ICORG 10-14: NEOadjuvant trial in Adenocarcinoma of the oEsophagus and oesophagoGastric junction International Study (Neo-AEGIS)

BACKGROUND

Neoadjuvant therapy is increasingly the standard of care in the management of locally advanced adenocarcinoma of the oesophagus and junction (AEG). In randomised controlled trials (RCTs), the MAGIC regimen of pre- and postoperative chemotherapy, and the CROSS regimen of preoperative chemotherapy combined with radiation, were superior to surgery only in RCTs that included AEG but were not powered on this cohort. No completed RCT has directly compared neoadjuvant or perioperative chemotherapy and neoadjuvant chemoradiation. The Neo-AEGIS trial, uniquely powered on AEG, and including comprehensive modern staging, compares both these regimens.

METHODS

This open label, multicentre, phase III RCT randomises patients (cT2-3, N0-3, M0) in a 1:1 fashion to receive CROSS protocol (Carboplatin and Paclitaxel with concurrent radiotherapy, 41.4Gy/23Fr, over 5 weeks). The power calculation is a 10% difference in favour of CROSS, powered at 80%, two-sided alpha level of 0.05, requiring 540 patients to be evaluable, 594 to be recruited if a 10% dropout is included (297 in each group). The primary endpoint is overall survival, with a minimum 3-year follow up. Secondary endpoints include: disease free survival, recurrence rates, clinical and pathological response rates, toxicities of induction regimens, post-operative pathology and tumour regression grade, operative in-hospital complications, and health-related quality of life. The trial also affords opportunities for establishing a bio-resource of pre-treatment and resected tumour, and translational research.

DISCUSSION

This RCT directly compares two established treatment regimens, and addresses whether radiation therapy positively impacts on overall survival compared with a standard perioperative chemotherapy regimen Sponsor: Irish Clinical Research Group (ICORG).

TRIAL REGISTRATION

NCT01726452 . Protocol 10-14. Date of registration 06/11/2012.

A case of polymicrobial anaerobic spondylodiscitis due to Parvimonas micra and Fusobacterium nucleatum

Introduction. Here, we present a case of polymicrobial anaerobic spondylodiscitis.

Case Presentation. A forty-five year-old female patient was referred to a specialist orthopaedic hospital with an eight week history of back pain without fevers. X-ray imaging and magnetic resonance imaging showed acute osteomyelitis of the twelfth thoracic and first lumbar vertebrae. Prolonged enrichment cultures grew Parvimonas micra and Fusobacterium nucleatum, identified by matrix-assisted laser desorption ionisation-time of flight (MALDI-ToF) mass spectrometry (MS). The patient was successfully treated with six weeks of intravenous ertapenem and oral clindamycin.

Conclusion. Anaerobic discitis is rare, and polymicrobial discitis is rarer still. A PubMed literature review revealed only seven cases of F. nucleatum discitis and only twelve cases of P. micra discitis; this includes only one other reported case of a polymicrobial discitis due to infection with both anaerobes. We emphasise the importance of prolonging enrichment culture and the use of fast yet accurate identification of anaerobes using MALDI-ToF MS in these infections.

Abstract PD5-06: Prognostic value of molecular tumor infiltrating lymphocyte (mTIL) signatures in HER2-positive breast cancer patients in N9831 and FinHer/FinXX trials

Background: While previous study showed that the enrichment of immune-related gene expression was associated with outcome in HER2+ patients receiving sequential or concurrent trastuzumab (H), stromal tumor infiltrating lymphocytes (sTIL) have not been consistently shown to associate with outcome in this group of patients. Given that TIL scoring may be subjective, we analyzed molecular signatures of different subsets of tumor infiltrating immune cell populations, using NanoStringTM gene expression data to assess molecular TIL (mTIL) signature enrichment and intrinsic subtype as a function of relapse-free survival (RFS).

