A comparative study of analytical models of diffuse reflectance in homogeneous biological tissues: Gelatin-based phantoms and Monte Carlo experiments

Information about tissue oxygen saturation (StO2) and other related important physiological parameters can be extracted from diffuse reflectance spectra measured through non-contact imaging. Three analytical optical reflectance models for homogeneous, semi-infinite, tissue have been proposed (Modified Beer-Lambert, Jacques 1999, Yudovsky 2009) but these have not been directly compared for tissue parameter extraction purposes. We compare these analytical models using Monte Carlo (MC) simulated diffuse reflectance spectra and controlled gelatin-based phantoms with measured diffuse reflectance spectra and known ground truth composition parameters. The Yudovsky model performed best against MC simulations and measured spectra of tissue phantoms in terms of goodness of fit and parameter extraction accuracy followed closely by Jacques' model. In this study, Yudovsky's model appeared most robust; however, our results demonstrated that both Yudovsky and Jacques models are suitable for modeling tissue that can be approximated as a single, homogeneous, semi-infinite slab.

Modified transseptal approach in endoscopic transsphenoidal pituitary surgery

OBJECTIVE

Transsphenoidal pituitary surgery is commonly performed via a direct transostial approach with a posterior septectomy. However, a technique via an endoscopic transseptal route has been described that avoids a posterior septectomy, but it comes with its own disadvantages.

METHODS

This paper describes a modification, and discusses its pros and cons.

RESULTS

The initial incision in the mucosa is placed level with the anterior middle turbinate. The mucoperichondrial flap is raised ipsilaterally until the sphenoid sinus ostium. An incision is made at the osseocartilaginous junction, and the contralateral mucoperichondrial flap is raised. The bony septum and posterior aspect of this flap is excised. The size and position of this window can be adapted. At the end of the operation, the lateralised intact mucoperichondrial flap is moved back to the midline.

CONCLUSION

Excision or deflection of the cartilaginous septum is not required. It maintains an intact septal mucosa on one side and avoids a septal perforation.

Lightfield hyperspectral imaging in neuro-oncology surgery: an IDEAL 0 and 1 study

Introduction

Hyperspectral imaging (HSI) has shown promise in the field of intra-operative imaging and tissue differentiation as it carries the capability to provide real-time information invisible to the naked eye whilst remaining label free. Previous iterations of intra-operative HSI systems have shown limitations, either due to carrying a large footprint limiting ease of use within the confines of a neurosurgical theater environment, having a slow image acquisition time, or by compromising spatial/spectral resolution in favor of improvements to the surgical workflow. Lightfield hyperspectral imaging is a novel technique that has the potential to facilitate video rate image acquisition whilst maintaining a high spectral resolution. Our pre-clinical and first-in-human studies (IDEAL 0 and 1, respectively) demonstrate the necessary steps leading to the first in-vivo use of a real-time lightfield hyperspectral system in neuro-oncology surgery.

Methods

A lightfield hyperspectral camera (Cubert Ultris ×50) was integrated in a bespoke imaging system setup so that it could be safely adopted into the open neurosurgical workflow whilst maintaining sterility. Our system allowed the surgeon to capture in-vivo hyperspectral data (155 bands, 350-1,000 nm) at 1.5 Hz. Following successful implementation in a pre-clinical setup (IDEAL 0), our system was evaluated during brain tumor surgery in a single patient to remove a posterior fossa meningioma (IDEAL 1). Feedback from the theater team was analyzed and incorporated in a follow-up design aimed at implementing an IDEAL 2a study.

Results

Focusing on our IDEAL 1 study results, hyperspectral information was acquired from the cerebellum and associated meningioma with minimal disruption to the neurosurgical workflow. To the best of our knowledge, this is the first demonstration of HSI acquisition with 100+ spectral bands at a frame rate over 1Hz in surgery.

Discussion

This work demonstrated that a lightfield hyperspectral imaging system not only meets the design criteria and specifications outlined in an IDEAL-0 (pre-clinical) study, but also that it can translate into clinical practice as illustrated by a successful first in human study (IDEAL 1). This opens doors for further development and optimisation, given the increasing evidence that hyperspectral imaging can provide live, wide-field, and label-free intra-operative imaging and tissue differentiation.

