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Potential Problems Related to Cancer Treatment

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POTENTIAL PROBLEMS RELATED TO CANCER TREATMENT By Catherine M. Handy, Ph.D., RN, AOCN Oncology Clinical Nurse Specialist – PowerPoint PPT presentation

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Title: Potential Problems Related to Cancer Treatment


1
Potential Problems Related to Cancer Treatment
  • By Catherine M. Handy, Ph.D., RN, AOCN
  • Oncology Clinical Nurse Specialist

2
Current Anti-Cancer Approaches
3
Surgery
  • Surgery is the oldest and the most investigated
    therapy for cancer.
  • Many different rationales for cancer-related
    surgeries
  • Diagnostic To obtain tissue necessary for
    diagnosis and staging
  • Curative To remove entire tumor with adequate
    margins of normal tissue
  • Preventive or prophylactic To reduce risk of
    cancer developing in high-risk patients
  • Esophageal resection for Barretts esophagus
  • Bilateral mastectomy for BRCA mutations
  • Palliative To treat cancer symptoms, not cure
  • Tumor debulking
  • Esophageal stent placement

4
Radiation Therapy Indications
  • Can be the primary treatment
  • Used before surgery to shrink tumor
  • Used after chemotherapy or surgery to get tumor
    cells left behind
  • Delivered to high-risk areas to prevent cancer
    growth
  • Used to control cancer
  • Used to manage symptoms or to improve quality of
    life
  • Used to treat structural emergencies

5
Radiation Therapy Side Effects
  • General
  • Fatigue
  • Skin
  • All other toxicities are particular to the organs
    that were in the treatment field
  • For example, if a patient received radiation
    therapy for lung cancer the esophagus, heart,
    spinal cord and perhaps the thyroid also received
    some radiation

6
Chemotherapy vs. Targeted Therapies
  • Cytotoxic Chemotherapy
  • Poisonous substances that interrupt normal
    cellular division in proliferating cells and are
    more effective in cancer cells due to the rapid
    proliferation of tumors
  • Dosages generally based on BSA (Pediatric and
    specific agent doses may differ.)
  • Biotherapy/Targeted Therapies
  • Designed to interfere with specific molecules or
    signaling pathways involved in tumor growth and
    progression
  • Dosed in mg, units, m2

7
Hormone Side Effects
  • Anti-estrogens
  • Menopause
  • VTE
  • Osteopenia/osteoporosis
  • Medical castration agents
  • Feminization

8
Chemotherapy General Side Effects
  • Myelosuppression
  • GI
  • Mucositis
  • N/V
  • Diarrhea
  • Alopecia
  • Renal

9
Monoclonal Antibody Side Effects
  • Hypersensitivity reactions less mouse and more
    human less chance of hypersensitivity
  • EGFR
  • Skin toxicity
  • VEGF
  • Vascular toxicity
  • CD 20
  • lymphopenia

10
Kinase Inhibitor Side Effects
  • Because they are po, uncertain absorption
  • Possible interference with metabolism of other
    drugs and interaction with enzymes or proteins
    other than designated target (e.g. cytochrome
    P450 enzyme)

11
Peripheral Neuropathy (PN)orChemotherapy-Induced
Peripheral Neuropathy (CIPN)
12
Definition
  • Often thought to refer only to numbness and
    tingling of the hands or feet
  • PN is a group of neurologic dysfunctions that
    occur outside the spine and brain.
  • Refers to any part of the body affected by
    peripheral nerves

13
Incidence
  • In those receiving neurotoxic chemotherapeutic
    agents, the incidence of developing PN can range
    from 10 to 100.

14
Risk Factors
  • Comorbidities
  • Diabetes
  • Alcohol overuse
  • Metabolic imbalances
  • Vitamin B12 deficiency
  • Cachexia
  • HIV
  • Other paraneoplastic syndrome
  • Cancer
  • Age
  • Medications

15
Pathophysiology
  • CIPN is not understood totally.
  • Can vary depending on the type of chemotherapy
    given
  • Chemotherapy is believed to damage the sensory
    axons first and then cause degeneration and dying
    of axons and myelin sheaths.

16
Pathophysiology
  • Axons can regenerate if the offending agent is
    removed.
  • Damage to cell bodies is often not completely
    reversible.

