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Nathan Goodyear

PET/CT Standardized Uptake Values (SUVs) in Clinical Practice and Assessing Response to... - 0 views

www.ncbi.nlm.nih.gov/...PMC3026294

cancer PET scan PET_CT CT PET_CT scan

shared by Nathan Goodyear on 20 Feb 18 - No Cached
  • use of PET in clinical research, clinical trials, and drug discovery
  • use of PET/CT in assessing response to therapy
  • In some cases, such as Hodgkins lymphoma, quantitative PET/CT imaging may not actually be needed, as success can be defined by the complete absence of tracer uptake in the PET image following a course of standardized therapy
  • ...9 more annotations...
  • The utilization of PET/CT to assess response to therapy is increasing in the US related, in part, to the creation and subsequent favorable results of the National Oncologic PET Registry (NOPR)
  • Changes in size as a result of therapy may take many months to develop and any opportunity to make early decisions about therapy success or failure is often unduly delayed or lost altogether
  • measures of changes in metabolic activity via FDG PET/CT can provide an alternate approach to assess response to therapy -- often very early in the course of treatment
  • Current recommendations are that tumor SUVs should be reported
  • The true tracer uptake in a patient is composed of two components: the first being the amount of tracer uptake (e.g. FDG) associated with the disease status (the signal of interest), which can be modified by the biophysiological status of the patient. One of the more important patient parameters is the blood glucose level, which has been shown to inversely-linearly affect SUVs
  • A prospective study by Crippa et al.30 in eight patients showed that as blood glucose levels were increased from 92.4 ±10.2 to 158 ± 13.8 mg/100 ml by glucose loading, the average SUV of 20 liver metastases decreased from 9.4 ± 5.7 to 4.3 ± 8.3
  • chemotherapy can result in impaired renal function, significantly reducing the clearance of plasma FDG through the kidney and thus increasing tumor SUV relative to an initial PET scan
  • The second component of the true tracer uptake is biological variability
  • The biological variability has been estimated in several test-retest studies7,32–35 at approximately 10% for scans repeated within a few days
  • Nathan Goodyear on 20 Feb 18
     
    Good review of the SUVs of a PET/CT scan.
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 < 5 as “low intensity”, 5–10 as “moderate”, 10–15 as “intense” and >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
Nathan Goodyear

Evaluation of FLT-PET-CT as an imaging biomarker of proliferation in primary breast can... - 0 views

www.nature.com/...bjc2014207

PET scan PET_CT scan cancer breast

shared by Nathan Goodyear on 19 Mar 18 - No Cached
  • We have demonstrated that the majority of patients have a sizeable reduction in SUVmax from a single cycle of NAC with a mean change of −32.3%
  • This study, however, failed to show any predictive markers of response after one cycle of chemotherapy
  • These data therefore suggest that the main utility of FLT-PET as an imaging biomarker in early breast cancer is pre-chemotherapy, as a marker of proliferation, rather than in predicting pathological response after chemotherapy
  • ...2 more annotations...
  • In terms of the histological proliferation biomarker Ki-67, we have shown a good correlation with FLT-PET pre-chemotherapy. The best predictive marker of response in terms of pCR was baseline Ki-67
  • Our study has shown that baseline Ki-67 and FLT SUVmax is well correlated in keeping with FLT-PETs status as a proliferation biomarker, although Ki-67 had a better predictive ability in terms of pathological outcome
  • Nathan Goodyear on 19 Mar 18
     
    PET CT scan shown to be useful as a proliferation biomarker pre-chemo in breast cancer.
Nathan Goodyear

FDG-PET/CT imaging biomarkers in head and neck squamous cell carcinoma - 0 views

www.ncbi.nlm.nih.gov/...PMC3587845

PET scan cancer PET_CT scan maxSUV

shared by Nathan Goodyear on 19 Mar 18 - No Cached
  • F-fluoro-2-deoxyglucose (FDG) PET/CT is sensitive for the diagnosis and initial staging of several types of malignancies
  • SUV is a semiquantitative measure of the normalized concentration of radioactivity in a tumor or lesion
  • As FDG is the most common radiotracer used clinically and reflects tumor glucose metabolism, SUV is used as a surrogate marker for tumor metabolism.
  • ...9 more annotations...
  • primary tumor SUVmax >10 predicted survival, independent of the tumor stage and diameter
  • advanced tumors tend to have higher FDG uptake (and thus higher SUV values)
  • the impact of the SUV on treatment outcome has been observed even within a given tumor stage
  • The association between FDG uptake and tumor burden or stage has been well documented
  • FDG uptake not only reflects tumor burden/stage but also expresses, at least in part, some intrinsic biologic characteristic(s) of the tumor
  • SUVmax reflects the highest voxel value within the ROI or VOI. It is the most widely used parameter to measure metabolic tumor activity in oncologic FDG-PET/CT imaging
  • Several studies suggest that primary tumor baseline SUVmax also has predictive value in assessing the tumor burden, lymph node involvement and local extension
  • According to EORTC, a drop (delta between baseline and post-therapy) of 15–25% in SUVmax may represent a good treatment response
  • PERCIST criteria was proposed by the investigators at the Johns Hopkins Medical Institutions and suggested that a decrease in SUV normalized to lean body mass of at least 30% should be achieved before considering partial tumor response
  • Nathan Goodyear on 19 Mar 18
     
