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Sonny Cher

Party All You Want After Work - 1 views

My current job ends at 10 in the evening. However, it is my friend's homecoming party and he invited me to come by after work. I knew I would definitely feel exhausted after work and I am afraid I ...

stimulants

started by Sonny Cher on 17 May 11 no follow-up yet
Sonny Cher

Party All You Want After Work - 1 views

My current job ends at 10 in the evening. However, it is my friend's homecoming party and he invited me to come by after work. I knew I would definitely feel exhausted after work and I am afraid I ...

stimulants

started by Sonny Cher on 20 Apr 11 no follow-up yet
Nathan Goodyear

25-Hydroxyvitamin D, 1,25-Dihydroxyvitamin D and Postoperative Outcome in Cardiac Surgery: The Journal of Clinical Endocrinology & Metabolism: Vol 100, No 1 - 0 views

press.endocrine.org/...jc.2014-3013

vitamin D CVD cardiovascular disease heart health cerebrovascular CVA surgery

shared by Nathan Goodyear on 14 Jan 15 - No Cached
  • Nathan Goodyear on 14 Jan 15
     
    low vitamin D predicts increased risk of Major adverse cardiac and/or cerebrovascular events after cardiac surgery.  The definition of low D was <30.  A better study would have been to stratify by 10s the risk.
Nathan Goodyear

http://press.endocrine.org/doi/pdf/10.1210/jc.2014-3818 - 0 views

press.endocrine.org/...jc.2014-3818

low T low Testosterone ED Estradiol SHBG erectile dysfunction libido men male hormone hormones

shared by Nathan Goodyear on 27 Jan 15 - No Cached
  • Nathan Goodyear on 27 Jan 15
     
    Study finds that low free T and low Total T were associated with decline in desire, ED and activity versus none with Estradiol and SHBG in older men.  The difficult issue is the threshold of "low T".  The definition of "low T" is not uniform and varies with age.  Thus baseline evaluations and correlation with symptoms, metabolic dysfunction must be done.
Nathan Goodyear

https://www.jstage.jst.go.jp/article/jcbn/58/1/58_15-48/_pdf - 0 views

www.jstage.jst.go.jp/..._pdf

lifestyle Testosterone low T low Testosterone exercise nutrition hormones obesity overweight

shared by Nathan Goodyear on 25 Jan 16 - No Cached
  • Nathan Goodyear on 25 Jan 16
     
    study finds that lifestyle interventions, aerobic exercise and calorie restriction, increased Testosterone levels in men that were overweight or obese.  The men included in this study did not meet most definitions of "low Testosterone".
Nathan Goodyear

Medical education in pharmacogenomics-results from a survey on pharmacogenetic knowledge in healthcare professionals within the European pharmacogenomics clinical implementation project Ubiquitous Pharmacogenomics (U-PGx) - 0 views

www.ncbi.nlm.nih.gov/...PMC5599468

genetics pharmacogenetics

shared by Nathan Goodyear on 17 Jan 18 - No Cached
  • Of participants, 84.3% found pharmacogenomics relevant to their current practice
  • More than two-thirds (65.7%) did not order nor recommend a pharmacogenomic test in the past year
  • pharmacogenomic testing was understood mainly for assessment of the variability of genes affecting drug disposition, metabolism and drug transport leading to individual responses to drugs
  • ...4 more annotations...
  • Pre-emptive, prospective, genotyping to make individualised drug therapy feasible is seen to contribute to personalised medicine
  • assumed to improve drug efficacy and safety
  • Potential benefits of pharmacogenomics (PGx) have been defined such as predicting intended response to medication by more accurate dosing, avoiding adverse drug reactions and therefore enhancing drug safety and reducing health care cost
  • survey among Dutch pharmacists revealed 14.7% recent users of PGx diagnostics [27], whereas in our cohort, the percentage was with 34.3% higher.
  • Nathan Goodyear on 17 Jan 18
     
