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Patient-reported quality of life (QoL) outcomes have the potential to assist clinicians in providing individually tailored treatment decisions. QoL assessments were collected prospectively for 168 consecutive patients treated for oral cancer between 1 January 2010 and 31 December 2014 using the University of Washington Quality of Life Questionnaire. Patients were followed up for 18 months post-treatment. Sub-group analyses were performed using paired t-tests and analysis of variance (ANOVA) to compare the effects of adjunctive chemoradiotherapy, type of bone resection, and methods of soft and hard tissue flap reconstruction. The greatest statistically significant reduction in QoL for all oral cavity sub-sites was found following the treatment of floor of mouth tumours (-18.9%, P=0.018). Laser excision for matched patient cohorts resulted in improved resultant QoL compared to other excision techniques (P=0.0002). No significant difference in QoL was found when radial forearm and anterolateral thigh flaps were matched, or when fibula and scapula flaps were matched. These findings support the use of laser excision and the avoidance of postoperative radiotherapy if curative intent and survival outcomes are maintained.

Health-related quality of life (QoL) reported by patients has the potential to improve care after ablative surgery of the midface, as existing treatment algorithms still generally revolve around outcomes assessed traditionally only by clinicians. Decisions in particular relate to reconstruction with a flap compared with rehabilitation with an obturator, the need for adjuvant treatment, and morbidity related to the size of the defect. We prospectively collected health-related QoL assessments for 39 consecutive patients treated by maxillectomy between 01 January 2010 and 31 December 2014 using the University of Washington Quality of Life Questionnaire, and who had a mean (SD) duration of follow-up of 14 (4). We made sub-group analyses using paired t tests and analysis of variance (ANOVA) to compare reconstruction with a flap with rehabilitation with obturators, size of the vertical defect, and whether adjuvant treatment with radiotherapy or chemoradiotherapy adversely affected it. Overall there was a significant decrease in health-related QoL after treatment compared with before (p

Objective: The main objective of this study was to determine whether bacteria cultured from oral swabs taken at the time of surgery predicted postoperative fistula formation. Design: The study was a prospective longitudinal audit. Setting: The setting was a designated U.K. N.H.S. cleft center. Patients: Subjects consisted of the patients of a single cleft surgeon who were undergoing surgery for cleft palate repair or cleft fistula repair. Interventions: Oral microbiological swabs were taken from patients while they were on the operating table just before surgery. Main outcome measures: The results from microbiological culture of the swabs were recorded, as was the presence or absence of a fistula at 6 months postoperatively. Additional collected information was related to the severity of the cleft, whether the operating microscope was used during surgery, and whether the patient had developed a postoperative upper respiratory tract infection. Results: Positive swab cultures were not significantly associated with fistula formation. Use of the operating microscope was not associated with an increase or decrease in the number of fistulas. A fistula developed in all patients who experienced a postoperative upper respiratory tract infection. Conclusions: The practice of performing routine preoperative mouth swabs should be abandoned because the presence of bacteria in the mouth does not increase the risk of fistula formation.

We propose a class of credit models where we model default intensity as a jump-diffusion stochastic process. We demonstrate how this class of models can be specialised to value multi-asset derivatives such as CDO and CDO2 in an efficient way. We also suggest how it can be adapted to the pricing of option on tranche and leverage tranche deals. We discuss how the model performs when calibrated to the market.

We present a case of isolated cardiac metastasis of oral squamous cell carcinoma. An 89-year-old woman was due to undergo curative resection of a histologically proven squamous cell carcinoma of the retromolar region. On admission, it was noted that there were ECG changes, and following further investigations, the patient was diagnosed with a cardiac metastasis of her oral malignancy. The presentation, including the diagnostic difficulties, as well as the clinical features of this rare case, are discussed.