    Good review of PET/CT scan and MaxSUV in head and neck cancers.
Nathan Goodyear

18FDG-PET/CT for predicting the outcome in ER+/HER2- breast cancer patients: comparison... - 0 views

breast-cancer-research.biomedcentral.com/...s13058-016-0793-2

PET scan cancer breast cancer

shared by Nathan Goodyear on 19 Mar 18 - No Cached
  • our study confirms that baseline PET parameters measured before neoadjuvant treatment have prognostic values in ER+/HER2- locally advanced breast cancer patients
  • It has been suggested that high baseline 18F-fluorodeoxyglucose (18FDG) uptake assessed by high standardized uptake value (SUV) could be associated with poor prognostic factors such as the high histological grade [2] as well as worse survival
  • several teams observed that the change in SUV values early during neoadjuvant treatment could be a good indicator of pathological response and potentially outcome
  • ...5 more annotations...
  • others studies suggested that baseline 18FDG uptake, which would avoid performing a second examination, could also be of interest to predict patient outcome, especially in ER+/HER2- BC
  • ER+/HER2- BC has less intense 18FDG uptake than some other phenotypes such as TN carcinoma
  • Patients with high baseline 18FDG tumor uptake are at higher risk of early recurrence
  • The 3-year EFS was 78.4% in patients with baseline tumor SUVmax > 8.3 (vs. 94.0% in those with SUVmax ≤ 8.3)
  • event-free survival (EFS)
  • Nathan Goodyear on 19 Mar 18
     
    Study finds benefit of PET scan in prognosis in ER+/HER2- breast cancers.
Nathan Goodyear

Metabolic PET Imaging in Cancer Detection and Therapy Response - 0 views

www.ncbi.nlm.nih.gov/...PMC3075495

PET scan cancer

shared by Nathan Goodyear on 18 Mar 18 - No Cached
  • Nathan Goodyear on 18 Mar 18
     
    PET scans sensitivity and specificity in cancer.
Nathan Goodyear

http://www.jto.org/article/S1556-0864(15)33156-7/pdf - 0 views

www.jto.org/...pdf

PET scan cancer

shared by Nathan Goodyear on 18 Mar 18 - No Cached
  • Nathan Goodyear on 18 Mar 18
     
    good commentary on PET scan SUV values.
Nathan Goodyear

Testosterone Treatment Enhances Regional Brain Perfusion in Hypogonadal Men: The Journa... - 0 views

press.endocrine.org/...jc.2002-020632

low T low testosterone brain cognition ED Testosterone therapy male hormones

shared by Nathan Goodyear on 09 Jan 17 - No Cached
  • it is established that androgen modulates various neurotransmitters in the CNS. Testosterone decreases γ-aminobutyric acid concentration in the hypothalamus, which is blocked by flutamide, a testosterone receptor blocker (14, 15). Testosterone, probably by its conversion to estradiol, increases serotonin transporter mRNA expression in dorsal raphe nucleus (16), and it also increases the density of 5-hydroxytryptamine receptors and serotonin transporter sites in the forebrain (3, 16) of castrated male rats.
  • Nathan Goodyear on 09 Jan 17
     
    very interesting study of 7 men.  Increase brain perfusion found and symptom improvement as a result of Testosterone therapy in men ages 58-72.  Specific increase perfusion by SPECT scans were in the midbrain and Brodman areas 8 and 24 of the cerebral cortex.
Nathan Goodyear

