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Nathan Goodyear

Availability of evidence of benefits on overall survival and quality of life of cancer ... - 0 views

  • Although the goal of cancer treatment is to improve the quantity and quality of life,123 clinical trials designed to gain regulatory approval for new drugs often evaluate indirect or “surrogate” measures of drug efficacy. These endpoints show that an agent has biological activity, but they are not reliable surrogates for improved survival4567891011 or quality of life46111213
  • two recent systematic reviews suggest that the strength of association between surrogates in cancer clinical trials and life extension is generally low
  • Available data from the US show that only a small proportion of cancer treatments approved by the US Food and Drug Administration (FDA) unequivocally show benefits on survival or quality of life.30
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  • We sought to systematically evaluate the evidence base for all new drugs and new indications for the treatment of solid tumours and haematological malignancies approved by the EMA in the five year period 2009-13
  • Three investigators (AP, EP, and EG) independently extracted data on and descriptively analysed the following trial features: characteristics of the participant population, study design (randomisation, crossover from experimental to control group, and blinding of investigators and participants), experimental and control groups, enrolment, primary and secondary endpoints, magnitude of benefit on survival and quality of life, and narrative interpretation of the findings
  • Only 18 of the 68 (26%) were supported by a pivotal study powered to evaluate overall survival as the primary outcome
  • From 2009 to 2013, the EMA approved use of 48 oncology drugs
  • Seventeen drugs were approved for treatment of haematological malignancies and 51 for treatment of solid tumours
  • Overall, 72 clinical trials supported the approval of 68 novel drug uses
  • Our scoring was limited to drugs for solid tumours
  • Among 68 cancer drug indications approved by the EMA in the period 2009-13, and with a median of 5.4 years’ follow-up, only 35 (51%) were associated with a significant improvement in survival (26/35) or quality of life (9/35) over existing treatment options, placebo, or as add on treatment
  • Only two of the 26 drugs shown to extend life also showed benefits on quality of life
  • 33 (49%) had not shown any improvement on survival or quality of life
  • This systematic evaluation of oncology drug approvals by the EMA in 2009-13 shows that most of the drugs (39/68, 57%) entered the market without evidence of improved survival or quality of life
  • At a minimum 3.3 years after market entry, there was still no conclusive evidence that 33 of these 39 cancer drugs either extended or improved life
  • What are potential reasons for the paucity of drug approvals with demonstrable survival advantages over existing treatments?
  • Firstly, only 18 (26%) indications for use in our cohort were supported by trials in which extension of life was the primary outcome
  • None of the pivotal studies supporting oncology drug approvals from 2009 to 2013 included quality of life as a primary outcome measure
  • Most new oncology drugs authorised by the EMA in 2009-13 came onto the market without clear evidence that they improved the quality or quantity of patients’ lives
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    New study from European Medicines Agency questions alot of the new cancer drugs brought to the market 2009-2013.  57% of the new drugs (39/68) were brought to the market without evidence of improved survival or quality of life.
Nathan Goodyear

Intravenous vitamin C in the supportive care of cancer patients: a review and rational ... - 0 views

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    Review of vitamin C in cancer treatment
Nathan Goodyear

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

  • 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
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  • 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
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    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

Disseminated Intravascular Coagulation (DIC) - Hematology and Oncology - Merck Manuals ... - 0 views

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    good review of DIC
Nathan Goodyear

JAMA Network | JAMA Oncology | The Preventability of Cancer:  Stacking the Deck - 0 views

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    Lifestyle interventions to prevent cancer
Nathan Goodyear

JAMA Network | JAMA Oncology | Preventable Incidence and Mortality of Carcinoma Associa... - 0 views

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    Health lifestyle interventions reduce the incidence and mortality from cancer.
Nathan Goodyear

http://www.cancernetwork.com/oncology-journal/how-we-treat-tumor-lysis-syndrome/page/0/3 - 0 views

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    Good review of diagnosis and treatment of tumor lysis syndrome. Increased risk in lymphomas and leukemia's.
Nathan Goodyear

Immuno-oncology: understanding the function and dysfunction of the immune system in cancer - 0 views

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    Great review of the immune system and cancer.
Nathan Goodyear

Vitamin C preferentially kills cancer stem cells in hepatocellular carcinoma via SVCT-2... - 0 views