    Doctors and pharmacists are slow to integrate pharmacogenetics. Good working definition of pharmacogenetics as well.
cityxrayclinic

CT Angiography in Delhi - Coronary Angiography in Delhi - 0 views

www.cityxrayclinic.com/...ct-angiography

Coronary Angiography in Delhi CT

shared by cityxrayclinic on 07 Jun 17 - No Cached
  • cityxrayclinic on 07 Jun 17
     
    CT Angiography or CTA stands for "Computed Tomography Angiography". It is a computed tomography technique which is mainly used to study the arteries and veins of the body. City x-ray and Scan Clinic (P) Ltd is one of the best diagnostic center in Delhi, which offers best CT Angiography facilities. You can book a test and get the reports online. Here you will have Somatom Definition AS 194 slice/sec most advanced Multi Slice Spiral CT Scanner from Siemens.
Rachel Renner

Superb Anti-Snoring Device - 1 views

Noiselezz is the best anti-snoring device that I have ever tried. My wife was about to kick me out of our bedroom until I have found KVG Australia's anti-snoring product. Honestly, I have already t...

started by Rachel Renner on 15 Oct 12 no follow-up yet
Nathan Goodyear

Metabolic effects of testosterone replacement therapy on hypogonadal men with type 2 diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials Cai X, Tian Y, Wu T, Cao CX, Li H, Wang KJ - Asian J Androl - 0 views

www.ajandrology.com/article.asp

Testosterone therapy diabetes lipids glucose triglycerides men male hormone hormones

shared by Nathan Goodyear on 17 Jan 14 - No Cached
  • up to 40% of men with T2DM have testosterone deficiency
  • Among diabetic patients, a reduction in sex hormone binding globulin levels induced by insulin resistance leads to a further decline of testosterone levels
  • low bioavailable testosterone concentration was related to decreased lean body mass and muscle strength
  • ...13 more annotations...
  • Testosterone deficiency has a high prevalence in men with T2DM, and it is also associated with impaired insulin sensitivity, increased percentage body fat, central obesity, dyslipidemia, hypertension and cardiovascular diseases (CVD)
  • A meta-analysis of four randomized controlled trials (RCTs) showed that TRT seemed to improve glycemic control as well as fat mass in T2DM subjects with low testosterone levels and sexual dysfunction.
  • testosterone administration could increase muscle mass and strength
  • Insulin stimulates glucose uptake into muscle and adipose tissue via the Glut4 glucose transporter isoform. When insulin activates signaling via the insulin receptor, Glut4 interacts with insulin receptor substrate 1 to initialize intracellular signaling and facilitate glucose transportation into the cell
  • The benefits of TRT on glucose metabolism can mainly be explained by its influence on the insulin signaling pathway
  • Insulin resistance as assessed by, which is calculated from the equation (If*Gf/22.5, where If is fasting insulin and Gf is fasting glucose), was definitely improved by TRT after testosterone administration in three studies
  • Testosterone was observed to elevate the expression levels and stimulate translocation of Glut4 in cultured skeletal muscle cells and to upregulate Glut4 by activating insulin receptor signaling pathways in neonatal rats
  • These effects were inhibited by a dihydrotestosterone (DHT) blocker, indicating that glucose uptake may correlate with conversion of testosterone to DHT and activation of the androgen receptor.
  • TRT reduced triglyceride levels
  • TRT has been reported to have a positive effect in the decrease of total and LDL cholesterol levels and triglycerides in hypogonadal men
  • a recent meta-analysis showed that statins could significantly lower testosterone concentrations.
  • Epidemiological studies have found a negative relationship between testosterone levels and typical cardiovascular risk markers, such as body mass index, waist circumference, visceral adiposity and carotid intima-media thickness.
  • Testosterone treatment was shown to raise hemoglobin, hematocrit and thromboxane, all of which might give rise to CVD
  • Nathan Goodyear on 17 Jan 14
     