Role of maximum standardized uptake value in fluorodeoxyglucose positron emission tomog... - 0 views

www.ncbi.nlm.nih.gov/...PMC3785187

PET scan PET_CT scan maxSUV cancer breast

shared by Nathan Goodyear on 19 Mar 18 - No Cached
  • 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is an effective and popular technique for evaluating patients before and after breast cancer surgery.
  • Quantitative FDG-PET/CT imaging is becoming prevalent in cancer treatment as it measures glucose metabolism that reflects the growth potential and metabolic activity of malignant tumors
  • The FDG-PET/CT findings of primary lesions in colorectal and lung cancers correlate with metastasis and prognosis because FDG reflects tumor viability
  • ...15 more annotations...
  • The technique is valuable for predicting the prognosis of patients with recurrent breast cancer and for determining and predicting the outcomes of neoadjuvant chemotherapy
  • FDG-PET/CT is useful not only for evaluating metastasis but also for predicting the prognosis of recurrent breast cancer and measuring treatment effects
  • reports remain limited to small-scale clinical trials of about 100 patients.
  • MaxSUV, which is the most popular FDG-PET/CT value, can vary up to 30 % because of differences among PET/CT devices and among the operators who create the images
  • the degree of malignancy would increase with an increase in maxSUV when ER or HER-2 signaling is involved.
  • Factors that determine the rate of cancer progression include T-factor (tumor diameter) and N-factor (presence or absence/number of lymph node metastasis)
  • Factors that determine the nature of tumors also include ER, HER-2, Ki-67 labeling index, and nuclear grade
  • Prognosis was previously predicted based on T, N, and M staging, which indicates the degree of progression. However, prognosis is now predicted and treatment regimes are presently selected by also considering ER and HER-2 levels, which determine the nature of the tumor
  • maxSUV presently serves as an indicator of metabolic activity during cancer therapy. For instance, the maxSUV of primary lung and hematological cancer lesions correlates with metastasis and prognosis, whereas maxSUV also seems useful for predicting the prognosis of recurrent breast cancer and in determining and predicting the outcome of neoadjuvant chemotherapy
  • The maxSUV cut-off calculated from ROC curves for recurrence was 3.0
  • The prognostic factors applied in breast cancer can be broadly divided into those that determine staging and those that determine biological tumor characteristics
  • both ER status and maxSUV as independent prognostic factors
  • maxSUV has a closer correlation with prognosis
  • maxSUV, clinical T-factor and ER were significant prognostic factors
  • Our results showed that maxSUV has the potential to be a novel prognostic factor and that it can be used to determine future therapies
  • Nathan Goodyear on 19 Mar 18
     
    Retrospective, multi-facility finds maxSUV can be used in prognosis in cancer.  Others have shown benefit in recurrence risk.  MaxSUV was found to be an independent factor.
Nathan Goodyear

The maximum standardized uptake values on integrated FDG-PET/CT is useful in differenti... - 0 views

www.ncbi.nlm.nih.gov/...16928527

cancer PET scan PET_CT scan maxSUV

shared by Nathan Goodyear on 19 Mar 18 - No Cached
  • Nathan Goodyear on 19 Mar 18
     
    A maxSUB of 0 to 2.5 of a suspicious nodule has a 24% chance or being malignant.  This would increase with a primary malignancy.
fnfdoc

Types Causes And Symptoms Of Brain Tumor | Your Health Our Priority - 0 views

www.fnfdoc.com/...es-causes-symptoms-brain-tumor

Brain Tumor Glial Cells Health Types Of

shared by fnfdoc on 28 Apr 18 - No Cached
  • fnfdoc on 28 Apr 18
     
    Brain Tumor risks including surgery facts, as well as diagnosis also types either the primary tumor or secondary tumor. Treatments like MRI CT scan helping you to decide better for your health.
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.
umar111

Computer Science: Computer hardware - 0 views

computersciencetopper.blogspot.com/...computer-hardware.html

Best computer computer computer Science it blog

shared by umar111 on 26 Apr 23 - No Cached
  • umar111 on 26 Apr 23
     
    Computer Science Tuesday, April 25, 2023 Computer hardware Computer hardware is the physical components that make up a computer system. It includes everything from the central processing unit (CPU) to the monitor, keyboard, and mouse. Understanding the different types of hardware and how they work together is essential for anyone who works with computers. In this article, we will explore the various components of computer hardware, including internal and external components, and the peripherals that connect to them. We will also discuss the importance of hardware maintenance, the latest advancements in computer technology, and factors to consider when choosing the right hardware for your needs. Whether you are a computer technician, a gamer, or simply someone who uses a computer for everyday tasks, this article will help you better understand the world of computer hardware. Introduction to Computer Hardware Computer hardware refers to the physical components that make up a computer system. It includes everything from the processor and memory to input/output devices such as the keyboard and monitor. In this article, we will explore the different types of computer hardware and their functions. What is Computer Hardware Computer hardware refers to the physical components of a computer system. It includes all the components that can be touched, seen, and used to interact with a computer, such as the monitor, keyboard, and mouse. Hardware is different from computer software, which refers to the programs and applications that run on a computer system. History of Computer Hardware The history of computer hardware dates back to the 1820s when Charles Babbage, an English mathematician, and inventor, designed the first analytical engine, which was considered to be the first mechanical computer. With time, more complex electronic computers were developed, including the first Intel microprocessor in 1971. Since then, computer hardware has continued to evolve, becoming
Nathan Goodyear