  • Chen et al. have revealed that ascorbate at pharmacologic concentrations (0.3–20 mM) achieved only by intravenously (i.v.) administration selectively kills a variety of cancer cell lines in vitro, but has little cytotoxic effect on normal cells.
  • Ascorbic acid (the reduced form of vitamin C) is specifically transported into cells by sodium-dependent vitamin C transporters (SVCTs)
  • SVCT-1 is predominantly expressed in epithelial tissues
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  • whereas the expression of SVCT-2 is ubiquitous
  • differential sensitivity to VC may result from variations in VC flow into cells, which is dependent on SVCT-2 expression.
  • high-dose VC significantly impaired both the tumorspheres initiation (Fig. 4d, e) and the growth of established tumorspheres derived from HCC cells (Fig. 4f, g) in a time-dependent and dose-dependent manner.
  • Hepatocellular carcinoma (HCC)
  • The antioxidant, N-acetyl-L-cysteine (NAC), preventing VC-induced ROS production (a ROS scavenger), completely restored the viability and colony formation among VC-treated cells
  • DNA double-strand damage was found following VC treatment
  • DNA damage was prevented by NAC
  • Interestingly, the combination of VC and cisplatin was even more effective in reducing tumor growth and weight
  • Consistent with the in vitro results, stemness-related genes expressions in tumor xenograft were remarkably reduced after VC or VC+cisplatin treatment, whereas conventional cisplatin therapy alone led to the increase of CSCs
  • VC is one of the numerous common hepatoprotectants.
  • Interestingly, at extracellular concentrations greater than 1 mM, VC induces strong cytotoxicity to cancer cells including liver cancer cells
  • we hypothesized that intravenous VC might reduce the risk of recurrence in HCC patients after curative liver resection.
  • Intriguingly, the 5-year disease-free survival (DFS) for patients who received intravenous VC was 24%, as opposed to 15% for no intravenous VC-treated patients
  • Median DFS time for VC users was 25.2 vs. 18 months for VC non-users
  • intravenous VC use is linked to improved DFS in HCC patients.
  • In this study, based on the elevated expression of SVCT-2, which is responsible for VC uptake, in liver CSCs, we revealed that clinically achievable concentrations of VC preferentially eradicated liver CSCs in vitro and in vivo
    • Nathan Goodyear
       
      the authors here made similar mistakes to the Mayo authors i.e. under doses here in this study.  They dosed at only 2 grams IVC.  A woefully low dose of IVC.
  • Additionally, we found that intravenous VC reduced the risk of post-surgical HCC progression in a retrospective cohort study.
    • Nathan Goodyear
       
      positive results despite a low dose used.
    • Nathan Goodyear
       
      Their comfort zone was 1mM.  They should have targeted 20-40 mM.
  • Three hundred thirty-nine participants (55.3%) received 2 g intravenous VC for 4 or more days after initial hepatectomy
  • As the key protein responsible for VC uptake in the liver, SVCT-2 played crucial roles in regulating the sensitivity to ascorbate-induced cytotoxicity
  • we also observed that SVCT-2 was highly expressed in human HCC samples and preferentially elevated in liver CSCs
  • SVCT-2 might serve as a potential CSC marker and therapeutic target in HCC
  • CSCs play critical roles in regulating tumor initiation, relapse, and chemoresistance
  • we revealed that VC treatment dramatically reduced the self-renewal ability, expression levels of CSC-associated genes, and percentages of CSCs in HCC, indicating that CSCs were more susceptible to VC-induced cell death
  • as a drug for eradicating CSCs, VC may represent a promising strategy for treatment of HCC, alone or particularly in combination with chemotherapeutic drugs
  • In HCC, we found that VC-generated ROS caused genotoxic stress (DNA damage) and metabolic stress (ATP depletion), which further activated the cyclin-dependent kinase inhibitor p21, leading to G2/M phase cell cycle arrest and caspase-dependent apoptosis in HCC cells
  • we demonstrated a synergistic effect of VC and chemotherapeutic drug cisplatin on killing HCC both in vitro and in vivo
  • Intravenous VC has also been reported to reduce chemotherapy-associated toxicity of carboplatin and paclitaxel in patients,38 but the specific mechanism needs further investigation
    • Nathan Goodyear
       
      so, exclude the benefit to patients until the exact mechanism of action, which will never be fully elicited?!?!?
  • Our retrospective cohort study also showed that intravenous VC use (2 g) was related to the improved DFS in HCC patients after initial hepatectomy
    • Nathan Goodyear
       