Methods: NanoStringTM technology was used to quantify mRNA in samples from 1,280 patients in N9831, 168 patients in FinHer, and 170 patients in FinXX. In N9831, patients in arm A were treated with chemotherapy alone (AC-T), arm B received chemotherapy followed by sequential H (AC-T-H), and arm C received H concurrently with chemotherapy (AC-TH). In the FinHer trial, H was given concurrently for 9 weeks and either 1 year or 9 weeks in FinXX trial. Cox proportional hazard ratio (HR) was used to determine the association of each gene signature with RFS. Different immune subset signatures, including CD45, B-cells, CD8 T-cells, cytotoxic-cells, and T-cells were analyzed using algorithms developed by NanoString.

Results: In N9831, CD45, cytotoxic-cell, and T-cell signatures were significantly associated with improved RFS in patients receiving chemotherapy alone and AC-T-H. However, none of the mTIL signatures were significantly associated with outcome in patients receiving AC-TH. Patients lacking CD45 enrichment had better outcome when H was given concurrently with chemotherapy. The 10-year Kaplan-Meier estimates for RFS in arm B patients with CD45 enrichment or no enrichment were 81.3% and 72.6%, respectively (HR 0.63 [95% CI, 0.42-0.93]; p = 0.02), and in arm C were 83.6% and 79.8%, respectively (HR 0.79, 95%CI 0.49-1.28; p = 0.34). Among patients with HER2-enriched subtype, all of the mTIL signatures were associated with improved RFS in arm A (AC-T) and B (AC-T-H) but remained non-significant in arm C (AC-TH). In patients with luminal subtypes, mTIL signatures were not significantly associated with outcome in patients treated with chemotherapy alone. Similar findings were observed in the FinHer and FinXX trials, in which, none of mTIL signatures were significantly associated with outcome among patients who received H.

Conclusion: This analysis sheds light on previous discrepancy between immune-related gene signature and sTIL findings. Our data also suggests that the poor prognosis associated with lack of infiltrating immune cells can be partly overcome by the concomitant administration of H with chemotherapy. mTIL signatures, specifically CD45, cytoxic, and T cells, were prognostically associated with improved outcome in patients receiving chemotherapy without concurrent trastuzumab. Understanding the role of the immune system in response to H will require a higher degree of granularity than can be achieved by histological quantification of TILs. Further studies are needed to validate the significance of mTIL signatures as predictive or prognostic biomarker in HER+ patients.

Citation Format: Chumsri S, Serie DJ, Mashadi-Hossein A, Tenner KS, Lauttia SL, Moreno-Aspitia A, McLaughlin SA, Nassar A, Warren S, Danaher P, Colon-Otero G, Lindman H, Joensuu H, Perez EA, Thompson EA. Prognostic value of molecular tumor infiltrating lymphocyte (mTIL) signatures in HER2-positive breast cancer patients in N9831 and FinHer/FinXX trials [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD5-06.

Unwrapping 3D complex hollow organs for spatial dose surface analysis

PURPOSE

Toxicity dose-response models describe the correlation between dose delivered to an organ and a given toxic endpoint. Duodenal toxicity is a dose limiting factor in the treatment of pancreatic cancer with radiation but the relationship between dose and toxicity in the duodenum is not well understood. While there have been limited studies into duodenal toxicity through investigations of the volume of the organ receiving dose over a specific threshold, both dose-volume and dose-surface histograms lack spatial information about the dose distribution, which may be important in determining normal tissue response. Due to the complex geometry of the duodenum, previous methods for unwrapping tubular organs for spatial modeling of toxicity are insufficient. A geometrically robust method for producing 2D dose surface maps (DSMs), specifically for the duodenum, has been developed and tested in order to characterize the spatial dose distribution.

