GOOD

1. Principles of Pediatric
Oncology
By: Gudeta D. MD
Moderator: Professor Amezene
September 2021

2. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Contents
►Brief history of pediatric oncology
►Epidemiology and survival statistics
►Importance of Pathology of Childhood Tumors
►Genetics of cancer
►Chemotherapy Principles
►Biologic Targeted Therapy
►Local tumor control
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3. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Introduction
►A number of milestones in the evolution of cancer therapy have come from the
field of pediatric oncology
» The first clear evidence of chemotherapy
» The first successful use of a multidisciplinary approach …Wilm’s tumor
 Cooperative research groups
» The successful use of a combination of chemotherapeutic agents …HL and ALL
» Models for molecular genetic research  individualized therapies
 Diagnosis, risk stratification, and treatment planning…
►Carefully developed multimodality therapy and multidisciplinary approach leads
to 80% improvement in survival over the last 30years
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4. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
History of Pediatric Oncology
►ALL  Aminopterin in 1948 by Farber and Diamond
►Methotrexate  produced cures for choriocarcinoma
►Multidrug regimens  improved response rates and response duration
» ALL  Wilm’s tumor ↓
» ⟹ Model for the successful use of multimodality therapy
►Adjuvant chemotherapy to control micro-metastases  substantial improvement
in survival
» Demonstrated in nonmetastatic osteosarcoma
↓
»  Standard practice for most solid tumors
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5. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
History of Pediatric Oncology
►Multidisciplinary cooperative groups  advanced care
» Children’s Cancer Group in 1955
» Children’s Oncology Group, COG in 2000
 Coordinate large cooperative studies across institutions and countries
►Chemotherapy regimens with dose- intensive programs have developed with advanced
supportive care
►Non-cytotoxic biologic therapies have developed recently
►Improvement in DNA sequencing techniques personalized medicine
►Improvements in radiation therapies
►Dramatic improvements in survival and quality of life for children with solid tumors
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6. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Epidemiology and Survival Statistics
►Childhood cancer accounts for only 2% of all reported cancer cases
►It accounts for 10% of all deaths among children
 Mortality has declined by 66% since 1970s
 5-year survival rates have improved by 25% since 1970s
►The incidence for specific cancers vary by  age, gender, and race
►Bimodal age distribution  before 2 years & during adolescence
 < 2years CNS malignancies, neuroblastoma, AML, Wilms tumor, and
retinoblastoma
 2-4yrs  ALL
 >9 years HL, osteosarcoma, and Ewing sarcoma
►Overall incidence = 16.2 per 100,000 children/year
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7. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Tumor Biology-- Signal Transduction
►Signal transduction pathways regulate all aspects of cell function
►Extracellular signals
» Signaling mediators  membrane-bound receptors, TKs⬇
» Effector cells  second messengers—proteins ⬇
» Expression or silencing of genes encoding proteins involved in all aspects of cellular
physiology
►Integration of multiple extracellular and intracellular signals determines the
response of a cell to competing and complementary signals  proliferation or
quiescence
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8. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Tumor Biology
►During normal cellular development and renewal, cells evolve to perform highly
specialized functions
» Under strict checks and balances
 TP53, RB proteins
►Cancer is a genetic disease
» Triggered by accumulating genetic and epigenetic changes influenced by hereditary
factors and the somatic environment
» Inactivation of the effectors of cell-cycle regulation or the bypassing of cell-cycle
checkpoints  dysregulation of the cell cycle, a hallmark of malignancy
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9. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Tumor Biology:
Understanding Childhood Cancer and Treatment Principles
►Genetic alterations
» Activation of an oncogene or loss of a tumor suppressor gene non-response to growth
regulators
►Advent of sophisticated gene sequencing techniques  identification of very
specific genetic alterations
► Understanding the specific characteristics of an individual tumor
►Individualized Rx regimen vs generic standardized protocols
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10. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Cancer Cytogenetics
►The association of a consistent chromosomal aberration with a specific cancer
was first made in 1960 with the discovery of the minute “Philadelphia
chromosome” in CML
» (9;22) (q34;q11)
►Identification of sub-chromosomal deletions, inversions, and translocations 
identification of oncogenes and tumor suppressor genes
►Consistent chromosomal aberration with specific tumor
» Diagnostic and prognostic information
 E.g.  Risk stratification of Wilm’s tumor based on tumor characteristics
 E.g.  The poor prognostic signs in neuroblastoma…
►Rapidly expanding array of genetic data on individual tumors  personalized
Rx regimen
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11. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Tumor Imaging
►Imaging has several important roles in the management of childhood cancer:
» Diagnosis
» Staging of disease
 Assessing the local extent, possible resectability and identifying metastases
» Providing image guidance for biopsy
» Monitoring treatment and complications
» Surveillance imaging detecting recurrent disease
►Precautions in children
» Need for sedation or other distractions
» Concern for ionizing radiation exposure  second malignancy
» Contrast related organ toxicities
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12. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Importance of Pathology In Childhood Tumors
►Less than 10% of solid tumors are epithelial in children
►Exact diagnosis is more difficult in children because of :
» The prevalence of small round blue cell tumors
» Lack morphologically distinguishing characteristics
►Exact diagnosis is crucial in pediatric cancer
» To define the prognostic subgroups
» For dose intensive therapy intended for cure
►Diagnosis depends on
» An adequate quantity and quality of tissue?
