC. We have analysed the serum proteome of 182 patients with hepatitis C-induced liver cirrhosis (77 with HCC) by surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry (SELDI). The patients were split into a training set (84 non-HCC, 60 HCC) and a ‘blind’ test set (21 non-HCC, 17 HCC). Neural networks developed on the training set were able to classify the blind test set with 94% sensitivity (95% CI 73–99%) and 86% specificity (95% CI 65–95%). Two of the SELDI peaks (23/23.5 kDa) were elevated by an average of 50% in the serum of HCC patients (P<0.001) and were identified as κ and λ immunoglobulin light chains. This approach may permit identification of several individual proteins, which, in combination, may offer a novel way to diagnose HCC.

Clinical trial design in hepatocellular carcinoma

Researchers interested in developing treatments for hepatocellular carcinoma (HCC) face three sets of problems; one set common to all clinical trialists at the beginning of the 21st century, one set related to phase I/II studies ('early drug development') and one set related to the design of phase III (randomised, controlled trials). This review is concerned with the challenges faced in designing high quality clinical trials in patients with HCC. Specific published trials are not discussed other than by way of illustration of the problems faced.

The effect of Epstein-Barr virus status on outcome in age- and sex-defined subgroups of patients with advanced Hodgkin's disease

BACKGROUND

Conflicting data on the effect of the Epstein-Barr virus (EBV) on outcome in Hodgkin's disease (HD) might be due to the heterogeneous nature of this disease. In this study we have investigated whether the effect of EBV status on outcome is different between aetiologically defined age groups (15-34, 35-44, 45+ years) and also between males and females.

PATIENTS AND METHODS

Paraffin-embedded sections from 273 patients with advanced HD from two related clinical trials were analysed for the presence of EBV using in situ hybridisation.

RESULTS

EBV was detected in 78 (29%) of cases. For all patients, after a median follow-up of 5 years, there were no significant differences in survival by EBV status although there was a trend towards longer failure-free survival times for EBV-positive patients. Multivariate analyses suggested that EBV and sex, when in combination, were prognostic factors for failure-free survival (P = 0.06 for both). For subgroups, the effect of EBV on failure-free survival was significant for males and 15-34 years age group (P = 0.05 and P = 0.03, respectively).

CONCLUSION

This study suggests that with a median follow-up of 5 years, EBV status does not affect survival but being EBV-positive may be beneficial in terms of failure-free survival, particularly for males and younger adults.

Patterns, costs and cost-effectiveness of care in a trial of chemotherapy for advanced non-small cell lung cancer

In a recently published randomised trial of chemotherapy versus palliative care in advanced non-small cell lung cancer (the MIC2 trial), chemotherapy was shown to prolong survival without compromising quality of life. The study presented here examines patterns of care and their associated costs within a representative subgroup of patients from the MIC2 trial. The study consisted of 116 patients from the South Birmingham Health Authority area. The total health service cost for each patient from entry to trial to death or last follow-up was calculated by combining the resources used with their associated unit costs. The mean cost for patients with complete data on the chemotherapy arm was 6999 pounds sterling (standard deviation (S.D.) 4194 pounds sterling) compared to 4076 pounds sterling (S.D. 3078 pounds sterling) for those with complete data on the palliative care arm. Non-parametric bootstrapping gave a difference between treatment arms in mean cost of 2924 pounds sterling(95% CI 1234 pounds sterling - 4323 pounds sterling). With a difference in mean survival of 2.4 months, this translates to an incremental cost-effectiveness ratio of 14,620 pounds sterling per life year gained. Chemotherapy was found to be more costly than standard palliative care, mainly due to the increased number of hospital in-patient days.

Interleukin 6 expression by Hodgkin/Reed-Sternberg cells is associated with the presence of 'B' symptoms and failure to achieve complete remission in patients with advanced Hodgkin's disease

Interleukin 6 (IL-6) is a potent immunomodulatory cytokine that has pathogenic and prognostic significance in a number of disorders. Previous studies in Hodgkin's disease (HD) have demonstrated the association between elevated serum levels of IL-6 and unfavourable prognosis, including advanced stage and the presence of 'B' symptoms and with reduced survival. Although IL-6 expression has been demonstrated in both the malignant Hodgkin/Reed-Sternberg (HRS) cells and in the various non-malignant cells present in HD biopsies, a relationship between expression of IL-6 by the tumour and outcome measures has not been established. The study group comprised of 97 patients with advanced HD who were recruited to two related clinical trials. IL-6 expression was determined on paraffin-wax sections of biopsy material by means of an immunohistochemical assay. Of the 97 patients, 27 (28%) showed staining for IL-6 in HRS cells. IL-6 expression by HRS cells was significantly correlated with a decreased likelihood of achieving a complete response to chemotherapy (P = 0.02) and with an increased prevalence of 'B' symptoms (P = 0.04). IL-6 expression by HRS cells was not associated with Epstein-Barr virus status (P = 0.57). In summary, the results suggest that IL-6 expression by HRS cells may contribute to the presence of 'B' symptoms and to a decreased likelihood to achieve a complete remission in HD patients.

