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Understanding Cancer Development due to Radiation Exposure: a Comprehensive Overview

Dive deep into the late effects of radiation in relation to cancer development, exploring tumor growth, metastasis, oncogenes, risk estimation models, and more. Gain insights into the intricate mechanisms underlying radiation-induced carcinogenesis.

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Understanding Cancer Development due to Radiation Exposure: a Comprehensive Overview

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  1. Introduction to Radiation Health: Late Effects - Cancer Dr. Niel Wald

  2. Radiobiological Effects • Non-Stochastic • Severity varies with dose • May have threshold (cataract, dermatitis) • Stochastic • Probability of occurrence in population varies with dose • No threshold (cancer, genetic damage) 227-4

  3. Intracellular Effects of Radiation 138-A

  4. 395-4 Classification of Neoplasms

  5. Basis for Tumor Dose:Response Estimates 175-3

  6. Tumor Growth Curve 395-6

  7. Scheme for Induction of Cancer by Environmental Carcinogens Normal Cells Initiator(s) (electrophilic, mutagenic) Chemical or Radiation Carcinogen Initiated Cells Tumor Cells Promoter(s) Clones Inactive Metabolites Gross Tumors 395-11 Courtesy of Miller and Miller

  8. 395-1

  9. 395-2

  10. 395-3

  11. Three germ layers and the tissues derived from them 666-1

  12. Histogenetic classification of benign tumors 642-1

  13. Histogenetic classification of malignant tumors 642-2(1)

  14. Histogenetic Classification of Malignant Tumors with Atypical Nomenclature: 642-2(2)

  15. Mechanisms of Cell Death 642-3

  16. Cell Death (necrosis and apoptosis) 642-4

  17. Maturation Arrest 642-6

  18. Metastasis Formation 666-2

  19. Metastasis Formation 666-3

  20. Cancer Development 395-16

  21. General Properties of Initiating Agents & Promoting Agents *defined in a broad sense as agents that can both initiate cancer in limited dosages and induce cancer in higher dosages or in states of increased host susceptibility 395-15

  22. Properties of Oncogenes and Tumor Supressor Genes 666-9 * From Rudden, 1995b, with permission.

  23. International Leukemia Incidence 666-4

  24. Alternative Radiation Dose-Response Curves 227-5

  25. Cancer Summary • Tissues vary considerably with respect to their sensitivity to cancer induction. • The major sites of solid tumors induced by whole-body exposure to radiation are the breast, thyroid, lung and digestive organs. • Age, both at the time of exposure and diagnosis, is a very important variable relating to cancer induction. • The latency period (time from exposure to tumor detection) is frequently very long, i.e. years to decades. • Interaction between host and environmental factors (i.e., hormonal influences, exposure to other carcinogenic agents) may play a significant role in tumor induction. • Nearly all the tissues in the body are susceptible to tumor induction. • The dose-response relationships for many animal model systems are qualitatively similar to those for human tumor induction. However, direct quantitative risk extrapolation from animals to man would be inappropriate 395-28

  26. Radiation Cancer Risk Estimation 341-2

  27. Radiation-induced Cancer Risk 227-6

  28. Absolute Risk Model 220-4

  29. Relative Risk Model 220-5

  30. Dose-response Interpolation Curves 227-1

  31. Radiation Dose:Slope Relationships 227-2

  32. Radiation Dose Rate Ranges 227-3

  33. Hiroshima Dose:Distance Relationship 92-I

  34. ABCC Shielding History Floor Plan 93-C

  35. A-Bomb Leukemia Cases by Year 100-C

  36. A-Bomb Leukemia by Type and Dose 96-B

  37. A-Bomb Leukemia Dose-Response Curves 302-5

  38. A-Bomb Exposure Age vs.Leukemia Risk 220-2

  39. The quadratic risk coefficient () has increased, whereas the linear low-dose risk coefficient () has decreased, suggesting that currently accepted standards for low-level gamma exposures are not in need of revision on the basis of changes in data from Japan. Risk Coefficients for Leukemia Mortality Risk Coefficient 10 rad (Cases/106/year/rad)100 rad Source: Adapted from Straume and Dobson (1981). Reproduced from Health Physics, Vol. 44 by permission of the Health Physics Society 303-4

  40. The observed and expected numbers of Ankylosing Spondylitis deaths due to leukemia and aplastic anemia, 1935 - 54 study series Number of Deaths Significance of difference between observed and maximum expected number of deaths: Leukemia: P < 0.000001 Aplastic anemia: P < 0.000001 104-E

  41. Spondylitis: Leukemia Dose-Response 104-G

  42. Spondylitis: Leukemia Latency Postexposure 104-F

  43. Incidence of Death from Leukemia in Physicians 104-D

  44. Risk of Leukemia in various Diseases and Conditionsa,b a Risk of leukemia in various groups with specific epidemiologic and pathologic characteristics in populations followed for 10-30 years. b Leukemia risk (lifetime): Mortality increment from single exposure to 1 rad is 15-25 cases/106 persons or ~ 1/50,000. c Free in air doses (rads): gamma rays > 500 rads; neutrons > 60 rads Source: Modified from Miller (1970; from Brent (1980) 303-5

  45. Leukemia Risk 96-I

  46. A-Bomb: Mortality Relative Risks 173-1

  47. A-Bomb: Cancer Relative Risks 173-2

  48. A-Bomb: Cancer Dose-Response 173-3

  49. 668-29

  50. Thyroid Cancer Risk Associated with I-131 Exposure from Chernobyl Estimated Thyroid Dose from I-131 (Gy) Adapted from Astakhova et al., 1998 668-5

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