Strangulated Inguinal Hernia Complicated With Double Hydrocele and Retention of Urine.

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Molecular radiotheranostics for neuroendocrine tumours

This article discusses the important role of nuclear medicine imaging and therapy in the management of neuroendocrine tumours (NETs). Somatostatin receptor scintigraphy has a high impact on patient management versus conventional imaging. Molecular radiotherapy is an important part of the management of patients with NETs. Selection of patients for molecular radiotherapy in NETs is based on uptake on their radionuclide imaging study. The imaging agent has the same mechanism of uptake as the therapeutic agent. Thus, the imaging study preselects patients that are likely to concentrate radiation within their tumours

FDG–PET in the prediction of survival of patients with cancer of the pancreas: a pilot study

Carcinoma of the pancreas is an aggressive tumour with an extremely poor prognosis. Recent studies have shown that chemotherapy can improve survival as well as quality of life. Since the prognosis is generally poor, the identification of early responders to chemotherapy is important to avoid unnecessary toxicity in patients who are not responding. Response assessment by conventional radiographic methods is problematical because treatment induces fibrosis and makes tumour measurements difficult. The aim of this pilot study was to assess 18-fluoro-deoxy-glucose positron emission tomography (FDG-PET) as an early marker of the benefit of chemotherapy. Eleven patients with histologically proven adenocarcinoma of the pancreas were treated with protracted venous infusional 5-fluorouracil (PVI 5-FU) alone or PVI 5-FU and mitomycin C (MMC). FDG-PET scans were performed prior to and at 1 month following the commencement of chemotherapy. FDG uptake was compared with the tumour dimensions measured on a computer tomographic (CT) scan. Patients were followed up for relapse, death and symptomatic response. Three of the 11 patients had no measurable FDG uptake prior to chemotherapy. Of the eight patients who had measurable uptake prior to treatment, seven had a reduction in uptake at 1 month. Six out of the 11 patients had no measurable FDG uptake at 1 month. The overall survival (OS) in these patients ranged from 124 to 1460 days, with a median of 318.5 days. This was superior in comparison to patients who had residual FDG uptake at 1 month (median survival 318.5 days vs 139 days;P = 0.034) and there was a trend to improved symptoms (84% [5/6] vs 20% [1/5];P = 0.13). There was no statistically significant correlation between best CT response and FDG uptake at 1 month. These results suggest that the absence of FDG uptake at 1 month following chemotherapy for carcinoma of the pancreas is an indicator of improved overall survival. This suggests that FDG-PET may be superior to response assessment by conventional radiographic methods and FDG-PET may have the potential to help make difficult treatment decisions in the management of pancreatic cancer. Larger prospective studies are required to confirm this finding. © 2000 Cancer Research Campaig

Investigating the potential clinical benefit of Selumetinib in resensitising advanced iodine refractory differentiated thyroid cancer to radioiodine therapy (SEL-I-METRY): protocol for a multicentre UK single arm phase II trial

Background Thyroid cancer is the most common endocrine malignancy. Some advanced disease is, or becomes, resistant to radioactive iodine therapy (refractory disease); this holds poor prognosis of 10% 10-year overall survival. Whilst Sorafenib and Lenvatinib are now licenced for the treatment of progressive iodine refractory thyroid cancer, these treatments require continuing treatment and can be associated with significant toxicity. Evidence from a pilot study has demonstrated feasibility of Selumetinib to allow the reintroduction of I-131 therapy; this larger, multicentre study is required to demonstrate the broader clinical impact of this approach before progression to a confirmatory trial. Methods SEL-I-METRY is a UK, single-arm, multi-centre, two-stage phase II trial. Participants with locally advanced or metastatic differentiated thyroid cancer with at least one measureable lesion and iodine refractory disease will be recruited from 8 NHS Hospitals and treated with 4-weeks of oral Selumetinib and assessed for sufficient I-123 uptake (defined as any uptake in a lesion with no previous uptake or 30% or greater increase in uptake). Those with sufficient uptake will be treated with I-131 and followed for clinical outcomes. Radiation absorbed doses will be predicted from I-123 SPECT/CT and verified from scans following the therapy. 60 patients will be recruited to assess the primary objective of whether the treatment schedule leads to increased progression-free survival compared to historical control data. Discussion The SEL-I-METRY trial will investigate the effect of Selumetinib followed by I-131 therapy on progression-free survival in radioiodine refractory patients with differentiated thyroid cancer showing increased radioiodine uptake following initial treatment with Selumetinib. In addition, information on toxicity and dosimetry will be collected. This study presents an unprecedented opportunity to investigate the role of lesional dosimetry in molecular radiotherapy, leading to greater personalisation of therapy. To date this has been a neglected area of research. The findings of this trial will be useful to healthcare professionals and patients alike to determine whether further study of this agent is warranted. It is hoped that the development of the infrastructure to deliver a multicentre trial involving molecular radiotherapy dosimetry will lead to further trials in this field. Trial registration SEL-I-METRY is registered under ISRCTN17468602, 02/12/2015

The Scherk-Schwarz mechanism as a flux compactification with internal torsion

The aim of this paper is to make progress in the understanding of the Scherk-Schwarz dimensional reduction in terms of a compactification in the presence of background fluxes and torsion. From the eleven dimensional supergravity point of view, we find that a general E6(6) S-S phase may be obtained by turning on an appropriate background torsion, together with suitable fluxes, some of which can be directly identified with certain components of the four-form field-strength. Furthermore, we introduce a novel (four dimensional) approach to the study of dualities between flux/torsion compactifications of Type II/M-theory. This approach defines the action that duality should have on the background quantities, in order for the E7(7) invariance of the field equations and Bianchi identities to be restored also in the presence of fluxes/torsion. This analysis further implies the interpretation of the torsion flux as the T-dual of the NS three-form flux.Comment: Version published on J. High Energy Phy

EANM practical guidance on uncertainty analysis for molecular radiotherapy absorbed dose calculations.

A framework is proposed for modelling the uncertainty in the measurement processes constituting the dosimetry chain that are involved in internal absorbed dose calculations. The starting point is the basic model for absorbed dose in a site of interest as the product of the cumulated activity and a dose factor. In turn, the cumulated activity is given by the area under a time-activity curve derived from a time sequence of activity values. Each activity value is obtained in terms of a count rate, a calibration factor and a recovery coefficient (a correction for partial volume effects). The method to determine the recovery coefficient and the dose factor, both of which are dependent on the size of the volume of interest (VOI), are described. Consideration is given to propagating estimates of the quantities concerned and their associated uncertainties through the dosimetry chain to obtain an estimate of mean absorbed dose in the VOI and its associated uncertainty. This approach is demonstrated in a clinical example