17
Characteristics
  • Sensory CIPN
  • Negative manifestations such as numbness or
    reduced sensation
  • Positive symptoms/pain sensations such as
    paresthesia, dysesthesia, causalgia, and
    allodynia
  • Large sensory nerve damage may result in
    decreased deep tendon reflexes and vibratory
    sense, ataxia, and abnormal position sense of
    body parts.

18
Characteristics
  • Motor CIPN and autonomic CIPN are uncommon.
  • Motor CIPN is difficult to characterize as it is
    related to sensory damage, such as weakness, loss
    of feeling, or foot pain.
  • Autonomic CIPN can cause nausea, abdominal
    fullness or bloating, early satiety,
    constipation, urinary issues, and erectile
    dysfunction.

19
Associated Chemotherapy
  • Vinca alkaloids, taxanes, and platinum analogs
    are most commonly implicatedDose-limiting CIPN
  • Less commonly, high-dose ifosfamide, high-dose
    methotrexate, etoposide, procarbazine,
    cytarabine, suramin, bortezomib, thalidomide, and
    arsenic trioxide
  • CIPN may occur during or soon after chemotherapy
    administration.
  • CIPN may progress with increasing doses or worsen
    after some drugs have been discontinued.

20
Assessment
  • Grading tools are available to grade the
    toxicity.
  • Determine the level of functional impairment.
  • Focus on evaluating from the patients
    perspective (subjective data).

21
Assessment Tools
  • Semmes-Weinstein filaments for cutaneous touch
  • VibrationNerve conduction
  • Reflexes
  • Assessment of temperature
  • ProprioceptionRomberg test for balance
  • Sharp/dull sensationPinprick test
  • Gait assessmentWalking on heels and toes
  • Muscle strengthFrom no contraction to active
    movement against full resistance
  • Patient-reported symptoms

22
Medical Management of CIPN
  • Accurate assessment is essential!
  • Dose adjustment of chemotherapy
  • Pharmacologic interventions (effectiveness not
    yet established)
  • IV or oral calcium/magnesium
  • Glutathione
  • Supplemental vitamin E
  • Amifostine, glutamate, and glutamine
  • Xaliproden

23
Painful CIPN
  • Agents to decrease dysethetic pain
  • Anticonvulsants
  • Tricyclic antidepressants
  • Opioids
  • Topical agents

24
Patient Teaching
  • Self-report measures
  • Identify triggers
  • Self-care measures
  • Online educational sites

25
Nursing Considerations
  • Complex causes with few treatments
  • Goals should consider quality of life.
  • Nurses are an integral part of the team to help
    manage CIPN, especially with ongoing assessment.

26
Hyperglycemiamalglycemia
27
Diabetes Brief Overview
  • Characterized by high blood glucose levels
  • Also known as diabetes mellitus
  • Caused by defects in the bodys ability to
    produce and/or use insulin
  • Hormone needed to convert glucose (sugar,
    starches) into energy
  • Produced in the pancreas
  • Glucose buildup in the blood causes diabetic
    complications.
  • Types of diabetes type I, type II, gestational
  • Approximately 25.8 million people (gt 8 of the
    population) in the U.S. have diabetes.
  • Cancer survivors 8?18 report diabetes or
    prediabetes.

28
Potential Impact
  • Both diabetes and cancer are prevalent diseases.
  • Incidence is increasing globally for both.
  • Between 8?18 of patients with cancer have
    diabetes.
  • Diabetes and hypertension often coexist if so,
    these two conditions along with cancer need to be
    addressed when planning treatment and
    surveillance following treatment.
  • A link exists between type II diabetes and
    cancer, most likely due to sharing similar risk
    factors.
  • Drug interactions and contraindications are a
    possibility.
  • Exacerbation of symptoms related to diabetes may
    occur when certain cancer treatments are
    administered or when cancer progresses.

29
Impact Examples for Patients with Diabetes
  • Some cancer treatment regimens include
  • Corticosteroids and other drugs, affecting blood
    glucose levels.
  • Immunosuppressive agents, increasing the risk of
    poor wound healing and infection.
  • Agents that result in nausea, vomiting, and
    diarrhea, affecting dietary intake and blood
    glucose levels.
  • Agents causing peripheral neuropathy, increasing
    this complication of diabetes.
  • Kidney function may also be affected by both
    diseases and some cancer treatments.