A role for androgen receptor variant 7 in sensitivity to therapy: Involvement of IGFBP-2 and FOXA1

Prostate cancer (PCa) is one of the leading causes of cancer-related deaths in men. Localised PCa can be treated effectively, but most patients relapse/progress to more aggressive disease. One possible mechanism underlying this progression is alternative splicing of the androgen receptor, with AR variant 7(ARV7) considered to play a major role. Using viability assays, we confirmed that ARV7-positive PCa cells were less sensitive to treatment with cabazitaxel and an anti-androgen-enzalutamide. Also, using live-holographic imaging, we showed that PCa cells with ARV7 exhibited an increased rate of cell division, proliferation, and motility, which could potentially contribute to a more aggressive phenotype. Furthermore, protein analysis demonstrated that ARV7 knock-down was associated with a decrease in insulin-like growth factor-2 (IGFBP-2) and forkhead box protein A1(FOXA1). This correlation was confirmed in-vivo using PCa tissue samples. Spearman rank correlation analysis showed significant positive associations between ARV7 and IGFBP-2 or FOXA1 in tissue from patients with PCa. This association was not present with the AR. These data suggest an interplay of FOXA1 and IGFBP-2 with ARV7-mediated acquisition of an aggressive prostate cancer phenotype.

Synthetic white balancing for intra-operative hyperspectral imaging

Purpose

Hyperspectral imaging shows promise for surgical applications to non-invasively provide spatially resolved, spectral information. For calibration purposes, a white reference image of a highly reflective Lambertian surface should be obtained under the same imaging conditions. Standard white references are not sterilizable and so are unsuitable for surgical environments. We demonstrate the necessity for in situ white references and address this by proposing a novel, sterile, synthetic reference construction algorithm.

Approach

The use of references obtained at different distances and lighting conditions to the subject were examined. Spectral and color reconstructions were compared with standard measurements qualitatively and quantitatively, using ΔE and normalized RMSE, respectively. The algorithm forms a composite image from a video of a standard sterile ruler, whose imperfect reflectivity is compensated for. The reference is modeled as the product of independent spatial and spectral components, and a scalar factor accounting for gain, exposure, and light intensity. Evaluation of synthetic references against ideal but non-sterile references is performed using the same metrics alongside pixel-by-pixel errors. Finally, intraoperative integration is assessed though cadaveric experiments.

Results

Improper white balancing leads to increases in all quantitative and qualitative errors. Synthetic references achieve median pixel-by-pixel errors lower than 6.5% and produce similar reconstructions and errors to an ideal reference. The algorithm integrated well into surgical workflow, achieving median pixel-by-pixel errors of 4.77% while maintaining good spectral and color reconstruction.

Conclusions

We demonstrate the importance of in situ white referencing and present a novel synthetic referencing algorithm. This algorithm is suitable for surgery while maintaining the quality of classical data reconstruction.

Carpal Tunnel Decompression Under Wide Awake Local Anaesthesia No Tourniquet Technique (WALANT): A Cost Effective and Outcome Analysis

Introduction Wide-awake local anaesthesia with no tourniquet (WALANT) technique is cost-effective, resource-friendly, and safe. This can be used as an alternative to hand surgery procedures in outpatient units. It can be performed in clinics or operating rooms. Methods We retrospectively evaluated the outcomes of WALANT for carpal tunnel decompression (CTD) over two years. Measured results include wound infections, relief of symptoms, paraesthesia, haematoma, Visual Analogue Scale (VAS), hospital anxiety and depression scale score (HADS) and cost-effectiveness. Results Eighteen patients underwent CTD under the WALANT technique over two years. VAS score was recorded at 3.1 ± 1.2 during the procedure and 1.67 ± 0.933 at two weeks follow-up. Persistent paraesthesia was found in only one patient at follow-up. Minimal bleeding was recorded during the procedure. No wound infections, revision surgery or post-operative haematoma formation were found. Hospital Anxiety and Depression Scale (HADS) was reported as 4.77 ± 2.1 after surgery. WALANT was also cost-effective, with an overall amount of £20. Conclusion Performing carpal tunnel decompression under WALANT in one stop upper limb clinic is a safe and cost-effective technique with no significant patient-related complications.