 Discussed with the surgeon, pathologist, and pediatric oncologist before the procedure
» Available pathologic tools, specimen handling
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13. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Importance of Pathology In Childhood Tumors
►The role of the pathologist goes beyond providing histological diagnosis
►Pathological diagnosis is a clinical opinion based on the interpretation of
histological findings in the light of clinical details provided
» it is not just a result
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14. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Chemotherapy Principles in Pediatric Oncology
►The goal  To maximize tumor kill while maintaining acceptable side
effects
►Clinical trials  Development of standard combination chemotherapy
regimens
» Remains the mainstay of the medical treatment of childhood cancer since 1960s*, ALL
►Development phases in clinical trials
» Phase I dose-escalation to determine the maximally tolerated dose
» Phase II To explore the efficacy and establish spectrum of activity
» Phase III  Compare established effective chemotherapy combinations with new regimen
►Principle of designing combination chemotherapy
» Use agents with different mechanism of action and non-overlapping toxicities
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15. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Principles of Adjuvant and Neoadjuvant
Chemotherapy
►Micro-metastatic disease  exists at the time of presentation for clinically
nonmetastatic disease
»⬇Study on sarcomas, lymphoma.. only 20% were cured by resection/surgery alone
►Adjuvant chemotherapy
» The goal is to prevent the appearance of metastatic disease
» Should be given with in 2 weeks of initial surgery
►Neoadjuvant chemotherapy
» Started as soon as the diagnosis is established… Standard in EWS and osteosarcoma
 Minimize the development of chemotherapy resistance???
» Delayed surgical resection  allow more complete and less morbid resection
» Helpful in instituting individualized regimen
» Beneficial only for tumors for which a known highly effective combination chemotherapy
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16. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Chemotherapy Dose Intensity
►Chemotherapy agents have a sigmoidal Dose- response curve.png
►Effective combination chemotherapy
» The correct combination + the correct dose of each agent
►Dose Intensity is the amount of drug delivered per unit time, mg/𝒎𝟐/week
►Dose intensity is increased  with the goal of maximizing efficacy
» Administer the maximal tolerated dose in the shortest possible interval while
maintaining tolerable toxicity
» Agents with limited organ toxicity
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17. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Chemotherapy Dose Intensity
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18. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Chemotherapy Dose Intensity
►Dose intensity can be increased by increasing the doses and/or the
frequency
►Decreasing or increasing dose intensity has significant effect in relapse or DFS
rates
 Demonstrated in animal studies as well as prospective clinical trials
• Cyclophosphamide
• ALL ---less than 94% of planned dose  5-fold increase risk of relapse
►Dose intensive trials in pediatrics  with advances in supportive care for
toxicities
 G-CSF, IL-11, PBPCs, …myeloablative chemotherapy +/- total body irradiation
 Cardioprotective agents … Dexrazoxane
►Dose intensity  depends on risk stratification of patients
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19. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Chemotherapeutic Agents
►The rational design of combination chemotherapy programs requires
an understanding
» The mechanism of action