    Low Testosterone is a very significant problem in men with type II Diabetes.  Estimated to reach 40%, likely much higher.  They based these estimates only on T levels and sexual symptoms. Testosterone improves glycemic control primarily through Increased transcription and transloction of GLUT4 insulin receptors to the cell surface.  Inflammation reduction is also a mechanism.  Testosteorne lowers Triglycerides in the traditional lipid profile.  Studies are mixed on the other aspects of  lipids.  
Amelie warner

High Quality & Authentic, Weight Loss Green Tea - 0 views

www.haocha.co.uk

Green tea Tea Formosa Ruby Tea

shared by Amelie warner on 30 Jan 14 - No Cached
  • Amelie warner on 30 Jan 14
     
    We travel thousands of miles each year, to find and select definitive examples of Asia's finest teas. To help you enjoy the best possible experience... #haocha http://bit.ly/LsZ2sO
Nathan Goodyear

Testosterone deficiency syndrome and cardiovascular health: An assessment of beliefs, knowledge and practice patterns of general practitioners and cardiologists in Victoria, BC - 0 views

www.ncbi.nlm.nih.gov/...PMC3929476

low T Testosterone cardiovascular disease physicians men male hormone hormones

shared by Nathan Goodyear on 03 Mar 14 - No Cached
  • The vast majority (88%) did not screen cardiac patients for TDS.
  • Testosterone deficiency has a prevalence of 7% in the general population, rising to 20% in elderly males
  • Males with CAD have lower testosterone levels than those with normal coronary angiograms of the same age,5 suggesting that the prevalence of testosterone deficiency is much higher in the CAD population
  • ...14 more annotations...
  • Men with hypertension, another established risk factor for CAD, have lower testosterone compared to normotensive men
  • Recent meta-analyses showed that testosterone levels are generally lower among patients with metabolic syndrome, regardless of the various definitions of metabolic syndrome that are used
  • Testosterone (total and bioavailable) and sex-hormone binding globulin (SHBG) are inversely associated with the prevalence of metabolic syndrome in men between the ages of 40 and 80, and this association persists across racial and ethnic backgrounds
  • ower levels of testosterone and SHBG predict a higher incidence of metabolic syndrome.
  • Low testosterone levels have been related to increased insulin resistance and cardiovascular mortality,12 even in the absence of overt type 2 diabetes mellitus.
  • testosterone levels (total and bioavailable) in middle-aged men are inversely correlated with insulin resistance
  • The Massachusetts Male Aging Study (MMAS) demonstrated that low levels of testosterone and SHBG are independent risk factors for the development of type 2 diabetes,
  • Andropausal men (age 58 ± 7 years) have a higher maximal carotid artery intima-media thickness
  • There is an inverse linear correlation between body mass index (BMI) and wait-to-hip ratio with testosterone and insulin-like growth factor-1 levels.
  • Testosterone supplementation for 1 year in hypogonadal men has been shown to cause a significant improvement in body weight, BMI, waist size, lipid profile, and C-reactive protein levels
  • TRT for 3 months in hypogonadal men with type 2 diabetes significantly improved fasting insulin sensitivity, fasting blood glucose and glycated hemoglobin.
  • Testosterone replacement can improve angina symptoms and delay the onset of cardiac ischemia, likely through a coronary vasodilator mechanism
  • ADT is associated with an increased risk of cardiovascular events, including myocardial infarction and cardiovascular mortality.
  • ADT significantly increases fat mass, decreases lean body mass,29,30 increases fasting plasma insulin and decreases insulin sensitivity31 and increases serum cholesterol and triglyceride levels
  • Nathan Goodyear on 03 Mar 14
     
    Startling study on the knowledge of Testosterone and cardiovascular disease in general practitioners and cardiologists in Canada.  Eight-eight percent did not screen patients with cardiovascular disease for low Testosterone.  A whopping 67% of physicians did not know that low T was a risk factor for cardiovascular disease, yet 62% believed Testosterone would increase exercise tolerance. The lack of knowledge displayed by physicians today is staggering and is an indictment of the governing bodies.  This was a survey conducted in Canada so there are obvious limitations to the strength/conclusion of this study.
Nathan Goodyear