30
Nursing Care Implications
  • Gather thorough health history data, including
    detailed information about conditions and
    medications. Update at each visit.
  • Assess baseline and monitor blood glucose closely
    before, during, and following treatment for those
    regimens potentially affecting diabetic control.
  • Assess and manage baseline and ongoing symptoms
    related to all conditions.
  • Assist with collaboration efforts between
    physicians treating both diabetes and cancer.
  • Promote diabetes self-management efforts enlist
    assistance from a diabetes educator and dietitian
    to assess and plan for any needed changes in
    exercise, weight control, and meal planning.

31
Steroid Use in Cancer
  • Therapeutic
  • As part of Chemotherapeutic regimen for leukemia
    ,lymphoma, myeloma
  • Treatment of Graft versus host disease (GVHD)
  • Therapeutic/Prophylactic
  • Prevention and treatment of chemotherapy induced
    nausea and vomiting

32
Steroid Use in Cancer
  • Prophylactic
  • Prevention of hypersensitivity reactions with
    certain chemotherapeutic agents such as the
    taxanes

33
Steroid Induced Malglycemia
  • Malglycemia
  • Hypoglycemia (blood glucose lt 70 mg/dl)
  • Hyperglycemia (blood glucose of 126 mg/dl or
    greater
  • Glycemic variability (standard deviation of two
    or more measurements of 29 mg/dl or greater)

34
Potential Impact of Malglycemia on Clinical
Outcomes In Hospitalized Patients
  • Increased risk of infection and sepsis
  • Increased mortality
  • Decreased survival
  • Increased length of stay
  • Increased Toxicities
  • Storey, S. Von Ah, D. (2012) Impact of
    malglycemia on clinical outcomes in hospitalized
    patients with cancer A review of the
    literature. Oncology Nursing Forum39(5),
    458-465.

35
Strategies for Glycemic Management in the
Hospitalized Patient
  • Diet
  • Physical activity
  • Medications
  • Sulfonylureas
  • Metformin
  • Thiazolidiones
  • Insulin
  • Basal-bolus insulin therapy

36
Malglycemia in the Non-Hospitalized Cancer Patient
  • Not as well studied
  • Caused by both therapeutic and prophylactic
    steroid use
  • Similar concerns with potential consequences
  • Impaired cellular repair
  • Increased clotting
  • Increased aggregation of platelets
  • Increased inflammation
  • Decreased ability to fight infection
  • Increased cellular proliferation
  • Increased mortality
  • De Vos-Schmidt, D., Dilworth, K. (2014).
    Management strategy for steroid-induced
    malglycemia during cancer treatment. Clinical
    Journal of Oncology Nursing 18(1), 41-44.

37
Management Strategies
  • Send patient to PCP or endocrinologist
  • One strategy developed by one oncology nurse and
    one diabetes nurse educator
  • All patients given corticosteroids screened with
    a 2 hr postprandial blood glucose on day 2 of the
    first chemotherapy cycle
  • Blood glucose lt140 mg/dl no interventions
    needed
  • Blood glucose 140-199 mg/dl Blood glucose meter
    and education on its use and dietary carbohydrate
    control
  • De Vos-Schmidt Dilsworth, 2014

38
Management Strategies
  • Blood glucose gt 200 mg/dl
  • Education about glucose monitoring, use of and
    insulin pen and dietary carbohydrate control
  • Blood glucose monitoring before each meal
  • Dietary carbohydrate control
  • Sliding scale insulin
  • De-Vos-Schmidt Dilworth, 2014

39
Hypertension
40
The Malignant Cell
  • Overexpression of EGFR1
  • Cell receives continuous signals to divide.
  • Daughter cells do not differentiate return to
    cell cycle to divide again.
  • Cell makes VEGF to stimulate angiogenesis.
  • Cell is signaled to ignore messages for apoptosis.

41
Angiogenesis
  • Process by which a tumor develops its own blood
    supply
  • Needed for the tumor to exceed 1 mm in diameter
  • Triggered by hypoxia, oncogenic signals, and
    pro-angiogenic growth factors
  • Growth of tumor and rate of spread are related to
    tumor vascularity.