METHODS

The organ contour is defined using Delaunay triangulation. The user selects a start and end coordinate in the structure and a path is found by regulating both length and curvature. This path is discretized and rays are cast from each point on the plane normal to the vector between the previous and the next point on the path and the dose at the closest perimeter point recorded. These angular perimeter slices are "unwrapped" from the edge distal to the pancreas to ensure the high dose region (proximal to the tumor) falls in the centre of the dose map. Gamma analysis is used to quantify the robustness of this method and the effect of overlapping planes.

RESULTS

This method was used to extract DSMs for 15 duodena, with one esophagus case to illustrate the application to simpler geometries. Visual comparison indicates that a 30 × 30 map provides sufficient resolution to view gross spatial features of interest. A lookup table is created to store the area (cm2) represented by each pixel in the DSMs in order to allow spatial descriptors in absolute size. The method described in this paper is robust, requires minimal human interaction, has been shown to be generalizable to simpler geometries, and uses readily available commercial software. The difference seen in DSMs due to overlapping planes is large and justifies the need for a solution that removes such planes.

CONCLUSIONS

This is the first time 2D dose surface maps have been produced for the duodenum and provide spatial dose distribution information which can be explored to create models that may improve toxicity prediction in treatments for locally advanced pancreatic cancer.

^{7}Be(n,α)^{4}He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN

The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.

Qualitative analysis of mental health service users' reported experiences of discrimination

OBJECTIVE

To better understand mental health service users' experiences of stigma and discrimination in different settings.

METHOD

An annual telephone survey of people with a mental health diagnosis conducted to evaluate the Time to Change antistigma campaign in England. Of 985 people who participated in 2013, 84 took part in a qualitative interview which was audio recorded. Of these, 50 interviews were transcribed and thematically analysed to explore accounts of discrimination. We analysed common types of behaviour; motivations ascribed to the discriminators; expectations of what fair treatment would have been; and the impact of discrimination on participants.

RESULTS

Discrimination was most common in five contexts: welfare benefits, mental health care, physical health care, family and friends. Participants often found it hard to assess whether a behaviour was discriminatory or not. Lack of support, whether by public services or by friends and family, was often experienced as discrimination, reflecting an expectation that positive behaviours and reasonable adjustments should be offered in response to mental health needs.

CONCLUSION

The impact of discrimination across different settings was often perceived by participants as aggravating their mental health, and there is thus a need to treat discrimination as a health issue, not just a social justice issue.

Late Ebola virus relapse causing meningoencephalitis: a case report

BACKGROUND

There are thousands of survivors of the 2014 Ebola outbreak in west Africa. Ebola virus can persist in survivors for months in immune-privileged sites; however, viral relapse causing life-threatening and potentially transmissible disease has not been described. We report a case of late relapse in a patient who had been treated for severe Ebola virus disease with high viral load (peak cycle threshold value 13.2).

METHODS

A 39-year-old female nurse from Scotland, who had assisted the humanitarian effort in Sierra Leone, had received intensive supportive treatment and experimental antiviral therapies, and had been discharged with undetectable Ebola virus RNA in peripheral blood. The patient was readmitted to hospital 9 months after discharge with symptoms of acute meningitis, and was found to have Ebola virus in cerebrospinal fluid (CSF). She was treated with supportive therapy and experimental antiviral drug GS-5734 (Gilead Sciences, San Francisco, Foster City, CA, USA). We monitored Ebola virus RNA in CSF and plasma, and sequenced the viral genome using an unbiased metagenomic approach.

FINDINGS

On admission, reverse transcriptase PCR identified Ebola virus RNA at a higher level in CSF (cycle threshold value 23.7) than plasma (31.3); infectious virus was only recovered from CSF. The patient developed progressive meningoencephalitis with cranial neuropathies and radiculopathy. Clinical recovery was associated with addition of high-dose corticosteroids during GS-5734 treatment. CSF Ebola virus RNA slowly declined and was undetectable following 14 days of treatment with GS-5734. Sequencing of plasma and CSF viral genome revealed only two non-coding changes compared with the original infecting virus.