Study of curcumin on microvasculature characteristic in diabetic rat's liver as reveale... - 0 views

www.ncbi.nlm.nih.gov/...22934459

curcumin curcuma longa turmeric liver liver enzymes liver disease diabetes

shared by Nathan Goodyear on 06 Jul 16 - No Cached
  • Nathan Goodyear on 06 Jul 16
     
    Curcumin at 200 mg/kg found to aid liver repair, regeneration in animal study of diabetes.
Nathan Goodyear

Dental "silver" tooth fillings: a source of mercury exposure revealed by whole-body ima... - 0 views

www.fasebj.org/...2641.short

mercury fillings amalgams tooth teeth dental

shared by Nathan Goodyear on 04 Sep 11 - No Cached
  • Nathan Goodyear on 04 Sep 11
     
    Mercury and fillings.  Danger
helensvalechiro

Helensvale Chiropractor - 0 views

www.helensvalechiropractor.net.au

Helensvale Chiropractic Centre Chiropractor Massage Cellular Health Analysis Thermography Scan Remedial Sports Deep Tissue Relaxation Detox weight loss

shared by helensvalechiro on 25 Dec 15 - No Cached
  • helensvalechiro on 25 Dec 15
     
    At Helensvale Chiropractor we not only look after chiropractic but we are also a complete integrated wellness centre for weight loss, detox, VLA etc.
Nathan Goodyear

Immunotherapy for Prostate Cancer with Gc Protein-Derived Macrophage-Activating Factor,... - 0 views

europepmc.org/...PMC2510818

GC-MAF Nagalase cancer prostate cancer immunotherapy PSA

shared by Nathan Goodyear on 08 May 18 - No Cached
  • the MAF precursor activity of prostate cancer patient Gc protein is lost or reduced, because their serum Gc protein is deglycosylated by serum α-N-acetylgalactosaminidase (Nagalase) secreted from cancerous cells
  • Administration of 100 ng of GcMAF
  • 100 ng of GcMAF was administered intramuscularly once a week
  • ...11 more annotations...
  • As GcMAF therapy progressed the MAF precursor activity of all five patients increased and their serum Nagalase activity decreased inversely
  • As GcMAF therapy progressed, the MAF precursor activity increased with a concomitant decrease in serum Nagalase activity
  • serum Nagalase is proportional to tumor burden
  • as GcMAF therapy progressed, serum Nagalase activity decreased and, concomitantly, tumor burden decreased
  • the serum Nagalase activities of all 16 patients decreased as GcMAF therapy progressed
  • annual computed tomographic scans of these patients confirmed them being tumor recurrence-free for the 7 years
  • undifferentiated cells were killed rapidly during the first few weeks, and the differentiated cells were killed slowly in the remaining GcMAF therapeutic period
  • PSA levels of prostatectomized patients decreased as serum Nagalase decreased during GcMAF therapy
  • In patients without tumor resection, however, although serum Nagalase activity decreased as GcMAF therapy progressed, their PSA values remained unchanged. The result suggests that the PSA derived from tumor-bearing prostate did not change while tumor burden decreased. Because tumor-induced inflammation in the noncancerous prostate tissues causes secretion of PSA [38], the PSA produced from these inflamed noncancerous prostate tissues cannot be changed by the decrease in tumor burden
  • Advanced cancer patients have high serum Nagalase activities, resulting in no macrophage activation and severe immunosuppression that explain why cancer patients die with overwhelming infection
  • Prognostic utility of serum α-N-acetylgalactosaminidase and immunosuppression resulted from deglycosylation of serum Gc protein in oral cancer patients
  • Nathan Goodyear on 08 May 18
     
    GC-MAF levels exist in inverse relationship to nagalase.  In this study of men with prostate cancer, weekly GCMAF injections reduced Nagalase activity to levels found in healthy controls suggesting tumor free. The dose was 100 ng/week. Nagalase is a protein that suppresses GC-MAF production and thus is immunosuppressive.
Nathan Goodyear

Outcompeting p53-Mutant Cells in the Normal Esophagus by Redox Manipulation - ScienceDi... - 0 views

www.sciencedirect.com/...S1934590919302759

cancer radiation cat scan imaging CT

shared by Nathan Goodyear on 19 Jul 19 - No Cached
  • Nathan Goodyear on 19 Jul 19
     
    Low dose radiation from CT found to contribute to altered genetic expression of p53 tumor suppressor gene to give competitive advantage to potential cancer cells over health cells.
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