42
Role of VEGF in Angiogenesis
  • Binds to receptors on the endothelial cells of
    nearby blood vessels
  • Sends message to increase production of more
    endothelial cells
  • Causes endothelial cells to migrate through
    basement membrane and toward the tumor
  • New blood vessel tube is formed.

43
Bevacizumab (Avastin)
  • Monoclonal antibody against VEGF
  • Activity in a variety of tumors including
    colorectal and brain
  • Toxicity profile
  • GI perforation
  • Delayed would healing
  • Arterial and venous thrombotic events
  • Bleeding/hemorrhage
  • Hypertension

44
Blood Pressure Classification
BP Classification SBP mmHg DBP mm Hg
Normal lt120 and lt80
Prehypertension 120-139 or 80-90
Stage 1 Hypertension 140-159 or 90-99
Stage 2 Hypertension 160 or 100
45
Management of BP for Adults
BP Classification Lifestyle Modification Initial Drug Therapy Without Compelling Indication Initial Drug Therapy With Compelling Indications
Normal Encourage
Prehypertension Yes No BP drug indicated Drug(s) for compelling indications
Stage 1 hypertension Yes Thiazide-type diuretics for most. May consider ACEI, ARB, BB, CCB, or combination Drug(s) for compelling indications
Stage 2 hypertension Yes Two-drug combination for most (usually thiazide-type diuretic and ACEI or ARB or BB or CCB) Other antihypertensive drugs as needed
46
Hypertension Glossary
  • Compelling indications other comorbid
    conditions that increase risk of heart disease.
    Treat patients with chronic kidney disease or
    diabetes to BP goal of lt130/80
  • ACEI Angiotension converting enzyme inhibitor
  • ARB Angiotension receptor blocker
  • BB Beta blocker
  • CCB Calcium channel blocker
  • National Heart, Lung and Blood Institute The
    Eighth Report of the Joint National Committee on
    Prevention, Detection, Evaluation, and Treatment
    of High Blood Pressure (JNC 8)

47
Survivorship Institute of Medicine Report
  • Establish survivorship as a distinct phase of
    care
  • Implement survivorship care plans

  • Build bridges between oncology and primary care
  • Develop and test models of care
  • Develop and evaluate clinical practice guidelines
  • Institute quality of survivorship measures
  • Strengthen professional education
  • Expand use of psychosocial and community support
    services
  • Invest in survivorship research
  • Executive Summary From Cancer Patient to Cancer
    Survivor Lost in Transition. Washington, D.C.
    The National Academies Press 2006.

48
Organ Toxicities
Due to damaging effects of drugs or treatment on
organ-specific normal cells
49
Late Effects
  • May appear months to years after treatment has
    ended
  • Include physical, psychological, and cognitive
    effects
  • Bones
  • Organs
  • Body tissues
  • Feelings
  • Moods
  • Actions
  • Post-traumatic stress disorder
  • Thinking
  • Memory
  • Learning
  • Concentration/attention span
  • Math, problem solving, handwriting, reading, and
    spelling
  • Planning and organizing
  • Processing

50
Fatigue
  • Affects almost 100 of patients undergoing cancer
    treatments
  • Most common and distressing symptom of cancer
    patients
  • Related to disease, biochemical imbalance,
    deconditioning, stress, treatment, quality of
    rest/sleep, nutrition, and functional status
  • Results in altered sleep patterns, depression,
    anxiety, and environmental factors
  • Can be lasting effect for weeks to months to
    years

51
Cardiac
  • Patients at risk
  • Radiation treatment in which the heart
    potentially received radiation
  • Radiation to a mediastinal mass in lymphoma
  • Radiation to breast, lung, esophagus
  • Early effects are pericarditis, pericardial
    effusion, tamponade
  • Late effects are valvular insufficiency,
    constrictive pericarditis, MI
  • Landier, W. Smith, S. (2011). Late effects of
    cancer treatment. In C. H. Yarbro, D. Wujcik
    B.H. Gobel (Eds.) Cancer Nursing Principles and
    Practice Seventh Edition. Sudbury, MA Jones and
    Bartlett Publishers