Nutrition & Metabolism | Full text | Fructose, insulin resistance, and metabolic dyslipidemia - 0 views

www.nutritionandmetabolism.com/...5

fructose metabolic syndrome metabolic syndrome insulin resistance obesity nutrition metabolism

shared by Nathan Goodyear on 16 Sep 13 - Cached
  • For thousands of years humans consumed fructose amounting to 16–20 grams per day
  • daily consumptions amounting to 85–100 grams of fructose per day
  • Of key importance is the ability of fructose to by-pass the main regulatory step of glycolysis, the conversion of glucose-6-phosphate to fructose 1,6-bisphosphate, controlled by phosphofructokinase
  • ...29 more annotations...
  • Thus, while glucose metabolism is negatively regulated by phosphofructokinase, fructose can continuously enter the glycolytic pathway. Therefore, fructose can uncontrollably produce glucose, glycogen, lactate, and pyruvate, providing both the glycerol and acyl portions of acyl-glycerol molecules. These particular substrates, and the resultant excess energy flux due to unregulated fructose metabolism, will promote the over-production of TG (reviewed in [53]).
  • Glycemic excursions and insulin responses were reduced by 66% and 65%, respectively, in the fructose-consuming subjects
  • reduction in circulating leptin both in the short and long-term as well as a 30% reduction in ghrelin (an orexigenic gastroenteric hormone) in the fructose group compared to the glucose group.
  • A prolonged elevation of TG was also seen in the high fructose subjects
  • Both fat and fructose consumption usually results in low leptin concentrations which, in turn, leads to overeating in populations consuming energy from these particular macronutrients
  • Chronic fructose consumption reduces adiponectin responses, contributing to insulin resistance
  • A definite relationship has also been found between metabolic syndrome and hyperhomocysteinemia
  • the liver takes up dietary fructose rapidly where it can be converted to glycerol-3-phosphate. This substrate favours esterification of unbound FFA to form the TG
  • Fructose stimulates TG production, but impairs removal, creating the known dyslipidemic profile
  • the effects of fructose in promoting TG synthesis are independent of insulinemia
  • Although fructose does not appear to acutely increase insulin levels, chronic exposure seems to indirectly cause hyperinsulinemia and obesity through other mechanisms. One proposed mechanism involves GLUT5
  • If FFA are not removed from tissues, as occurs in fructose fed insulin resistant models, there is an increased energy and FFA flux that leads to the increased secretion of TG
  • In these scenarios, where there is excess hepatic fatty acid uptake, synthesis and secretion, 'input' of fats in the liver exceed 'outputs', and hepatic steatosis occurs
  • Carbohydrate induced hypertriglycerolemia results from a combination of both TG overproduction, and inadequate TG clearance
  • fructose-induced metabolic dyslipidemia is usually accompanied by whole body insulin resistance [100] and reduced hepatic insulin sensitivity
  • Excess VLDL secretion has been shown to deliver increased fatty acids and TG to muscle and other tissues, further inducing insulin resistance
  • the metabolic effects of fructose occur through rapid utilization in the liver due to the bypassing of the regulatory phosphofructokinase step in glycolysis. This in turn causes activation of pyruvate dehydrogenase, and subsequent modifications favoring esterification of fatty acids, again leading to increased VLDL secretion
  • High fructose diets can have a hypertriglyceridemic and pro-oxidant effect
  • Oxidative stress has often been implicated in the pathology of insulin resistance induced by fructose feeding
  • Administration of alpha-lipoic acid (LA) has been shown to prevent these changes, and improve insulin sensitivity
  • LA treatment also prevents several deleterious effects of fructose feeding: the increases in cholesterol, TG, activity of lipogenic enzymes, and VLDL secretion
  • Fructose has also been implicated in reducing PPARα levels
  • PPARα is a ligand activated nuclear hormone receptor that is responsible for inducing mitochondrial and peroxisomal β-oxidation
  • decreased PPARα expression can result in reduced oxidation, leading to cellular lipid accumulation
  • fructose diets altered the structure and function of VLDL particles causing and increase in the TG: protein ratio
  • LDL particle size has been found to be inversely related to TG concentration
  • therefore the higher TG results in a smaller, denser, more atherogenic LDL particle, which contributes to the morbidity of the metabolic disorders associated with insulin resistance
  • High fructose, which stimulates VLDL secretion, may initiate the cycle that results in metabolic syndrome long before type 2 diabetes and obesity develop
  • A high flux of fructose to the liver, the main organ capable of metabolizing this simple carbohydrate, disturbs normal hepatic carbohydrate metabolism leading to two major consequences (Figure 2): perturbations in glucose metabolism and glucose uptake pathways, and a significantly enhanced rate of de novo lipogenesis and TG synthesis, driven by the high flux of glycerol and acyl portions of TG molecules coming from fructose catabolism
  • Nathan Goodyear on 16 Sep 13
     