INTERPRETATION

Our report shows that previously unanticipated, late, severe relapses of Ebola virus can occur, in this case in the CNS. This finding fundamentally redefines what is known about the natural history of Ebola virus infection. Vigilance should be maintained in the thousands of Ebola survivors for cases of relapsed infection. The potential for these cases to initiate new transmission chains is a serious public health concern.

FUNDING

Royal Free London NHS Foundation Trust.

Thromboelastography in the Management of Coagulopathy Associated With Ebola Virus Disease

Here, we describe the first use of thromboelastography (TEG) in the management of 2 cases of Ebola virus disease. Early in their illness, both patients had evidence of a consumptive coagulopathy. As this resolved, TEG demonstrated that both developed a marked hypercoagulable state, which was treated with low-molecular-weight heparin.

Rosiglitazone treatment and cardiovascular disease in the Veterans Affairs Diabetes Trial

AIMS

To evaluate the relationship between patterns of rosiglitazone use and cardiovascular (CV) outcomes in the Veterans Affairs Diabetes Trial (VADT).

METHODS

Time-dependent survival analyses, case-control and 1 : 1 propensity matching approaches were used to examine the relationship between patterns of rosiglitazone use and CV outcomes in the VADT, a randomized controlled study that assessed the effect of intensive glycaemic control on CV outcomes in 1791 patients with type 2 diabetes (T2D) whose mean age was 60.4 ± 9 years. Participants were recruited between 1 December 2000 and 31 May 2003, and were followed for 5-7.5 years (median 5.6) with a final visit by 31 May 2008. Rosiglitazone (4 mg and 8 mg daily) was initiated per protocol in both the intensive-therapy and standard-therapy groups. Main outcomes included a composite CV outcome, CV death and myocardial infarction (MI).

RESULTS

Both daily doses of rosiglitazone were associated with lower risk for the primary composite CV outcome [4 mg: hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.49-0.81 and 8 mg: HR 0.60, 95% CI 0.49-0.75] after adjusting for demographic and clinical covariates. A reduction in CV death was also observed (HR 0.25, p < 0.001, for both 4 and 8 mg/day rosiglitazone); however, the effect on MI was less evident for 8 mg/day and not significant for 4 mg/day.

CONCLUSIONS

In older patients with T2D the use of rosiglitazone was associated with decreased risk of the primary CV composite outcome and CV death. Rosiglitazone use did not lead to a higher risk of MI.

Post-exposure prophylaxis against Ebola virus disease with experimental antiviral agents: a case-series of health-care workers

BACKGROUND

Although a few international health-care workers who have assisted in the current Ebola outbreak in west Africa have been medically evacuated for treatment of Ebola virus disease, more commonly they were evacuated after potential accidental exposure to Ebola virus. An urgent need exists for a consensus about the risk assessment of Ebola virus transmission after accidental exposure, and to investigate the use of post-exposure prophylaxis (PEP). Experimental vaccines have occasionally been used for Ebola PEP, but newly developed experimental antiviral agents have potential advantages. Here, we describe a new method for risk assessment and management of health-care workers potentially exposed to Ebola virus and report the use of experimental antiviral therapies for Ebola PEP in people.

METHODS

We devised a risk assessment and management algorithm for health-care workers potentially exposed to Ebola virus and applied this to eight consecutive individuals who were medically evacuated to the UK from west Africa between January, and March, 2015. PEP with antiviral agents was given to health-care workers assessed to have had substantial risk exposures to Ebola virus. Participants were followed up for 42 days after potential exposure.

FINDINGS

Four of eight health-care workers were classified as having had low risk exposures and managed by watchful waiting in the community. None of these health-care workers developed Ebola virus disease. The other four health-care workers had intermediate or maximum risk exposures and were given PEP with antiviral agents. PEP was well tolerated with no serious adverse effects. None of these four health-care workers, including two with maximum risk exposures from penetrating injuries with freshly used hollow-bore needles, developed Ebola virus disease.