Objective The objective of this study was to evaluate the quality of the dying experience in a cohort of head and neck cancer patients by a retrospective analysis of potential indicators of care. Study design The study design included retrospective case note analysis of previously evaluated factors considered important in the care of terminally ill patients and validated indicators of care obtainable from administrative data. The documented factors were analyzed to indicate specific elements of the quality of death and dying experience. Results Pain was a common symptom (84%) and was managed successfully in all patients, with 93% receiving opioids. Management of other symptoms, except neuropsychological problems, were satisfactory. Sixty-three percent of patients died in hospital and only 22% had a relative present at the time of death. Resuscitation status was documented in only 65% of the notes, though none were admitted to the intensive care unit or underwent resuscitation. Fifty-three percent of patients were admitted as an emergency in the last month of life and bleeding was the most common cause of admission. Conclusion Valuable information can be obtained from a focused retrospective analysis. The indicators evaluated suggest that biomedical aspects of care are being recognized and addressed, although there is room for improvement. Psychosocial and spiritual aspects of care were not documented and must be taken into account to assess the “complete quality of dying” experience.

The requirements for adequate cirrhotic liver biopsy size have not been established for quantitative fibrosis measurements (collagen proportionate area: CPA). We evaluated the CPA of virtual biopsies in cirrhosis to elucidate (i) the amount of tissue required to achieve reliable CPA measurements and (ii) the effect of aetiology on sample size requirements. A total of 120 cirrhotic tissue blocks (six aetiologies) were studied. A representative 100 mm(2) region was selected from each block and a reference CPA measured. Each image (n = 120) was divided into 100 × 1 mm(2) images; CPA was measured for each 1 mm(2) and virtual biopsies of different sizes were created from the 1 mm(2) components. For each virtual biopsy size the probability that the virtual biopsy CPA would be within 5% of the reference CPA was calculated. There were 441 000 virtual biopsies. Biopsy size versus probability plots indicated that, for 90% probability that the virtual biopsy CPA can be expected to be within 5% of the reference CPA, 22-28 mm(2) of analysable tissue is required depending on liver disease aetiology; and that a 75% probability level requires a biopsy with 12-15 mm(2) of analysable tissue. The sample size required for a given probability level depends on the aetiology of cirrhosis, and this should be taken into account when judging the reliability of cirrhotic liver biopsy CPA.

This article develops a methodology for valuing the counterparty credit risk inherent in credit default swaps, and presents a multi-dimensional extension of Merton's model (Merton 1974), where the joint dynamics of the firm's values are driven by a multi-dimensional jump-diffusion process. Applying the Fast Fourier Transform and finite-difference methods, it develops a forward induction procedure for calibrating the model, and a backward induction procedure for valuing credit derivatives in 1D and 2D. Jump size distributions of two types are considered, namely, discrete negative jumps (DNJs) and exponential negative jumps (ENJs), and showed that, for joint bivariate dynamics, the model with ENJs produces a noticeably lower implied Gaussian correlation than the one produced by the model with DNJs, although for both jump specifications the corresponding marginal dynamics fit the market data adequately. Based on these observations, and given the high level of the default correlation among financial institutions (above 50 per cent), the model with DNJs, albeit simple, seems to provide a more realistic description of default correlations and, thus, the counterparty risk, than a more sophisticated model with ENJs.

This article examines the conventional bond pricing methodology and shows that it does not adequately reflect the nature of the credit risk faced by investors. In particular, it demonstrates that the strippable discounted cash flows valuation assumption, which is normally taken for granted by most analysts, leads to biased estimates of relative value for credit bonds. The article introduces a consistent survival-based valuation methodology that is free of biases, albeit at a price of abandoning the strippable discounted cash flows valuation assumption, and also develops a robust estimation methodology for survival probability term structures using the exponential splines approximation. This methodology is implemented and tested in a wide variety of market conditions, and across a large set of sectors and issuers, from the highest credit quality to highly distressed ones. It concludes that the adoption of the survival-based methodologies advocated in this article by market participants will lead to an increase in the efficiency of the credit markets, just as the adoption of better pre-payment models led to efficiency in the mortgage-based securities markets twenty years ago.

This article, which provides the first complete exposition of the saddlepoint method to the calculation and management of portfolio losses, in an environment that is quite general and therefore applicable to many asset classes and many models, is divided into two parts. First, it discusses the construction of the distribution of losses, which is an essential ingredient of valuing collateralised debt obligation tranches and calculating risk measures at different levels of confidence. Second, the article examines where the risk is coming from, which more formally means the sensitivity of risk to asset allocation – an idea that is fundamental to portfolio theory and risk management, and which is at the heart of the Capital Asset Pricing Model.