    Fructose and metabolic syndrome.  Good discussion of the impact of high fructose intake and metabolic dysfunction.  This study also does a great job of highlighting the historical change of fructose intake.
Nathan Goodyear

Precocious Puberty and Normal Variant Puberty: Definition, etiology, diagnosis and current management - 0 views

www.ncbi.nlm.nih.gov/...PMC3005651

precocious puberty puberty hormones

shared by Nathan Goodyear on 21 Jul 14 - No Cached
  • Nathan Goodyear on 21 Jul 14
     
    nice review of Precocious puberty.
Nathan Goodyear

Obese Americans now outweigh the merely overweight | Reuters - 0 views

www.reuters.com/...sity-usa-idUSTRE50863H20090109

obese overweight americans statistics obesity weight loss

shared by Nathan Goodyear on 15 Apr 11 - No Cached
  • Numbers posted by the National Center for Health Statistics show that more than 34 percent of Americans are obese, compared to 32.7 percent who are overweight. It said just under 6 percent are "extremely" obese.
  • More than one-third of adults, or over 72 million people, were obese in 2005-2006, the NCHS said in its report
  • In May, the CDC reported that 32 percent of U.S. children fit the definition of being overweight, 16 percent were obese and 11 percent were extremely obese.
  • Nathan Goodyear on 15 Apr 11
     
    obesity in America
Nathan Goodyear

http://press.endocrine.org/doi/pdf/10.1210/jc.2014-1872 - 0 views

press.endocrine.org/...jc.2014-1872

low T Testosterone treatment therapy diabetes obesity men male hormone hormones

shared by Nathan Goodyear on 29 Jul 14 - No Cached
  • Nathan Goodyear on 29 Jul 14
     
    New study finds Testosterone therapy provides less than statistical significant improvement in constitutional/sexual symptoms, in obese men with type II diabetes with symptoms classified as mild-moderate with modest reductions in Total Testosterone.  This study highlights that low Testosterone is a biomarker of poor health and multiple comorbidities and that simply adding in Testosterone therapy will not cure all male woes.  The authors did state that ED and low T are separate issues and I will differ with them on this--they are in fact link.  This association may vary between individuals, but to flatly state they are completely separate issues is devoid of the fact that testosterone has been shown to reduce inflammatory cytokines and improve PDE5 therapy.  
Nathan Goodyear