Simultaneous analysis of quality of life and survival data

In many phase III clinical trials, particularly in the field of cancer, the comparison of treatments is based on both length of survival and quality of life. Subjects are followed over time until death and during this period, quality of life is assessed on a number of occasions. Simultaneous analysis of these two outcomes supplements the comparison of treatments in terms of each outcome independently with an assessment of the net effect. In addition, it provides a means of accounting for the informative dropout due to death of patients within the time frame of the quality of life study. The methods also have the potential to be extended to allow for informative dropout from the quality of life study prior to death. There are a number of broad approaches for the simultaneous analysis of quality of life and survival data. The most widely used approach in clinical research is quality-adjusted survival analysis, where treatments are compared in terms of a composite measure of quality and quantity of life. The paper reviews the different techniques for quality-adjusted survival analysis, illustrating the methodology by application to data from a phase III clinical trial in pancreatic cancer. In addition, alternative approaches using multistate survival analysis and joint modelling methods are also discussed.

The benefits of chemotherapy in patient subgroups with unresectable non-small-cell lung cancer

BACKGROUND

Cisplatin-based chemotherapy improves survival in advanced non-small-cell lung cancer. Using data from phase III trials of mitomycin, ifosfamide and cisplatin, this paper investigates whether the beneficial effect of chemotherapy on survival and quality of life seen overall is limited to certain patient subgroups.

PATIENTS AND METHODS

The survival benefit of chemotherapy was compared with standard treatment using hazard ratios for subgroups specified by stage, sex, age, histology and performance status (PS). The effect on quality of life was investigated for three subgroups defined by performance status.

RESULTS

The overall unstratified hazard ratio for all 797 eligible patients shows a 16% reduction in the risk of death with chemotherapy (P = 0.02). This benefit was seen for both locally advanced and extensive stage disease (significantly in extensive disease). Subgroups defined by sex, age and histology consistently benefitted from chemotherapy. The hazard ratios for the three levels of performance status suggest that PS2 patients gain no survival benefit from chemotherapy. In contrast, these patients experienced the greatest improvement in quality of life during the first six weeks of chemotherapy.

CONCLUSIONS

Subgroup analysis suggests that the prolongation of life from cisplatin-based chemotherapy is confined to PS0/1 patients. Palliation is greater in PS2 patients.

Palliative chemotherapy: no longer a contradiction in terms

Palliative chemotherapy is defined as treatment in circumstances where the impact of intervention is insufficient to result in major survival advantage, but does affect improvement in terms of tumor-related symptoms, and where the palliation/toxicity trade-off from treatment clearly favors symptom relief. The role of chemotherapy in circumstances where little or no survival benefit is anticipated remains controversial. This is despite the mounting body of evidence in favor of its use for symptom palliation. The notion persists that outcomes other than significant survival benefit are not valid, because of firmly held perceptions of toxicity. Studies of chemotherapeutic palliation using valid measures of quality of life, show that patients may be willing to accept some side effects of treatment, as long as they gain relief from tumor-related symptoms. The aims of this review are to present the case for palliative chemotherapy, to highlight the areas of progress which have made this feasible, and to provide guidance with regard to its appropriate use.

Mitomycin, ifosfamide, and cisplatin in unresectable non-small-cell lung cancer: effects on survival and quality of life

PURPOSE

Chemotherapy for non-small-cell lung cancer (NSCLC) remains controversial. We describe the two largest reported, randomized, parallel trials designed to determine whether the addition of chemotherapy influences duration and quality of life in localized, unresectable (mitomycin, ifosfamide, cisplatin [MIC]1 trial) and extensive (MIC2 trial) disease.

PATIENTS AND METHODS

Ambulatory patients with NSCLC, aged 75 years or younger, with localized disease, were randomized in MIC1 to receive up to four cycles of chemotherapy (CT: mitomycin 6 mg/m(2), ifosfamide 3 g/m(2), and cisplatin 50 mg/m(2)) every 21 days, followed by radical radiotherapy (CT + RT) or radiotherapy (RT) alone. Extensive-stage patients were randomized in MIC2 to identical chemotherapy plus palliative care (CT + PC) or palliative care (PC) alone. Short-term change in quality of life (QOL) was assessed in a subgroup of patients. Data from the two trials were combined to allow multivariate and stratified survival analyses.

