The role of Fluorine-18-Fluorodeoxyglucose positron emission tomography in staging and restaging of patients with osteosarcoma

Background

The objective of this study is to systematically review the role of positron emission tomography (PET) and PET/computed tomography (PET/CT) with Fluorine-18-Fluorodeoxyglucose (FDG) in patients with osteosarcoma (OS).

Methods

A comprehensive literature search of published studies through October 10^th, 2012 in PubMed/MEDLINE, Embase and Scopus databases regarding whole-body FDG-PET and FDG-PET/CT in patients with OS was performed.

Results

We identified 13 studies including 289 patients with OS. With regard to the staging and restaging of OS, the diagnostic performance of FDG-PET and PET/CT seem to be high; FDG-PET and PET/CT seem to be superior to bone scintigraphy and conventional imaging methods in detecting bone metastases; conversely, spiral CT seems to be superior to FDG-PET in detecting pulmonary metastases from OS

Conclusions

Metabolic imaging may provide additional information in the evaluation of OS patients. The combination of FDG-PET or FDG-PET/CT with conventional imaging methods seems to be a valuable tool in the staging and restaging of OS and may have a relevant impact on the treatment planning.     

Value of adenosine deaminase (ADA) in ascitic fluid for the diagnosis of tuberculous peritonitis: a meta-analysis

BACKGROUND AND GOALS: Adenosine deaminase (ADA) levels are used for diagnosing tuberculosis in several locations and although many studies have evaluated ADA levels in ascitic fluid. These studies have defined arbitrary cut-off points creating difficulties in the clinical application of the results. The goals of this study are: to determine the usefulness of ADA levels in ascitic fluid as a diagnostic test for peritoneal tuberculosis (PTB) and define the best cut-off point. STUDY: A systematic review was done on the basis of 2 independent searches. We selected prospective studies that included consecutive patients. Diagnosis of PTB had to be confirmed by bacteriologic or histologic methods and ADA levels determined by the Giusti method. Inclusion/exclusion criteria were applied by 2 independent reviewers. A receiver operating characteristic curve was constructed to establish the optimal cut-off point and the likelihood ratios (LRs) estimated using fixed-effect pooled method. RESULTS: Twelve prospective studies were found. Four of them met the inclusion criteria and were thus included in the meta-analysis. They included 264 patients, of which 50 (18.9%) had PTB. ADA levels showed high sensitivity (100%) and specificity (97%) using cut-off values from 36 to 40 IU/L. The included studies were homogeneous. Optimal cut-off point was determined at 39 IU/L, and LRs were 26.8 and 0.038 for values above and below this cut-off. CONCLUSIONS: This study supports the proposition that ADA determination is a fast and discriminating test for diagnosing PTB with an optimal cut-off value of 39 IU/L.     

Insertional anatomy of peroneal brevis and longus tendon — A cadaveric study

BackgroundPeroneal Tendon (PT) complex is formed by the Peroneus Longus Tendon (PLT) and Peroneus Brevis Tendon (PBT), their synovial sheath, the superior and inferior retinaculum, and the Os Peroneum (OP). Their insertion is associated with some anatomic variability. Knowing these variants helps to understand the PT pathology and it may support the decision-making concerning the operative approach. The purpose of this study was to assess anatomical variability in PT insertion.MethodsTwenty fresh-frozen cadaveric feet were used. The lateral part of the ankle, foot and sole were dissected to expose PLT and PBT course and distal insertions.ResultsConcerning the PBT, eleven feet had a normal insertion in the base of the fifth metatarsal; the other nine had a variability. Regarding the PLT, thirteen out of twenty had the normal insertion in the first metatarsal; the remaining seven had anatomical variants.ConclusionsIn this study, we found a great variability in the insertional anatomy of PBT and PLT.Clinical relevanceIt is important that orthopedic surgeons are aware of the great variability of PT anatomical insertion when performing foot and ankle surgery, in order to avoid possible complications, for instance a PLT injury during preparation of tarso-metatarsal arthrodeses.     

Blood oxidative stress markers and Plasmodium falciparum malaria in non‐immune African children

Converging in vitro evidence and clinical data indicate that oxidative stress may play important roles in Plasmodium falciparum malaria, notably in the pathogenesis of severe anaemia. However, oxidative modifications of the red blood cell (RBC)‐membrane by 4‐hydroxynonenal (4‐HNE) and haemoglobin‐binding, previously hypothesized to contribute mechanistically to the pathogenesis of clinical malaria, have not yet been tested for clinical significance. In 349 non‐immune Mozambican newborns recruited in a double‐blind placebo‐controlled chemoprophylaxis trial, oxidative markers including 4‐HNE‐conjugates and membrane‐bound haemoglobin were longitudinally assessed from 2·5 to 24 months of age, at first acute malaria episode and in convalescence. During acute malaria, 4‐HNE‐conjugates were shown to increase significantly in parasitized and non‐parasitized RBCs. In parallel, advanced oxidation protein products (AOPP) rose in plasma. 4‐HNE‐conjugates correlated with AOPP and established plasma but not with RBC oxidative markers. High individual levels of 4‐HNE‐conjugates were predictive for increased malaria incidence rates in children until 2 years of life and elevated 4‐HNE‐conjugates in convalescence accompanied sustained anaemia after a malaria episode, indicating 4‐HNE‐conjugates as a novel patho‐mechanistic factor in malaria. A second oxidative marker, haemoglobin binding to RBC‐membranes, hypothesized to induce clearing of RBCs from circulation, was predictive for lower malaria incidence rates. Further studies will show whether or not higher membrane‐haemoglobin values at the first malaria episode may provide protection against malaria.     

Towards an RTS,S-based, multi-stage, multi-antigen vaccine against falciparum malaria: progress at the Walter Reed Army Institute of Research

The goal of the Malaria Vaccine Program at the Walter Reed Army Institute of Research (WRAIR) is to develop a licensed multi-antigen, multi-stage vaccine against Plasmodium falciparum able to prevent all symptomatic manifestations of malaria by preventing parasitemia. A secondary goal is to limit disease in vaccinees that do develop malaria. Malaria prevention will be achieved by inducing humoral and cellular immunity against the pre-erythrocytic circumsporozoite protein (CSP) and the liver stage antigen-1 (LSA-1). The strategy to limit disease will target immune responses against one or more blood stage antigens, merozoite surface protein-1 (MSP-1) and apical merozoite antigen-1 (AMA-1). The induction of T- and B-cell memory to achieve a sustained vaccine response may additionally require immunization with an adenovirus vector such as adenovirus serotype 35. RTS,S, a CSP-derived antigen developed by GlaxoSmithKline Biologicals in collaboration with the Walter Reed Army Institute of Research over the past 17 years, is the cornerstone of our program. RTS,S formulated in AS02A (a GSK proprietary formulation) is the only vaccine candidate shown in field trials to prevent malaria and, in one instance, to limit disease severity. Our vaccine development plan requires proof of an individual antigen's efficacy in a Phase 2 laboratory challenge or field trial prior to its integration into an RTS,S-based, multi-antigen vaccine. Progress has been accelerated through extensive partnerships with industrial, academic, governmental, and non-governmental organizations. Recent safety, immunogenicity, and efficacy trials in the US and Africa are presented, as well as plans for the development of a multi-antigen vaccine.