Deep learning approach for hyperspectral image demosaicking, spectral correction and high-resolution RGB reconstruction

Hyperspectral imaging is one of the most promising techniques for intraoperative tissue characterisation. Snapshot mosaic cameras, which can capture hyperspectral data in a single exposure, have the potential to make a real-time hyperspectral imaging system for surgical decision-making possible. However, optimal exploitation of the captured data requires solving an ill-posed demosaicking problem and applying additional spectral corrections. In this work, we propose a supervised learning-based image demosaicking algorithm for snapshot hyperspectral images. Due to the lack of publicly available medical images acquired with snapshot mosaic cameras, a synthetic image generation approach is proposed to simulate snapshot images from existing medical image datasets captured by high-resolution, but slow, hyperspectral imaging devices. Image reconstruction is achieved using convolutional neural networks for hyperspectral image super-resolution, followed by spectral correction using a sensor-specific calibration matrix. The results are evaluated both quantitatively and qualitatively, showing clear improvements in image quality compared to a baseline demosaicking method using linear interpolation. Moreover, the fast processing time of 45 ms of our algorithm to obtain super-resolved RGB or oxygenation saturation maps per image for a state-of-the-art snapshot mosaic camera demonstrates the potential for its seamless integration into real-time surgical hyperspectral imaging applications.

COVID-19 Infection in a 13-year-old Heart Transplant Recipient in Immediate Post Transplant Period - A Case Report

Introduction

Experience regarding course and outcome of Covid-19 infection in heart transplant recipients is limited. Case fatality rate of 25% of covid-19 infection in adult recipients of heart transplant and mild and self-limited disease in young heart transplant patients have been reported in small case series. We describe a case where a 13 year old patient contracted covid-19 infection on 7^th post-operative day after undergoing heart transplant and was subsequently discharged from hospital uneventfully.

Case Report

A 13 year old boy, with dilated cardiomyopathy underwent orthotopic heart transplant surgery. In the immediate pre-operative period, the real-time polymerase chain reaction (RTPCR) of nasopharyngeal swabs of both the recipient and the brain-dead organ donor were negative for severe acute respiratory syndrome coronavirus type 2 (SARS CoV 2). The intraoperative and immediate postoperative periods were uneventful. The recipient got weaned off from mechanical ventilation on the 1^st postoperative day and O₂ support was weaned off on 4^th postoperative day. He was put on immunosuppressive regimen consisting of mycophenolate mofetil, tacrolimus and prednisone. On 7^th postoperative day, he complained of fever, sore throat and dry cough. Nasopharyngeal swab for RTPCR was sent. It reported positive for SARS CoV 2. He was shifted to isolation facility. He maintained more than 94% saturation on pulse oximetry in room air. Immunosuppressive regimen was continued. He was administered 5-day course of remdesivir. Inotropic support was weaned off on 10^th postoperative day. On serial bedside echocardiography, the allograft function was found to be normal throughout. He was kept on prophylactic antimicrobial, antifungal and anti-cytomegaloviral therapy and on prophylactic dose of low molecular weight heparin. There was initial rise in neutrophil lymphocyte ratio (17), C reactive protein (58 mg/l), ferritin (871 ng/ml), D-dimer (1904 ng/ml), Troponin T (227 pg/ml) levels, which gradually came down to within normal limits. He was discharged on 38^th postoperative day to a home isolation facility as his RTPCR for SARS CoV 2 was still positive, although he remained completely asymptomatic for the last 21 days.

Summary

The course of Covid-19 infection in the immediate post-transplant period of this young heart transplant recipient was largely uneventful.

Prospective observational study evaluating acute and delayed treatment related toxicities of prophylactic extended field volumetric modulated arc therapy with concurrent cisplatin in cervical cancer patients with pelvic lymph node metastasis

PURPOSE

To evaluate the treatment related acute and delayed toxicities of extended field Volumetric modulated arc therapy (VMAT) with concurrent chemotherapy in patients of locally advanced cervical cancer with pelvic lymph nodes.