RESULTS

Seven hundred ninety-seven eligible patients were randomized, 446 in MIC1 and 351 in MIC2. MIC CT improved survival in both trials (significantly in MIC2). The median survival time in MIC1 was 11.7 months (CT + RT) versus 9.7 months (RT alone) (P =.14); whereas in MIC2, median survival time was 6.7 months (CT + PC) compared with 4. 8 months (PC alone) (P =.03). QOL, assessed in 134 patients from start of trial to week 6, showed improvement with chemotherapy and deterioration with standard treatment. In the combined analysis of 797 randomized patients, the positive effect of MIC on survival was significant overall (P =.01) and after adjusting for prognostic factors (P =.01).

CONCLUSION

MIC chemotherapy prolongs survival in unresectable NSCLC without compromising QOL.

Effect of Epstein-Barr virus infection on response to chemotherapy and survival in Hodgkin's disease

We have analyzed paraffin sections from 190 patients with histologically confirmed Hodgkin's disease (HD) for the presence of Epstein-Barr virus (EBV) using in situ hybridization to detect the EBV-encoded Epstein-Barr virus early RNAs (EBERs) and immunohistochemistry to identify latent membrane protein-1 (LMP1) expression. EBV was present in the tumor cells in 51 HD cases (27%) and was mainly confined to the mixed cellularity and nodular sclerosis subtypes. There was no difference between EBV-positive and EBV-negative HD patients with regard to age, clinical stage, presentation, and the number of alternating chemotherapy cycles of ChIVPP and PABIOE received. The complete remission rate after study chemotherapy was 80% in EBV-positive patients versus 69% in EBV-negative patients (P =.05). The 2-year failure-free survival rate was significantly better for EBV-positive patients when compared with the EBV-negative HD group (P =.02). Although 2-year and 5-year overall survival rates were better for EBV-positive HD patients, the differences were not statistically significant (P =.18 and P =.40, respectively). In conclusion, the results confirm the favorable prognostic value of EBV in the tumor cells of HD patients and suggest important differences in response to chemotherapy between EBV-positive and EBV-negative patients.

Quality assurance of CFU-GM assays: inter-laboratory variation despite standard reagents

To investigate the hypothesis that commercial kits for CFU-GM (colony forming unit granulocyte-macrophage) assay will reduce the interlaboratory variation noted by many workers, we carried out a quality assurance exercise in 2 parts. There were 8 participants in the first study and each performed CFU-GM assays using their in-house method and a commercial kit (Stem Cell CFU Kit, Gibco) in parallel. In the second exercise there were 10 participants and each performed CFU-GM with in-house methods and with a different commercial medium (Methocult GF H4534, Stem Cell Technologies). Twelve samples of cryopreserved peripheral blood progenitor cells (PBPC) were analysed by each participant in each part of the study. A very wide range of results was found for the different in-house methods, but standardizing the clonogenic assay with the commercial kits did not reduce the variation seen. To improve the reproducibility of CFU-GM assays between laboratories, scrupulous attention should be paid to all the steps involved in the assays, as little progress will be made by using commercial medium in isolation from efforts to reduce other sources of variation.

Expression of E-cadherin in oesophageal carcinomas from the UK and China: disparities in prognostic significance

AIMS

To study the expression and prognostic significance of the cell adhesion molecule E-cadherin in oesophageal tumours from the UK (low risk area) and China (high risk area).

METHODS

E-cadherin expression was measured immunohistochemically in resected tumours from 17 patients in the UK with adenocarcinoma, 23 patients from the UK with squamous carcinoma, and 30 patients from China with squamous carcinomas who survived for five years postoperatively and compared with similar tumours from patients in the same regions who did not survive (140 tumours in all).

RESULTS

Normal squamous epithelial cells and well differentiated areas of tumours showed membranous staining for E-cadherin expression. Cytoplasmic staining, heterogeneous staining, or an absence of staining was seen in dysplastic epithelium and in less well differentiated areas of tumours. Only one of 140 primary tumours had homogeneous membranous expression. In tumours from UK patients with adenocarcinoma (p = 1.00) and from Chinese patients with squamous carcinomas (p = 0.06) there was no correlation between E-cadherin absence and non-survival. In tumours from UK patients with squamous carcinomas there was a significant correlation between absence of E-cadherin and non-survival (p = 0.009). Tumours from UK patients with squamous carcinoma who survived were significantly less likely to be E-cadherin absent than those from Chinese patients with squamous carcinomas who survived (p = 0.007). Multivariate analysis (n = 37 UK, paired data) showed that absence of E-cadherin in the primary tumour was a weak independent prognostic factor for non-survival (30% significance level; p = 0.26; odds ratio = 3.56). In UK nodal metastases there was no correlation between E-cadherin expression and survival.