INTERPRETATION

Standardised risk assessment should be adopted and consensus guidelines developed to systematically study the efficacy and safety of PEP with experimental agents. New experimental antiviral treatments are a viable option for PEP against Ebola.

FUNDING

Royal Free London NHS Foundation Trust.

Influence of blood flow occlusion on the development of peripheral and central fatigue during small muscle mass handgrip exercise

Critical power represents an important threshold for neuromuscular fatigue development and may, therefore, dictate intensities for which exercise tolerance is determined by the magnitude of fatigue accrued. Peripheral fatigue appears to be constant across O2 delivery conditions for large muscle mass exercise, but this consistency is equivocal for smaller muscle mass exercise. We sought to determine the influence of blood flow occlusion during handgrip exercise on neuromuscular fatigue development and to examine the relationship between neuromuscular fatigue development and W '. Blood flow occlusion influenced the development of both peripheral and central fatigue, thus providing further evidence that the magnitude of peripheral fatigue is not constant across O2 delivery conditions for small muscle mass exercise. W ' appears to be related to the magnitude of fatigue accrued during exercise, which may explain the reported consistency of intramuscular metabolic perturbations and work performed for severe-intensity exercise. The influence of the muscle metabolic milieu on peripheral and central fatigue is currently unclear. Moreover, the relationships between peripheral and central fatigue and the curvature constant (W ') have not been investigated. Six men (age: 25 ± 4 years, body mass: 82 ± 10 kg, height: 179 ± 4 cm) completed four constant power handgrip tests to exhaustion under conditions of control exercise (Con), blood flow occlusion exercise (Occ), Con with 5 min post-exercise blood flow occlusion (Con + Occ), and Occ with 5 min post-exercise blood flow occlusion (Occ + Occ). Neuromuscular fatigue measurements and W ' were obtained for each subject. Each trial resulted in significant peripheral and central fatigue. Significantly greater peripheral (79.7 ± 5.1% vs. 22.7 ± 6.0%) and central (42.6 ± 3.9% vs. 4.9 ± 2.0%) fatigue occurred for Occ than for Con. In addition, significantly greater peripheral (83.0 ± 4.2% vs. 69.0 ± 6.2%) and central (65.5 ± 14.6% vs. 18.6 ± 4.1%) fatigue occurred for Occ + Occ than for Con + Occ. W ' was significantly related to the magnitude of global (r = 0.91) and peripheral (r = 0.83) fatigue. The current findings demonstrate that blood flow occlusion exacerbated the development of both peripheral and central fatigue and that post-exercise blood flow occlusion prevented the recovery of both peripheral and central fatigue. Moreover, the current findings suggest that W ' may be determined by the magnitude of fatigue accrued during exercise.

A misdiagnosed melanoma: a case of cutaneous epithelioid malignant peripheral nerve sheath tumor

Malignant Peripheral Nerve Sheath Tumor (MPNST) is a rare soft tissue sarcoma that can occur in superficial locations. Histologically it is categorized into two variants: a conventional/spindled and an epithelioid variant. The latter one is very rare and can be confused histologically with malignant melanoma as it is diffusely positive for S100-protein. Herein we present a case that was initially misdiagnosed as malignant melanoma and discuss morphological and immunohistochemical clues to reach a correct diagnosis.

Structural insights into magnetic clusters grown inside virus capsids

Magnetic nanoparticles have multiple applications in materials science. In particular, virus capsids have been suggested as promising templates for building up nanometric-sized magnetic clusters by taking advantage of their inner cavity as a nanoreactor. In this study we investigate the magnetization of individual cobalt-filled cowpea mosaic virus empty virus-like particles using atomic force microscopy. We also combine the analysis of the effects of dehydration on the structure of virus particles with a comparison of their magnetic signal to that provided by commercially available magnetic nanoparticles of similar size. These two approaches allow the evaluation of the structure of the metallic cluster grown inside the virus capsid. We conclude that, rather than forming solid clusters, cobalt inside viruses forms a discontinuous structure that does not completely fill the virus cavity and reaches about 10% of its volume.