MATERIAL AND METHODS

From 2014 to 2016, 15 patients of locally advanced cervical cancer with Fluoro-deoxyglucose positron emission tomography (FDG-PET) positive pelvic lymph nodes were treated with extended field Simultaneous integrated boost (SIB)-VMAT 45 Gy/55 Gy/25#/5weeks and concurrent cisplatin. Acute toxicities were documented according to common terminology criteria for adverse events version 4 (CTCAE v.4). Dose volume parameters and patient characteristics were analyzed for association with toxicities.

RESULTS

Median age of patients at diagnosis was 48 years. 40% (6 patients) were stage IIB & 60% (9 patients) were stage IIIB. Median number of involved pelvic lymph nodes was 2 (range, 1-4), commonest location was external iliac lymph node region (86%). Median number of concurrent chemotherapy cycles received was five. Treatment was well tolerated and there were no grade ≥ 3 acute toxicities. Commonest acute toxicities observed were vomiting (≥grade2 -13.3%) followed by & nausea (grade ≥ 2 in 6%) and were associated with volume of bowel bag receiving 45 Gy. Constitutional symptoms (≥grade 2) were observed in 6% patients and had no dosimetric associations. At a median follow up of 43 months, delayed ≥ grade1, 2, 3 toxicity were observed in 80%, 0%, and 0% respectively with diarrhea being the commonest.

CONCLUSION

Prophylactic para aortic extended field VMAT with concurrent chemotherapy for locally advanced cervical cancer is well tolerated with acceptable acute toxicity profile. Significant grade 3 acute/delayed toxicities were not observed in this cohort of patients.

Accurate real-time FENO expirograms using complementary optical sensors

The fraction of exhaled nitric oxide (F_ENO) is an important biomarker for the diagnosis and management of asthma and other pulmonary diseases associated with airway inflammation. In this study we report on a novel method for accurate, highly time-resolved, real time detection of F_ENO at the mouth. The experimental arrangement is based on a combination of optical sensors for the determination of the temporal profile of exhaled NO and CO₂ concentrations. Breath CO₂ and exhalation flow are measured at the mouth using diode laser absorption spectroscopy (at 2 μm) and differential pressure sensing, respectively. NO is determined in a sidestream configuration using a quantum cascade laser based, cavity-enhanced absorption cell (at 5.2 μm) which simultaneously measures sidestream CO₂. The at-mouth and sidestream CO₂ measurements are used to enable the deconvolution of the sidestream NO measurement back to the at-mouth location. All measurements have a time resolution of 0.1 s, limited by the requirement of a reasonable limit of detection for the NO measurement, which on this timescale is 4.7 ppb (2 σ). Using this methodology, NO expirograms (F_ENOgrams) were measured and compared for eight healthy volunteers. The F_ENOgrams appear to differ qualitatively between individuals and the hope is that the dynamic information encoded in these F_ENOgrams will provide valuable additional insight into the location of the inflammation in the airways and potentially predict a response to therapy. A validation of the measurements at low-time resolution is provided by checking that results from previous studies that used a two-compartment model of NO production can be reproduced using our technology.

Bound-Electron Nonlinearity Beyond the Ionization Threshold

We present absolute space- and time-resolved measurements of the ultrafast laser-driven nonlinear polarizability in argon, krypton, xenon, nitrogen, and oxygen up to ionization fractions of a few percent. These measurements enable determination of the strongly nonperturbative bound-electron nonlinear polarizability well beyond the ionization threshold, where it is found to remain approximately quadratic in the laser field, a result normally expected at much lower intensities where perturbation theory applies.

Inhibition of FASN and ERα signalling during hyperglycaemia-induced matrix-specific EMT promotes breast cancer cell invasion via a caveolin-1-dependent mechanism

Since disturbed metabolic conditions such as obesity and diabetes can be critical determinants of breast cancer progression and therapeutic failure, we aimed to determine the mechanism responsible for their pro-oncogenic effects. Using non-invasive, epithelial-like ERα-positive MCF-7 and T47D human breast cancer cells we found that hyperglycaemia induced epithelial to mesenchymal transition (EMT), a key programme responsible for the development of metastatic disease. This was demonstrated by loss of the epithelial marker E-cadherin together with increases in mesenchymal markers such as vimentin, fibronectin and the transcription factor SLUG, together with an enhancement of cell growth and invasion. These phenotypic changes were only observed with cells grown on fibronectin and not with those plated on collagen. Analyzing metabolic parameters, we found that hyperglycaemia-induced, matrix-specific EMT promoted the Warburg effect by upregulating glucose uptake, lactate release and specific glycolytic enzymes and transporters. We showed that silencing of fatty acid synthase (FASN) and the downstream ERα, which we showed previously to mediate hyperglycaemia-induced chemoresistance in these cells, resulted in suppression of cell growth: however, this also resulted in a dramatic enhancement of cell invasion and SLUG mRNA levels via a novel caveolin-1-dependent mechanism.