CONCLUSIONS

Squamous carcinomas from UK patients differed from both adenocarcinomas from UK patients and carcinomas from Chinese patients with respect to E-cadherin expression and prognostic significance. In tumours from UK patients, E-cadherin absence in the primary carcinoma (a weak independent prognostic factor) but not metastases correlated with non-survival.

Colony counting is a major source of variation in CFU-GM results between centres

The results for colony forming unit granulocyte-macrophage (CFU-GM) assays vary substantially between centres. It is possible that colony counting is largely responsible for this discrepancy. In order to examine this exclusively from the many factors that make up the CFU-GM assay, we performed a colony counting exercise involving 11 laboratories. Two-way analysis of variance showed a highly significant difference (P = 0.0001) in the counts obtained from the centres. One centre was found to score consistently high and two others scored consistently low numbers of colonies. This suggests that identification of colonies is a major source of variation between centres.

Management preferences in stage I non-seminomatous germ cell tumours of the testis: an investigation among patients, controls and oncologists

Increasingly, treatment choices leading to the same survival outcome can be offered to cancer patients (e.g. mastectomy or conservative surgery in early breast cancer). Two approaches available for post-orchidectomy, stage I patients with non-seminomatous germ cell tumours of the testis (NSGCTT), particularly those at high risk of relapse, include immediate adjuvant chemotherapy (two courses) or surveillance, with chemotherapy (typically four courses) given only on relapse. The aim of this study was to investigate which approach patients prefer. Questionnaires were given to newly diagnosed NSGCTT patients, to patients with previous experience of the two options and to non-cancer controls, including specialist testicular tumour oncologists. Participants were asked to choose between immediate chemotherapy, surveillance or for the doctor to decide, at recurrence risk levels ranging from 10% to 90%. Questionnaires were returned by 207 subjects in nine different groups. The risk thresholds at which subjects' management preference changed, within apparently homogeneous groups, varied greatly, although at least one subject in each group selected adjuvant chemotherapy at the lowest (10%) level of risk. Subjects tended to favour options of which they had previous experience. Cancer patients wanted the doctor to decide more frequently than controls. The wide variability observed makes it difficult to predict which option an individual will select. Personality factors and personal circumstances, other than specific experience and knowledge, are obviously influential. Many patients would prefer their doctor to decide, but variability among oncologists is as great as that among their patients.

Quality assurance of CD34+ cell estimation in leucapheresis products

In order to examine the feasibility of an external quality assurance (QA) scheme for CD34+ cell enumeration and to identify causes of the differences between laboratories for CD34 counts, we carried out a pilot QA exercise in two parts. There were eight participating laboratories in the initial study and each performed CD34 counts using their in-house method. A series of 12 samples of cryopreserved peripheral blood progenitor cells (PBPC) were analysed by each of the eight laboratories. A very wide range of values for all the samples was found for the different in-house methods. For the second part of the study, 12 laboratories analysed a different set of 12 PBPC samples and each used the same anti-CD34 antibody (HPCA-2 PE), anti-CD45 antibodies to identify leucocytes, and counted a minimum of 50,000 events. These measures have reduced the interlaboratory variation in results but this variation is still too high to allow us to realistically compare values between centres. Overall, most centres performed comparably, but there was one centre in part one of the study which gave results that were significantly different from the other centres.

High lactate dehydrogenase level is associated with an adverse outlook in autografting for Hodgkin's disease

Forty-two patients with relapsed or refractory Hodgkin's disease (HD) were treated with high-dose chemotherapy (BEAM regimen) followed by autologous bone marrow and/or peripheral blood progenitor cell (PBPC) rescue. There was one procedure-related death and the overall response rate at 6 months was 88% (95% confidence interval 78-98%). The 2 year overall and event-free survival was 81% (95% confidence interval 65-96%) and 74% (95% confidence interval 58-89%) respectively. Median follow-up was 33 months. The use of PBPC instead of marrow resulted in a significant shortening of the time to engraftment (P < 0.01). Multivariate analysis identified the pre-transplant LDH level as a highly significant factor in predicting overall survival (P = 0.007). The BEAM regimen is an effective conditioning schedule that is well tolerated but patients with a raised LDH at the time of transplant remain at high risk of early relapse and death due to disease.