Implications of free radicals and antioxidant levels in carcinoma of the breast: A never-ending battle for survival Sinha R J, Singh R, Mehrotra S, Singh R K - Indian J Cancer - 0 views

www.indianjcancer.com/article.asp

SOD superoxide disumutase catalase antioxidants antioxidant breast cancer cancer malondialdehyde MDA lipid peroxides oxidative stress inflammation

shared by Nathan Goodyear on 10 Nov 14 - No Cached
  • Experimental investigations as well as clinical and epidemiological findings have provided evidence supporting the role of reactive oxygen metabolites or free radicals such as singlet oxygen O 2 - , superoxide anions (O 2 ), hydrogen peroxide (H­2 O2 ) and hydroxyl radical in the etiology of cancer.
  • Certain aldehydes such as Malonyldialdehyde (MDA), the end product of lipid peroxidation arising from free radical degeneration of polyunsaturated fatty acids can cause cross linking in lipids, proteins and nucleic acids leading to cellular damage.
  • In this study, patients with cancer exhibited higher levels of MDA, both in tissues and serum (p&lt;0.001) compared to the control group [Table 1]. In tissue, the MDA level in stage IV was significantly higher as compared to stage I indicating increased free radical activity with increasing severity of cancer
  • ...6 more annotations...
  • From these observations, it can be concluded that MDA levels play an important role in assessing the outcome of cancer
  • SOD and CAT are considered primary antioxidant enzymes, since they are involved in direct elimination of reactive oxygen metabolites. [13-16] They also act as anti-carcinogens and inhibitors at initiation and promotion/transformation stage in carcinogenesis
  • In our study, SOD and CAT levels were found to be low in all cancer patients as compared to controls
  • Fridovich and Tayarani have demonstrated in their respective studies that the reduction in SOD activity increases the toxic effects of O2 - and this might lead to severe cellular damage.
  • Mehrotra et al. in their study also observed high levels of MDA and low levels of SOD and CAT in patients of cancer cervix which is in sync with our observations.
  • strong evidence regarding the definitive role of free radicals in breast malignancy.
  • Nathan Goodyear on 10 Nov 14
     
    This study finds a strong correlation between advancing breast cancer, decreased catalase and SOD with increasing MDA.  The authors of this study conclude this is a key factor in carcinogenesis and not a by-product of cancer.  This flies in the face of traditional medicines fear of antioxidant therapy in cancer.
Nathan Goodyear

International Journal of Obesity - Identification of skeletal muscle mass depletion across age and BMI groups in health and disease[mdash]there is need for a unified definition - 0 views

www.nature.com/...ijo2014161a.html

Muscle mass fat free mass lead dry mass fat obesity body composition muscle muscle loss sarcopenic obesity sarcopenia

shared by Nathan Goodyear on 18 Nov 15 - No Cached
  • Nathan Goodyear on 18 Nov 15
     
    good article to review the components of body composition.
Nathan Goodyear

Sarcopenic obesity - definition, etiology and consequences - 0 views

www.ncbi.nlm.nih.gov/...PMC2633408

obesity sarcopenic obesity sarcopenia

shared by Nathan Goodyear on 18 Nov 15 - No Cached
  • Nathan Goodyear on 18 Nov 15
     