Performance of administrative case definitions for comorbidity in multiple sclerosis in Manitoba and Nova Scotia

Introduction

As the population ages and the prevalence of comorbid conditions increases, the need for feasible, validated methods of comorbidity surveillance in chronic diseases such as multiple sclerosis (MS) increases.

Methods

Using kappa (k) statistics, we evaluated the performance of administrative case definitions for comorbidities commonly observed in MS by comparing agreement between Manitoba (MB) administrative data and self-report (n = 606) and Nova Scotia (NS) administrative data and self-report (n = 1923).

Results

Agreement between the administrative definitions and self-report was substantial for hypertension (k = 0.69 [NS], 0.76 [MB]) and diabetes (k = 0.70 [NS], 0.66 [MB]); moderate for hyperlipidemia (k = 0.53 [NS], 0.51 [MB]) and heart disease (k = 0.42 [NS], 0.51 [MB]) and fair for anxiety (k = 0.27 [NS], 0.26 [MB]). In NS, agreement was substantial for inflammatory bowel disease (k = 0.71) and moderate for epilepsy (k = 0.48).

Conclusion

Administrative definitions for commonly observed comorbidities in MS performed well in 2 distinct jurisdictions. This suggests that they could be used more broadly across Canada and in national studies.

Performance of administrative case definitions for comorbidity in multiple sclerosis in Manitoba and Nova Scotia

INTRODUCTION

As the population ages and the prevalence of comorbid conditions increases, the need for feasible, validated methods of comorbidity surveillance in chronic diseases such as multiple sclerosis (MS) increases.

METHODS

Using kappa (k) statistics, we evaluated the performance of administrative case definitions for comorbidities commonly observed in MS by comparing agreement between Manitoba (MB) administrative data and self-report (n = 606) and Nova Scotia (NS) administrative data and self-report (n = 1923).

RESULTS

Agreement between the administrative definitions and self-report was substantial for hypertension (k = 0.69 [NS], 0.76 [MB]) and diabetes (k = 0.70 [NS], 0.66 [MB]); moderate for hyperlipidemia (k = 0.53 [NS], 0.51 [MB]) and heart disease (k = 0.42 [NS], 0.51 [MB]) and fair for anxiety (k = 0.27 [NS], 0.26 [MB]). In NS, agreement was substantial for inflammatory bowel disease (k = 0.71) and moderate for epilepsy (k = 0.48).

CONCLUSION

Administrative definitions for commonly observed comorbidities in MS performed well in 2 distinct jurisdictions. This suggests that they could be used more broadly across Canada and in national studies.

A prospective study of early removal of the urethral catheter after colorectal surgery in patients having epidural analgesia as part of the Enhanced Recovery After Surgery programme

AIM

Early removal of the urethral catheters is part of the enhanced postoperative recovery programme (ERAS). The effect of epidural anaesthesia on urinary retention was investigated in patients after colorectal resection.

METHOD

A prospective cohort study of all patients having colorectal surgery within an ERAS programme that included insertion of an epidural catheter over the last 5 years.

RESULTS

Two-hundred and ten patients had an epidural and a urethral catheter postoperatively. The duration of catheterization was not recorded in one patient who was therefore excluded from the study. One-hundred and eighteen patients had a trial without catheter (TWOC) prior to stopping the epidural (early TWOC). Ninety-one patients had TWOC after the epidural was stopped (late TWOC). Sixteen (7.6%) patients went into urinary retention (14 early TWOC and two late TWOC). The rate of urinary retention in the early TWOC group was significantly higher than that in the late TWOC group (11.9% vs 2.2%; χ(2), P = 0.009). Those who underwent a laparoscopic resection were significantly more likely to have undergone an early TWOC (χ(2), P = 0.001); however, there was no difference in retention rates between open and laparoscopic surgery (χ(2), P = 0.402). Pelvic surgery was not significantly associated with an increased risk of postoperative urinary retention (χ(2), P = 0.627). Male sex was not significantly associated with urinary retention (χ(2), P = 0.087). In the early TWOC group 86% had the catheter removed within 24 hours of surgery.