52
Cardiac
  • Chemotherapy/Targeted therapy
  • Anthracyclines (rubicin)
  • High dose cyclophosphamide
  • Trastuzumab
  • Many agents combined with anthracyclines
  • CHF and cardiomyopathy
  • 5-Fluoruracil and Capecitabine can cause acute
    coronary symptoms
  • Monitor EKG, Echo, MUGA
  • Landier Smith, 2011

53
Pulmonary
  • Radiation to the lung
  • Pneumonitis
  • Restrictive/obstructive lung disease
  • Chemotherapy
  • Bleomycin
  • Busulfan
  • Nitrosureas (BCNU)
  • Pulmonary fibrosis
  • Avoid high concentrations of oxygen in patients
    who have received these agents
  • Monitor PFT, CXR
  • Landier Smith, 2011

54
Neurological
  • Peripheral Persistent peripheral neuropathy,
    especially with paclitaxel
  • Monitor neuro exam
  • Neurocognitive many after chemotherapy complain
    of chemo brain and exhibit neurocognitive
    testing
  • Monitor neurocognitive testing
  • Landier Smith , 2011

55
Neurological
  • Central Nervous System
  • Neurosurgery
  • High doses of radiation to brain
  • Can have motor and sensory deficits, seizures,
    CVA, leukoencephalopathy
  • Auditory hearing loss with platinum
    chemotherapy
  • Ocular cataracts and glaucoma with
    corticosteroids
  • Monitor neuro, audiological and visual exam
    imaging as indicated
  • Landrier Story , 2011

56
Reproductive
  • In general the alkylating agents can cause
    infertility in men and women
  • In men, prostate cancer therapy (radiation or
    surgery) can cause impotence and incontinence
  • Androgen deprivation therapy (medical castration)
    can cause hypogonadism
  • Monitor FSH, testosterone
  • Landier Story, 2011

57
Reproductive
  • In women, pelvic irradiation may cause vaginal
    stenosis, uterine vascular insufficiency
  • Hormone therapy with tamoxifen, aromatase
    inhibitors, lupron may cause early menopause
  • Monitor FSH, LH, estradiol
  • Landrier Story, 2011

58
Gastrointestinal
  • With surgery or radiation may see adhesions,
    strictures, perforations, impaired absorption of
    nutrients, diarrhea, fecal incontinence, chronic
    enterocolitis, anorexia
  • May see impaired swallowing after head and neck
    irradiation
  • Monitor electrolytes, colonoscopy
  • Landrier Story , 2011

59
Liver
  • Treatment with antimetabolites or abdominal
    radiation can lead to hepatic dysfunction
  • Monitor LFTs, imaging as indicated
  • Landrier Story, 2011

60
GU
  • After bladder, prostate or spinal surgery may see
    incontinence, dysfunctional voiding, neurogenic
    bladder
  • Hemorrhagic cystitis after cyclopohosphamide
  • Monitor UA
  • Landrier Story , 2011

61
Renal
  • Chemotherapy
  • Platinum agents
  • Ifosfamide
  • Methotrexate
  • Nitrosureas
  • Symptoms
  • Glomerular toxicity
  • Tubular dysfunction
  • Renal insufficiency
  • Chronic kidney disease
  • Monitor renal function tests, UA
  • Landrier Story ,2011

62
Lymphatic
  • Radiation to the lymph node channel or lymph node
    dissections can result in lymphedema
  • Landrier Story ,2011

63
Musculoskeletal
  • Treatment with corticosteroids, androgen
    deprivation therapy, aromatase inhibitors,
    surgical castration, oopherectomy may result in
    osteopenia/osteonecrosis
  • Landrier Story , 2011

64
Dental
  • Xerostomia, dental caries and periodontal disease
    with radiation
  • Osteonecrosis with bisphosphonate therapy
  • Dental care as indicated
  • Landrier Story, 2011

65
Hematologic
  • Alkylating agents and other chemotheraeutic
    agents can cause myelodysplastic syndrome (MDS)
    and acute myelogenous leukemia (AML)
  • Monitor CBC
  • Landrier Story ,2011

66
Chronic Graft-Versus-Host Disease
  • Occurs 3?24 months after transplant
  • May involve skin, liver, eyes, mouth, upper
    respiratory tract, and esophagus
  • Erythematous skin rash is hallmark manifestation.
  • Cyclosporine and corticosteroids