    good discussion of sarcopenic obesity
Nathan Goodyear

How We Read Oncologic FDG PET/CT | Cancer Imaging | Full Text - 0 views

cancerimagingjournal.biomedcentral.com/...s40644-016-0091-3

PET_CT PET scan CT cancer

shared by Nathan Goodyear on 20 Feb 18 - No Cached
  • In early PET literature focusing on analysis of solitary pulmonary nodules, some researchers defined malignancy based on a SUVmax threshold of greater than 2.5
  • We contend that SUV analysis has virtually no role in this setting.
  • tumours grow as spheres, whereas inflammatory processes are typically linear
  • ...35 more annotations...
  • Far more important than the SUVmax is the pattern rather than intensity of metabolic abnormality and the correlative CT findings
  • Descriptively, we define SUV &lt; 5 as “low intensity”, 5–10 as “moderate”, 10–15 as “intense” and &gt;15 as “very intense”
  • Evolving literature suggests that intensity of uptake is an independent prognostic factor and in some tumour subtypes superior to histopathologic characterisation.
  • aerobic glycolysis
  • Our practice of thresholding the grey and colour scale to liver as detailed above results in similar image intensity to a fixed upper SUV threshold of 8 to 10
  • The advantage of using the liver as a reference tissue is also aided by this organ having rather low variability in metabolic activity
  • When the liver is abnormal and cannot be used as a reference organ, we use the default SUV setting of an upper SUV threshold of 8
  • One of the most challenging aspects of oncologic FDG PET/CT review, however, is to recognise all the patterns of metabolic activity that are not malignant and which consequently confound interpretation
  • Many benign and inflammatory processes are also associated with high glycolytic activity
  • Future articles in the “How I Read” series will address the specific details of reading PET/CT in various cancers
  • The intensity of uptake in metastases usually parallels that in the primary site of disease
  • For example, discordant low-grade activity in an enlarged lymph node in the setting of intense uptake in the primary tumour suggests it is unlikely malignant and more likely inflammatory or reactive
  • By CT criteria the enlarged node is ‘pathologic’ but the discordantly low metabolic signature further characterises this is as non-malignant since such a node is not subject to partial volume effects and therefore the intensity of uptake should be similar to the primary site
  • The exception is when the lymph node is centrally necrotic as a small rim of viable tumour is subject to partial volume effects with expectant lower intensity of uptake; integrating the CT morphology is therefore critical to reaching an accurate interpretation
  • Small nodes that are visualised on PET are conversely much more likely to be metastatic as such nodes are subject to partial volume effects.
  • The exception to this rule is tumours with a propensity for tumour heterogeneity at different sites
  • The combination of FDG and a more specific tracer, which visualises the well-differentiated disease can be very useful to characterise this phenomenon
  • “metabolic signature”
  • For the majority of malignant processes, the intensity of metabolic abnormality correlates with degree of aggressiveness or proliferative rate.
  • a negative PET/CT study in a patient with biopsy proven malignancy would be considered false-negative
  • Warburg effect
  • There, however, are a significant minority of tumours that utilise substrates other glucose such as glutamine or fatty acids as a source of the carbon atoms required for growth and proliferation
  • This includes a subset of diffuse gastric adenocarcinomas, signet cell colonic adenocarcinomas and some sarcomas, particularly liposarcoma
  • There may be a role for other radiotracers such as fluorothymidine (FLT) or amino acid substrates in this setting.
  • Some tumours harbour mutations that result in defective aerobic mitochondrial energy metabolism, effectively simulating the Warburg effect
  • patients with hereditary paraganglioma and pheochromocytoma highlight this phenomenon
  • These have intense uptake on FDG PET/CT despite often having low proliferative rate.
  • Uterine fibroids, hepatic adenomas, fibroadenomas of the breast and desmoid tumours are benign or relatively benign lesions that can have quite high FDG-avidity.
  • Metabolic activity switches off rapidly following initiation of therapy
  • Common examples where patients have commenced active therapy but the referrer is requesting “staging” includes hormonal therapy (eg. tamoxifen) in breast cancer, oral capecitabine in colorectal cancer or high dose steroids in Hodgkin’s lymphoma
  • It is therefore critical to perform PET staging before commencement of anti-tumour therapy
  • The potential advantage of routine diagnostic CT is improved anatomic localisation and definition
  • Without intravenous contrast, additional identification of typical oncologic complications such as pulmonary embolism or venous thrombosis cannot be identified
  • If the study is performed as an “interim” restaging study after commencement of therapy but before completion, in order to reach a valid or clinically useful conclusion findings must be interpreted in the context of known changes that occur at a specific timing and type of therapy
  • The most well studied use of interim PET is in Hodgkin’s lymphoma where repeat PET after two cycles of ABVD-chemotherapy provides powerful prognostic information and may improve outcomes by enabling early change of management
  • Nathan Goodyear on 20 Feb 18
     
    good read on the PET/CT scan reading.  They mention that tumors are spheres and inflammation is linear, yet inflammation coexists with cancer; hard to simply delineate these on simple terms. I do agree aon the metabolic signature of the PET/CT scan
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