Practical consensus recommendations regarding the management of HER2 neu positive early breast cancer

Over-expression of HER2 is generally considered to be a negative prognostic feature because it accompanies an increase in breast cancer mortality. However, the development of agents that specifically target HER2 has improved the management of patients with these tumours. This expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at these practical consensus recommendations with regards to the use of these agents and the management of HER2 neu early breast cancer for the benefit of community oncologists.

Ability of computed tomography to predict right heart strain on an echocardiogram in patients with acute pulmonary embolus

Patients with submassive pulmonary embolism (PE) resulting in right heart strain (RHS) have an increased risk of mortality compared to those with a preserved right ventricular function. This study aimed to investigate the predictive value of computed tomography pulmonary angiogram (CTPA) findings of right heart strain in patients with computed tomography (CT)-proven PE for the diagnosis of right heart strain by echocardiogram (ECHO). The institutional review board (IRB) approved retrospective chart review of the adult emergency department patients diagnosed with an acute PE between 2012 and 2016. A total of 128 patients diagnosed with RHS by CT who had received an ECHO during their hospitalization were included in the study. Descriptive statistics were run for the variables of interest. The majority of patients (101 patients) with reported findings of RHS on CT had similar findings on ECHO. In our cohort, a finding of enlarged right atrium (RA) on CT was 100% predictive of RHS diagnosis on ECHO, whereas having interventricular septal bowing alone on CT was the least predictive of RHS on subsequent ECHO (61%). The 2 remaining subgroups: right ventricle (RV) enlargement alone and RV enlargement with either interventricular septal bowing/hepatic vein blood reflux or both lies somewhere in between, with 80% of these patients showing strain on ECHO. We found that signs of RHS on CT are predictive of strain on an ECHO (78%) and RA enlargement in any combination was the most predictive finding of RHS on ECHO (100%). Future prospective randomized investigations are needed to confirm such findings.

Abstract P6-02-09: Hyperglycaemia and fibronectin: The criminal partnership during breast cancer progression

This abstract was withdrawn by the authors.

Hyperglycaemia-induced resistance to Docetaxel is negated by metformin: a role for IGFBP-2

The incidence of many common cancers varies between different populations and appears to be affected by a Western lifestyle. Highly proliferative malignant cells require sufficient levels of nutrients for their anabolic activity. Therefore, targeting genes and pathways involved in metabolic pathways could yield future therapeutics. A common pathway implicated in energetic and nutritional requirements of a cell is the LKB1/AMPK pathway. Metformin is a widely studied anti-diabetic drug, which improves glycaemia in patients with type 2 diabetes by targeting this pathway. We investigated the effect of metformin on prostate cancer cell lines and evaluated its mechanism of action using DU145, LNCaP, PC3 and VCaP prostate cancer cell lines. Trypan blue dye-exclusion assay was used to assess levels of cell death. Western immunoblotting was used to determine the abundance of proteins. Insulin-like growth factor-binding protein-2 (IGFBP-2) and AMPK genes were silenced using siRNA. Effects on cell morphology were visualised using microscopy. IGFBP-2 gene expression was assessed using real-time RT-PCR. With DU145 and LNCaP cells metformin alone induced cell death, but this was reduced in hyperglycaemic conditions. Hyperglycaemia also reduced the sensitivity to Docetaxel, but this was countered by co-treatment with metformin. LKB1 was required for the activation of AMPK but was not essential to mediate the induction of cell death. An alternative pathway by which metformin exerted its action was through downregulation of IGFBP-2 in DU145 and LNCaP cells, independently of AMPK. This finding could have important implications in relation to therapeutic strategies in prostate cancer patients presenting with diabetes.