  Non-selective interference with DNA or RNA synthesis,
transcription, or repair
» The site of metabolism
» Rate of drug clearance
» Toxicity profile for each drug
►Understanding the individual mechanisms of action helps in the design of drug
combinations with additive or synergistic antitumor effects
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►Base on their mechanism of action chemotherapeutic agents
are divided into different classes:
» Alkylating agents… (cisplatin and its analogs)
» Antimetabolites …(Methotrexate, 5-FU, Cytarabine…)
» Topoisomerase inhibitors …(Doxorubicin, Etoposide…)
» Anti-microtubule agents …(Vincristine, Paclitaxel…)
» Differentiation agents …(Tretinoin…)
» Miscellaneous non classified agents  steroids (Prednisolone), bleomycin…
» Biologic agents …(Imatinib, sorafenib…)

20. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Acute Chemotherapy Toxicity
►Most acute toxicities are reversible
►Toxicity is greatest in the normal cells with the highest rate of turnover
» Bone marrow cells, mucosal lining cells, liver cells, and hair cells
►The most common side effects of combination chemotherapy are:
» Nausea and vomiting, mucositis, diarrhea
» Myelosuppression, hair loss,, LFT abnormalities, and allergic reactions
►Myelosuppression
» An expected side effect of almost every treatment program for childhood solid tumors
» Require frequent transfusions
» Neutropenia  life-threatening bacterial or fungal infections
 In 75% of dose-intensive regimens  20% bacteremia
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21. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Acute Chemotherapy Toxicity
►Agent specific side effects
» Vincristine and doxorubicin  vesicants
  severe skin and tissue necrosis if extravasate into the SC tissue
» Doxorubicin and related anthracyclines  have cumulative cardiotoxic effects
» Cisplatin and ifosfamide  each have toxic renal effects
 Often combined for osteosarcoma and neuroblastoma
≈ Fanconi syndrome (renal electrolyte wasting)
» Cisplatin  hearing loss (at high doses)
» Vincristine and vinblastine  cumulative peripheral neuropathies
►Agents toxicities must be considered when designing therapeutic programs
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22. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Acute Toxicity Supportive Care
►Some of the success in improving outcomes for children with cancer is attributable to
advances made in supportive care
►Routine use of hematopoietic growth factors
» G-CSF  rapid granulocyte recovery and shorter hospitalizations for fever and
neutropenia
» IL-11  enhances platelet recovery, GI ‘rescue’
►Renal toxicity
» Renal tubular damage from cisplatin  reversible
» Fanconi syndrome hyperhydration and forced diuresis
►Amifostine  Show promise in preventing cisplatin-induced renal injury
» Have protective effects against neurologic and cumulative bone marrow
toxicities
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23. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Long-term Side Effects of Cancer Therapy In
Children
►1 of every 900 adults is a survivor of childhood cancer
►Acute toxicities tissues with the highest cell-turnover rate
►Long –term effects  Slow/non-regenerating tissues
» Growth, fertility, and neuropsychological development problems
» Radiation therapy
  Inhibit further growth of bone, muscle, heart, and kidney within the radiation field
  Affect fertility
►The effects are more pronounced with combined-modality treatment
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24. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Long-term Side Effects of Cancer Therapy In
Children
►Growth retardation  unique to children
» Depends on dose and the age at the time of therapy
» Cranial irradiation can lead to GH deficiency  result in poor linear growth
unless GH replacement is given.