This article begins with a brief discussion of how the current global credit crisis differs from previous ones, specifically in the form of the underlying relationship between borrowers and lenders, and then sets out the purpose of the book, which is to provide an overview of the complex and relatively novel area of mathematical modelling. Given the fact that mathematics entering into the analysis of credit risk was contemporaneous with unprecedented growth in the credit markets and thus preceded the crash, it is not surprising that many view mathematics as the cause of the crisis. It is argued that, despite the inevitable shortcomings of each mathematical model used, mathematics was not the cause of the current difficulties.

Levy Simple Structural Models (M Baxter) Cluster-Based Extension of the Generalized Poisson Loss Dynamics and Consistency with Single Names (D Brigo et al.) Stochastic Intensity Modeling for Structured Credit Exotics (A Chaposvsky et al.) Large Portfolio Credit Risk Modeling (M H A Davis & J C Esparragoza-Rodriguez) Empirical Copulas for CDO Tranche Pricing Using Relative Entropy (M Dempster et al.) Pricing and Hedging in a Dynamic Credit Model (Y Elouerkhaoui) Joint Distributions of Portfolio Losses and Exotic Portfolio Products (F Epple et al.) On the Term Structure of Loss Distributions: A Forward Model Approach (J Sidenius).

The frontiers of drilling in harsh environments are continually being pushed back. Since 1994, drilling rigs have successfully operated at all times of the year in the deep waters of the Northeast Atlantic Margin. Lessons learned from experience in these hostile waters are guiding rig development. The Sovereign Explorer, a GVA 4000 design, was the first rig to operate around the year in the area and in water depths greater than 1500 ft during 1994 and 1995. As a result of this experience, extensive rig riser modifications were made to facilitate operation in the stronger-than-expected currents before a second round of drilling. A riser recoil system was installed to allow a controlled retraction of the slip joint during disconnection of the lower marine riser package (LMRP), and additional riser tensioners were fitted to reduce tensioning system operating stress levels. Further modifications are planned, including active heave compensation and an improved BOP control system. Heave compensation will allow the Lower Marine Riser Package (LMRP) to be re-latched in 8- to 12-ft heave conditions rather than 4- to 6-ft heave, with an estimated saving of seven rig days per year. Improved BOP control, together with other modifications, will extend the rig's water depth limit to 4500 ft. The challenges set by the difficult operating conditions encountered in the Northeast Atlantic Margin are discussed, together with some of the solutions already tested and other developments proposed.

The rewards and dangers of speculating in the modern financial markets have come to the fore in recent times with the collapse of banks and bankruptcies of public corporations as a direct result of ill-judged investment. At the same time, individuals are paid huge sums to use their mathematical skills to make well-judged investment decisions. Here now is the first rigorous and accessible account of the mathematics behind the pricing, construction and hedging of derivative securities. Key concepts such as martingales, change of measure, and the Heath-Jarrow-Morton model are described with mathematical precision in a style tailored for market practitioners. Starting from discrete-time hedging on binary trees, continuous-time stock models (including Black-Scholes) are developed. Practicalities are stressed, including examples from stock, currency and interest rate markets, all accompanied by graphical illustrations with realistic data. A full glossary of probabilistic and financial terms is provided. This unique, modern and up-to-date book will be an essential purchase for market practitioners, quantitative analysts, and derivatives traders, whether existing or trainees, in investment banks in the major financial centres throughout the world.

In recent years there has been much interest in the use of optical diagnostics in cancer detection. Early diagnosis of cancer affords early intervention and greatest chance of cure. Raman spectroscopy is based on the interaction of photons with the target material producing a highly detailed biochemical 'fingerprint' of the sample. It can be appreciated that such a sensitive biochemical detection system could confer diagnostic benefit in a clinical setting. Raman has been used successfully in key health areas such as cardiovascular diseases, and dental care but there is a paucity of literature on Raman spectroscopy in Head and Neck cancer. Following the introduction of health care targets for cancer, and with an ever-aging population the need for rapid cancer detection has never been greater. Raman spectroscopy could confer great patient benefit with early, rapid and accurate diagnosis. This technique is almost labour free without the need for sample preparation. It could reduce the need for whole pathological specimen examination, in theatre it could help to determine margin status, and finally peripheral blood diagnosis may be an achievable target.