Guidelines for the diagnosis, prevention and management of chemical- and radiation-induced cystitis

Objective

Haemorrhagic cystitis (HC) is a relatively common complication of chemotherapy and radiotherapy to the pelvic area, but can be a challenging condition to treat, particularly since there is currently a lack of UK-led guidelines available on how it should optimally be defined and managed.

Materials and methods

A comprehensive literature search was undertaken to evaluate the evidence for the diagnosis, prevention and management of cancer treatment-induced HC.

Results

Recommendations and a proposed management algorithm for the diagnosis, prevention and treatment of HC, as well as the management of intractable haematuria, have been developed based on the expert opinion of the multidisciplinary consensus panel following a comprehensive review of the available clinical data.

Conclusion

These guidelines are relevant and applicable to current clinical practice and will help clinicians optimally define and manage this potentially serious condition.

Falling bladder cancer incidence from 1990 to 2009 is not producing universal mortality improvements

Objective

The objective of this article is to obtain up-to-date epidemiological statistics of bladder cancer in England.

Methods

We collected incidence from the National Cancer Data Repository (NCDR), survival from the national Cancer Information System (CIS), ethnicity information from the Hospital Episode Statistics (HES), mortality and smoking rates from the Office for National Statistics (ONS).

Results

Incidence of bladder cancer has fallen continuously. Mortality has reduced less, leading to worsening survival. Bladder cancer mainly affects men, the most deprived, and the elderly. The gender gap is decreasing, and the deprivation gap is unchanged. Mortality is unchanged in the youngest, oldest and least deprived females. Mortality has recently increased in the oldest males. The highest incidence and mortality is found in industrial areas. This study is limited by i) its retrospective design using existing databases, allowing identification of associations and statistical differences, but not causation; and ii) very restricted ethnicity data.

onclusion

Reductions in bladder cancer incidence and mortality in England coincide with a decrease in high-risk occupations and public health measures to reduce smoking. Some risk factors in modern living may as yet be unidentified. It remains paramount to ensure equity of access and treatment regardless of gender, age, region and social deprivation to further improve mortality.

Hyperglycaemia-induced chemoresistance in breast cancer cells: role of the estrogen receptor

Breast cancer patients with diabetes respond less well to chemotherapy; in keeping with this we determined previously that hyperglycaemia-induced chemoresistance in estrogen receptor (ERα) positive breast cancer cells and showed that this was mediated by fatty acid synthase (FASN). More recent evidence suggests that the effect of metabolic syndrome and diabetes is not the same for all subtypes of breast cancer with inferior disease-free survival and worse overall survival only found in women with ERα positive breast cancer and not for other subtypes. Here we examined the impact of hyperglycaemia on ERα negative breast cancer cells and further investigated the mechanism underlying chemoresistance in ERα with a view to identifying strategies to alleviate hyperglycaemia-induced chemoresistance. We found that hyperglycaemia-induced chemoresistance was only observed in ERα breast cancer cells and was dependent upon the expression of ERα as chemoresistance was negated when the ERα was silenced. Hyperglycaemia-induced an increase in activation and nuclear localisation of the ERα that was downstream of FASN and dependent on the activation of MAPK. We found that fulvestrant successfully negated the hyperglycaemia-induced chemoresistance, whereas tamoxifen had no effect. In summary our data suggests that the ERα may be a predictive marker of poor response to chemotherapy in breast cancer patients with diabetes. It further indicates that anti-estrogens could be an effective adjuvant to chemotherapy in such patients and indicates the importance for the personalised management of breast cancer patients with diabetes highlighting the need for clinical trials of tailored chemotherapy for diabetic patients diagnosed with ERα positive breast cancers.

Knowledge and perception of off-label drug use amongst prescribing physicians in a tertiary care hospital

INTRODUCTION

Off-label drug use is commonly reported in various disciplines of medicine. Considering the lacunae of studies from prescribers in the Indian subcontinent, the present study was conducted to explore their awareness and views of off-label drug use.

METHODS

A validated questionnaire was administered to interns, junior residents and faculty members who were recruited in the present study of various medical and surgical departments of Subharti Medical College, Meerut, India, a tertiary care teaching hospital. Descriptive statistics was used for analyzing the data.