CONCLUSION

Early TWOC with epidural analgesia running significantly increases the risk of urinary retention; however, it was still successful in 88% of patients.

Comparison of four target volume definitions for pancreatic cancer. Guidelines for treatment of the lymphatics and the primary tumor

BACKGROUND AND PURPOSE

Target volume definitions for radiotherapy in pancreatic ductal adenocarcinoma (PDAC) vary substantially. Some groups aim to treat the primary tumor only, whereas others include elective lymph nodes (eLNs). eLNs close to the primary tumor are often included unintentionally within the treatment volume, depending on the respective treatment philosophies. We aimed to measure the percentages of anatomical coverage of eLNs by comparing four different contouring guidelines.

PATIENTS AND METHODS

Planning target volumes (PTVs) were contoured using planning computed tomography (CT) scans of 11 patients with PDAC based on the Oxford, RTOG (Radiation Therapy Oncology Group), Michigan, and SCALOP (Selective Chemoradiation in Advanced Localised Pancreatic Cancer trial) guidelines. Clinical target volumes (CTVs) included the peripancreatic, para-aortic, paracaval, celiac trunk, superior mesenteric, and portal vein lymph node areas. Volumetric comparisons of the coverage of all eLN regions were conducted to illustrate the differences between the four contouring strategies.

RESULTS

The PTV sizes of the RTOG and Oxford guidelines were comparable. The SCALOP and Michigan PTV sizes were similar to each other and significantly smaller than the RTOG and Oxford PTVs. A large variability of eLN coverage was found for the various subregions according to the respective contouring strategies.

CONCLUSION

This is the first study to directly compare the percentage of anatomical coverage of eLNs according to four PTVs in the same patient cohort. Potential practical consequences are discussed in detail.

Gametocyte carriage in Plasmodium falciparum-infected travellers

BACKGROUND

Gametocytes are the sexual stage of Plasmodium parasites. The determinants of gametocyte carriage have been studied extensively in endemic areas, but have rarely been explored in travellers with malaria. The incidence of gametocytaemia, and factors associated with gametocyte emergence in adult travellers with Plasmodium falciparum malaria was investigated at the Hospital for Tropical Diseases in London.

METHODS

Clinical, parasitological and demographic data for all patients presenting with P. falciparum malaria between January 2001 and December 2011 were extracted from a prospective database. These data were supplemented by manual searches of laboratory records and patient case notes.

RESULTS

Seven hundred and seventy three adult patients with laboratory-confirmed P. falciparum malaria were identified. Four hundred and sixty five (60%) were born in a country where malaria is endemic. Patients presented to hospital a median of four days into their illness. The median maximum parasite count was 0.4%. One hundred and ninety six patients (25%) had gametocytes; 94 (12%) on admission, and 102 (13%) developing during treatment. Gametocytaemia on admission was associated with anaemia and a lower maximum parasitaemia. Patients with gametocytes at presentation were less likely to have thrombocytopenia or severe malaria. Patients who developed gametocytes during treatment were more likely to have had parasitaemia of long duration, a high maximum parasitaemia and to have had severe malaria. There was no apparent association between the appearance of gametocytes and treatment regimen.

CONCLUSIONS

The development of gametocytaemia in travellers with P. falciparum is associated with factors similar to those reported among populations in endemic areas. These data suggest that acquired immunity to malaria is not the only determinant of patterns of gametocyte carriage among patients with the disease.