67
Psychosocial
  • Depression
  • Anxiety
  • PTSD
  • Limitations in health care access
  • Alterations in body image
  • Psychosocial assessment
  • Landrier Story ,2011

68
Institute of Medicine Report
  • Establish survivorship as a distinct phase of
    care
  • Implement survivorship care plans

  • Build bridges between oncology and primary care
  • Develop and test models of care
  • Develop and evaluate clinical practice guidelines
  • Institute quality of survivorship measures
  • Strengthen professional education
  • Expand use of psychosocial and community support
    services
  • Invest in survivorship research
  • Executive Summary From Cancer Patient to Cancer
    Survivor Lost in Transition. Washington, D.C.
    The National Academies Press 2006.

69
References
  • American Diabetes Association. (2014). Diabetes
    basics. Retrieved from http//www.diabetes.org/dia
    betes-basics
  • Edgington, A., Morgan, M.A. (2010). Looking
    beyond recurrence Comorbidities in cancer
    survivorship. Clinical Journal of Oncology
    Nursing, 15, E3?E12.
  • Giovannucci, E., Harlan, D.M., Archer, M.C.,
    Bergenstal, R.M., Gapstur, S.M., Habel, L.A., . .
    . Yee, D. (2010). Diabetes and cancer Consensus
    report. Diabetes Care, 33, 1674?1685. Retrieved
    from http//care.diabetesjournals.org/content/33/7
    /1674.long
  • U.S. National Library of Medicine, MedlinePlus.
    (2014). Diabetes. Retrieved from
    http//www.nlm.nih.gov/medlineplus/diabetes.html
  • U.S. National Library of Medicine, PubMed Health
    A.D.A.M. Medical Encyclopedia. (2014). Diabetes.
    Retrieved from http//www.ncbi.nlm.nih.gov/pubmedh
    ealth/PMH0002194
  • Stevens, C., Dinkel, S., Catanzaro, J. (2011).
    The complex dual diagnosis of diabetes and
    cancer. Clinical Journal of Oncology Nursing,
    15(6), 654-658.

70
References
  • Biedrzycki, B.A. (2010). Peripheral neuropathy.
    In C.G. Brown (Ed.), A guide to oncology symptom
    management (pp. 405?421). Pittsburgh, PA
    Oncology Nursing Society.
  • De Vos-Schmidt, D. Dilsworth, K. (2014).
    Management strategy for steroid-induced
    malglycemia during cancer treatment. Clinical
    Journal of Oncology Nursing, 18,41-44.
  • Landrier, W. Smith, S. (2011). Late effects of
    cancer treatment. In C.H. Yarbro, D. Wujcik
    B.H. Gobel (Eds.), Cancer Nursing Principles
    and Practice (pp. 1755-1779). Sudbury, MA
    Jones and Bartlett Publishers.
  • National Heart, Lung, and Blood Institute (2014).
    The Eighth Report of the Joint National Committee
    on Prevention, Detection, Evaluation, and
    Treatment of High Blood Pressure (JNC 8).
  • Oncology Nursing Society. (2009). Putting
    evidence into practice Peripheral neuropathy.
    Retrieved from http//www.ons.org/Research/PEP/Pe
    ripheral
  • Storey, S. Von Ah, D. (2012). Impact of
    malglycemia on clinical outcomes in hospitalized
    patients with cancer A review of the
    literature. Oncology Nursing Forum, 39 (5),
    458-465.
  • Wickham, R. (2007). Chemotherapy-induced
    peripheral neuropathy A review and implications
    for oncology nursing practice. Clinical Journal
    of Oncology Nursing, 11, 361?376.

71
References
  • American Cancer Society. (2012). Cancer facts and
    figures. Retrieved from http//www.cancer.org/Rese
    arch/CancerFactsFigures/CancerFactsFigures/index
  • Eggert, J. (2010). Cancer biology. In J. Eggert
    (Ed.), Cancer basics. Pittsburgh, PA Oncology
    Nursing Society.
  • Van Gerpen, R. (2007). Pathophysiology. In M.E.
    Langhorne, J.S. Fulton, S.E. Otto (Eds.),
    Oncology nursing (5th ed., pp. 298?308). St.
    Louis, MO Mosby.

72
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