RESULTS

A total of 59/85 (69%) stated that they have used a drug in an off-label manner mainly [31/85 (36.5%)] related to indications. Nearly half of the study participants (41/85, 48.2%) considered prescribing an off-label drug illegal and only 25/85 (29.3%) participants felt that they had adequate knowledge regarding the use of drugs in off-label manner. Out of the total 70 participants who answered the question related to informing parents/relatives while prescribing an off label drug, only 39/70 (55.7%) answered affirmative. Out of the remaining 31/70 (44.3%) of participants who did not inform about prescribing an off label drug, 9/31 (29%) felt that it was illegal and more than two-third (24/31, 77%) felt their knowledge on off-label drug use was insufficient. Surprisingly, 74/82 (90.2%) participants felt that a drug approved to be used in adults cannot be used in children for the same indication despite not having any alternative in pediatric age group.

CONCLUSION

We found an inadequate knowledge regarding the off-label drug use amongst the prescribers in a tertiary care medical college hospital. Many of the physicians felt such use as illegal and do not inform the patient's relatives about such acts. Considering the legal issues, clearly there exists a need to patch up this lacuna in developing countries like India.

Assessment of the metastable electronic state approach as a microscopically self-consistent description for the nonlinear response of atoms

This Letter presents the first quantitative assessment of the recently proposed metastable electronic state approach (MESA) for calculation of the nonlinear optical response of noble gas atoms. Based on the single active electron potentials for several atomic species, Stark resonant states are used to extract the nonlinear polarization and ionization rates free of any additional fitting parameters. It is shown that even the simplest version of the method provides a viable, first-principle-based, and self-consistent alternative to the standard model commonly used for simulations in the field of extreme nonlinear optics.

Treatment patterns and clinical outcomes in patients with renal cell carcinoma in the UK: insights from the RECCORD registry

BACKGROUND

The aim of the RECCORD registry was to gather real-world UK data on the use of targeted therapies in renal cell carcinoma (RCC) and assess clinical outcomes. Here, demographic and outcome data are presented with the treatment patterns and demographic profile of patients on the registry.

PATIENTS AND METHODS

Patients were retrospectively identified at seven UK hospitals with large cancer centres in England (5), Scotland (1) and Wales (1). Anonymised data were collected through an online registry covering demographics, treatments and outcomes. Five hundred and fourteen UK adult patients with metastatic RCC were included in the study for analysis. Patients were included if they were treated for metastatic RCC at one of the seven centres, and started systemic anti-cancer treatment from March 2009 to November 2012 inclusive. In addition to demographic factors, the principal outcome measures were overall survival (OS), time to disease progression and toxicity.

RESULTS

The majority of first-line treatment was with sunitinib; first-line use of pazopanib increased as the study progressed. 15.8% of patients received second-line treatment, half of whom were prescribed everolimus. Median OS (from initiation of first-line treatment) was 23.9 months (95% confidence interval [CI] 18.6-29.1 months), similar to that reported for clinical trials of targeted RCC therapies [Ljungberg B, Campbell SC, Choi HY et al. The epidemiology of renal cell carcinoma. Eur Urol 2011; 60: 615-621; Abe H, Kamai T. Recent advances in the treatment of metastatic renal cell carcinoma. Int J Urol 2013; 20: 944-955; Motzer RJ, Hutson TE, Tomczak P et al. Overall survival and updated results for sunitinib compared with interferon alfa in patients with metastatic renal cell carcinoma. J Clin Oncol 2009; 27: 3584-3590]. OS was significantly longer for those who received second-line treatment after disease progression (33.0 months; 95% CI 30.8-35.2 months) than those who did not (20.9 months; 95% CI 16.4-25.3 months; P = 0.008).

CONCLUSIONS

RECCORD is a large 'real-world' database assessing metastatic RCC treatment patterns and outcomes. Treatment patterns changed over time as targeted therapies were approved and became widely available; survival data in RECCORD are consistent with those reported for systemic treatments in clinical trials. Kaplan-Meier analysis of results demonstrated that receiving second-line therapy was a major prognostic factor for longer OS.