 50% will have adult height < the fifth percentile
» Total-body or spinal irradiation  Will not achieve their full height potential
even with GH stimulation
►Musculoskeletal problems:
» Scoliosis, avascular necrosis, osteoporosis
» Atrophy or hypoplasia of tissues (jaw, orbit, or neck)
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25. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Long-term Side Effects of Cancer Therapy In
Children
►Cardiotoxicity  cardiac muscle damage  CHF
 Increased CV late effects stroke, blood clots, and angina-like symptoms
» From anthracycline in the treatment of Ewing sarcoma, osteosarcoma, and lymphomas
» Prevention
 Continuous-infusion anthracyclines
 Cardio-protectant dexrazoxane
 Limit the cumulative lifetime dose of anthracyclines to 450 mg/𝑴𝟐
►Pulmonary Fibrosis  decreased Lung volume, compliance and diffusing capacity
» Nitrosoureas and bleomycin are known agents to cause pulmonary fibrosis
►Hypothyroidism  after radiation in HL
►CRF (cisplatin), Chronic cystitis (cyclophosphamide )
►Prolonged hypogammaglobulinemia and T-lymphocyte dysfunction
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26. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Long-term Side Effects of Cancer Therapy In
Children
►Secondary malignancy
» Over all ~5% at 25 years after diagnosis
» Highest in patients who received both chemotherapy and radiation therapy
 HL survivors have the highest secondary malignancy rates 7% at
15years
≈ Even higher in recurrent HL cases
►The most common secondary malignancies are:
 Breast cancer  35% at 40years
 Leukemia, AML  Etoposide with latency of 1-3years
 NHL
 Thyroid carcinoma
 Secondary osteosarcoma within the radiation field for STS, RB, EWS
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27. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Biologic Targeted Therapy
►Advances in understanding of key genetic events in carcinogenesis 
development of new agents that act on biologic pathways
►Biologic agents vs cytotoxic agents
» Their optimal therapeutic dose is below the maximal tolerated dose
» The challenge
 Optimal dose, how to combine with cytotoxic agents, clinical response validation yet
to be determined
►These agents include:
» Signal transduction inhibitors
 Tissue GFR inhibitors, anti-angiogenesis agents, and biologic response modifiers
» Individual cytokines
» Tumor-targeted antibody therapies and
» Adoptive immunotherapy techniques
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28. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
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29. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Biologic …Signal Transduction Inhibitors
►Cellular signaling is a basic biologic function of all cells,
controlling cellular proliferation, differentiation, death
» Extracellular (e.g., GFR tyrosine kinase) ---Imatinib
» Intracellular effector and survival pathways (e.g., RAS, RAF, FAS, BCL-2)
►STIs restore cell function by Blocking aberrant signal transduction pathways
that leads to development of tumor
►1. Anti-angiogenesis agents proposed in the 1970s
» Affect both intracellular and extracellular pathways
» E.g. Bevacizumab  anti-VEGF antibody
 Sensitize endothelial cells to cytotoxic cell death
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30. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Biologic …Signal Transduction Inhibitors
►2. Biologic Response Modifiers ⇄ Immunotherapy
» The goal is to stimulate the immune system to help eradicate tumors
 By improving the immunogenicity of a tumor
» Are malignant cells foreign cells?
» Cytotoxic T-lymphocytes
 Directly cell lysis through cytotoxic granule release or
programmed cell death
 Indirectly
≈ Helper T-cells  Cytokines  APCs
≈ Tumor selective effector cells ADCC
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31. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Immunotherapy
►1. Adoptive Immunotherapy
» Use of tumor vaccines made from autologous or allogeneic tumor-associated
antigens
 Specific purified tumor antigens can be made more immunogenic by attachment to carrier
proteins (adjuvants)… Melanoma trials
 Stimulating tumor-specific T-cell immunity to modified tumor peptides  generate
cytotoxic T-lymphocytes
≈ Neuroblastoma murine tumor cells  enhanced tumor presentation  potent in vivo tumor
response
» Genetically engineering tumor cells to overexpress cytokines
 GM-CSF, IL-2, IL-12, IL-1α  activate APCs and effector cells
» Use of cytokine infusions to stimulate immune reaction against tumor cells
 INF-α, IL-2, and TNF
►2. Tumor-targeted Antibody Therapy
» Recombinant chimeric human/mouse antibodies
 Anti-CD20 Rituximab (Genentech, Inc., San Francisco, CA)
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32. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Local Tumor Control
►Control of local disease is critical to favorable outcomes in pediatric oncology
►Metastatic disease is more readily eradicated in young patients than in adults
when the primary lesion has been adequately treated
►Local control is achieved with surgical resection and/or radiation therapy