      Terribly inadequate dose.  Target is 20-40 mM which other studies have found occur with 50-75 grams of IVC.
  • several clinical trials of high-dose intravenous VC have been conducted in patients with advanced cancer and have revealed improved quality of life and prolonged OS
  • high-dose VC was not toxic to immune cells and major immune cell subpopulations in vivo
  • high recurrence rate and heterogeneity
  • tumor progression, metastasis, and chemotherapy-resistance
  • SVCT-2 was highly expressed in HCC samples in comparison to peri-tumor tissues
  • high expression (grade 2+/3+) of SVCT-2 was in agreement with poorer overall survival (OS) of HCC patients (Fig. 1c) and more aggressive tumor behavior
  • SVCT-2 is enriched in liver CSCs
  • these data suggest that SVCT-2 is preferentially expressed in liver CSCs and is required for the maintenance of liver CSCs.
  • pharmacologic concentrations of plasma VC higher than 0.3 mM are achievable only from i.v. administration
  • The viabilities of HCC cells were dramatically decreased after exposure to VC in dose-dependent manner
  • VC and cisplatin combination further caused cell apoptosis in tumor xenograft
  • These results verify that VC inhibits tumor growth in HCC PDX models and SVCT-2 expression level is associated with VC response
  • qPCR and IHC analysis demonstrated that expression levels of CSC-associated genes and percentages of CSCs in PDXs dramatically declined after VC treatment, confirming the inhibitory role of VC in liver CSCs
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    IV vitamin C in vitro and in vivo found to "preferentially" eradicate cancer stem cells.  In addition, IV vitamin C was found to be adjunctive to chemotherapy, found to be hepatoprotectant.  This study also looked at SVCT-2, which is the transport protein important in liver C uptake.
Nathan Goodyear

The Repurposing Drugs in Oncology (ReDO) Project - 0 views

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    Repurposing old drugs for the new fight in cancer.
Nathan Goodyear

Repurposing Drugs in Oncology (ReDO)-mebendazole as an anti-cancer agent. ecancermedica... - 0 views

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    Good read on mebendazole's effect in a variety of cancer types.
Nathan Goodyear

Therapeutic hyperthermia: The old, the new, and the upcoming - Critical Reviews in Onco... - 1 views

  • not well understood, but it is felt to be a combination of both heat-induced necrosis and of protein inactivation (e.g., repair enzymes) as opposed to DNA damage
  • alterations in tumor cytoskeletal and membrane structures, which disrupt cell motility and intracellular signal transduction
  • A common explanation for HT-enhancement of RT and CT involves inhibition of homologous recombination repair of double-strand DNA breaks, preventing cells from repairing sub-lethal damage
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  • it does appear to inhibit rejoining of RT-induced DNA breaks more than is commonly observed after RT alone
  • HT damages cells and enhances RT and CT sensitivity as a function of both temperature and duration of treatment
  • as temperature or duration increase, the rate of cell killing also increases
  • At temperatures above 42 °C, tumor vasculature is damaged, resulting in decreased blood flow
  • Cancer cells are particularly vulnerable to heating; in vivo studies have shown that temperatures in the range of 40–44 °C cause more selective damage to tumor cells
  • cancerous blood vessels are chaotic, leaky, and inefficient
  • selective cytotoxic effect on tumor cells include inhibition of key cancer cell-signaling pathways such as AKT, inducing apoptosis, suppression of cancer stem cell proliferation, and others
  • increase in immunological attacks against tumors after HT, which were believed to be achieved through activation of HSPs and subsequent modulation of the innate and adaptive immune responses against tumor cells
  • HT does lead to activation of the immune system and HSP-induced cell death through modification of the tumor cell surface
  • These HSPs and tumor antigens are taken up by dendritic cells and macrophages and go on to induce specific anti-tumor immunity
  • In vivo studies demonstrate HT-enhancement of NK cell activity, and HT has been shown to increase neutrophilic granulocytes with anti-tumor activity
  • it has become increasingly clear that HT results in immune stimulation, through both direct heat-mediated cell killing as well as innate and adaptive immune system modulation
  • The term hyperthermia is used in this review to refer to heating within the clinically accepted range of 40–45 °C
  • temperatures above 42.5–43 °C the exposure time can be halved with each 1 °C increase while maintaining equivalent cell killing
  • gradual heating at 43 °C for 1 h worked through an apoptotic pathway
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    Comprehensive review of hyperthemic therapy.
Nathan Goodyear

Galectin-3 as an Oncological Biomarker | Natural Medicine Journal - 0 views

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    Another helpful cancer biomarker to assess/follow.
Nathan Goodyear

Rethinking vitamin C and cancer: an update on nutritional oncology - 0 views

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    1998 article that looks at the cytotoxic effects of vitamin C on cancer cells.
Nathan Goodyear

Testosterone and prostate cancer: an evidence-based review of pathogenesis and oncologi... - 0 views

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    Testosterone therapy is likely safe in selected patients.  Close follow up is imperative and a well informed patient is equally imperative.
Nathan Goodyear

Use of Different Postmenopausal Hormone Therapies and Risk of Histology- and Hormone Re... - 0 views

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    natural progesterone decreased the risk of breast cancer caused by long term use of estrogens in study of 80,000+.  I would have been nice to have seen a progesterone only arm of the study.
Nathan Goodyear

Cognitive Complaints in Survivors of Breast Cancer After Chemotherapy Compared With Age... - 0 views

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    Chemo brain.  Does it exist?  Large study finds significant cognitive decline in follow up at 6 months in breast cancer patients treated with chemo compared to control group.
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