►Radiation therapy
» Use of ionizing radiation to control malignant cells
» Plays an important role in the treatment of numerous pediatric tumors
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33. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Radiation Therapy
►Mechanisms of action
» 1. Direct impact on DNA  impaired cell division
» 2. Indirectly by producing reactive free radicals  major route
►How does radiation therapy works?  causes sublethal damage to cells
» The difference lies in the ability to repair the damage b/n normal and malignant cells
►The effect ionizing radiation depends on
» The number of actively reproducing tumor cells at the time of exposure
» The length of the cell cycle  delayed effect
» Dose fractionation
 Allows normal cells to recover while having a cumulative effect on tumor cells
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34. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Radiation Therapy Effects
►The goal in radiation therapy
» To deliver the highest effective dose with minimal exposure to surrounding normal
structures
►Acute reactions to ionizing radiation depend the balance between replication
and cell death
» Minimized by increasing intervals between dose fractions
 Allow enhanced cellular repopulation and recovery
►Long-term effects of therapy
» Depend primarily on the total exposure dose and the size of each treatment
fraction
» Minimized by lowering the dose per fraction and increasing the number
of fractions
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35. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Radiation Therapy
►Timing of radiation therapy
►Preoperative radiation therapy
» Smaller treatment area
» Reduce the tumor volume for complete resection
» Potential tumor seeding during operative removal may be reduced
» Delays surgical intervention
►Postoperative radiation therapy
» Many combined strategies use this approach  STS
 Treatment fields and doses are determined after surgical resection and histologic assessment
 Higher doses can be delivered postoperatively when the target volumes have been more accurately
defined
 Doses to the periphery of the tumor can be finetuned
 Require a wider treatment area
►Intraoperative radiation therapy
►Definitive radiation therapy
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36. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Radiation Therapy
►Radiation therapy in children
» Several aspects need to considered
 Use of sedation to avoid inappropriate exposure of surrounding tissues
 Developing organs
≈ Use lower treatment doses and accept a higher recurrence rate
 Long-term effects of combined-modality therapy must be considered
►Different techniques of delivering safe, efficacious doses of radiation have
developed
» Brachytherapy
» Intraoperative Radiation therapy, IORT
» Intensity-Modulated Radiation Therapy, IMRT
» Proton therapy? Part of ongoing COG trials
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37. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Innovative Adjunctive Techniques
►Cryosurgery
» In situ destruction of tissue by the freeze/thaw process
» The goal is to devitalize a neoplastic tissue by freezing  rapid freezing, slow thawing
» Uses liquid nitrogen at the tip of the cryoprobe, at temperatures range of −160° to −180°C
►Radiofrequency Ablation, RFA
» Use of thermal energy to cause coagulation necrosis of the target tissue
» Use in pediatrics is anecdotal
►Chemoembolization
» Regional delivery of chemotherapy for hepatic tumors
 Infusing the agent distal to a ligated hepatic artery
» Experience in pediatrics is limited
 In persistent, unresectable, or recurrent hepatoblastoma
 In nonmetastatic hepatocellular carcinoma
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38. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Innovative Adjunctive Techniques
►Lymphatic Mapping
» Accurate staging of regional disease is critical in managing malignancies
» Mapping draining sentinel LNs uses:
  radiolabeled sulfur, colorant dye and mapping with gamma robe
» Mainly for Melanoma and breast cancer in adults and for RMS in pediatrics
» For RMS  Intergroup RMS Studies I, II, III
 Lymphatic mapping  detection of ~ 40% positive sentinel LNs (blue staining)
 The technique :
≈ 0.2– 0.5 mL of 99Tc sulfur colloid is injected around the tumor a day before the surgery
≈ 0.5–1 mL of vital blue dye is injected immediately before surgery
≈ LN identification with a hand-held gamma probe
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Pediatric
Oncology
Friday,
February
23,
2024

39. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
References
►Holcomb and Ashcrafts pediatric surgery 7th,2019
►Principles and practice of pediatric oncology, 7th ed. philip. A. Pizzo
►Coran principles of pediatrics surgery 7th,2012
►Pediatric Cancer Diagnosis, Therapy, and Prognosis: M.A. Hayat 2015
40
Principles
of
Pediatric
Oncology
Friday,
February
23,
2024

40. ADDIS ABABA UNIVERSITY COLLEGE OF HEALTH SCIENCE, DEPARTMENT OF SURGERY,
PEDIATRIC SURGERY UNIT
Thank you
Principles
of
Pediatric
Oncology
Friday,
February
23,
2024
41