Radiation and cancer

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Radiation and cancer by Dr Rangarajan

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Radiation and cancer

  1. 1. RADIATION & CANCER Dr V. Rangarajan Head, Dept. of Bio-Imaging Unit Tata Memorial Hospital Mumbai , India
  2. 2. Radiation and Tolerance
  3. 3. Medical uses of radiation - DiagnosticAlmost all imaging tests use radiationX-rays, CT scans, angiograms etcWorldwide, approximately 330 radiologicalexaminations are done per 1000 populationExtremely useful for diagnosis of most diseasesincluding cancerRadio-isotopes : Bones scan, PET Scan, Perfusion scans
  4. 4. Radiation & Cancer Outcome• Uterine Cervical Cancer > 90% survival• Laryngeal Cancer > 95% survival• Ewing’s sarcoma & Hodgkin’s lymphoma melt away with radiotherapy• Radiotherapy improves cure rates by 30% when added to Surgery & Chemotherapy
  5. 5. Radiation : Stochastic (Linear, Cumulative & no Threshold)• Natural radiation occurs from various sources – Earth, soil – Outer space• Nuclear power plants and health issues – Cancer – Congenital anomalies – Accidents
  6. 6. Radiation & Cancer• Highest incidence in the north east• No nuclear reactors in these states• Incidence in Mumbai, Chennai, Bangalore, Ahmadabad and Delhi (cities with one or more nuclear reactors) – similar to other metropolitan cities with no reactors
  7. 7. Cancer incidence in IndiaAreas with no Areas with 1/morenuclear reactors nuclear reactors
  8. 8. Karunagapally - Kerala• High natural radiation• Thorium sands• Study conducted by Regional Cancer Centre, Trivandrum
  9. 9. Jayalekshmi P et al. High natural radiation and cancer in Karunagapally, Kerala
  10. 10. Eldorado (Canada) Uranium workers• 17660 uranium workers followed for several  decades• Compared with general Canadian population• Lower mortality rates from all causes and all  cancers• Lower incidence of cancers• “healthy worker” effect? Lane RS et al. Radiation Res 2010; Oct 4
  11. 11. French nuclear power plants• Study conducted in 20 km radius of 29 nuclear installations in France• Incidence rates comparable to national incidence rates as reference (cancer, cong. Anomalies, sterility)• No increase in childhood Leukemia seen Laurier D et al. J Radiol Prot. 2008 September ; 28(3): 401–403
  12. 12. Finnish nuclear power plants• Three approaches – ecological analysis at municipality level – residential cohorts defined from census data – case-control analysis with individual residential histories• Compared to normal Finnish population• No increase in childhood leukemia or other cancers in areas next to the Finnish power plants Heinevaara S et al. Cancer Causes Control. 2010 April; 21(4): 587–595
  13. 13. Finnish nuclear power plants - 2• 15,619 Finnish nuclear reactor workers studied• No increase in cancer incidence• No association between cancer incidence and cumulative radiation dose Auvinen A et al. J Occup Environ Med 2002 Jul;44(7):634-8
  14. 14. Radiation exposure in Taiwan• A Co-60 source was mixed in metal scrap, melted and drawn into steel bars which were used in the construction of 1700 apartments for about 10,000 residents in 1982-84.• Residents were irradiated at least for 9 years, some up to 20 years• Annual dose in the first year 1983 was from about 50 mSv/y, up to 600 mSv/y• Total averaged dose started at 0.4 Sv, and went up to 6 Sv. Luan YC, et al. The true health effects of radiation
  15. 15. Taiwan – observed vs expected cancer deaths180160140120100 80 60 Mortality of public Mortality of irradiated id t 40 20 0 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 2000 2001 2002 year Luan YC, et al. The true health effects of radiation
  16. 16. Taiwan incident - conclusions• Chronic radiation exposure may actually be  beneficial to humans• Lower incidence of cancers compared to  expected• Lower incidence of congenital anomalies  compared to expected. Luan YC, et al. The true health effects of radiation
  17. 17. ACCIDENTS
  18. 18. ACCIDENTS ACCIDENTS : FACTS Category Fukushima Daiichi Chernobyl A UN report places the total confirmed deathsRelated deaths No deaths so far due to radiation from radiation at 64 as of 2008. Disputes continue about how many will eventually die Among the residents of Belarus, the Russian Federation and Ukraine, there had been up to the year 2005 more than 6,000 cases of thyroid Not yet known, but risks to human healthLong-term health damage cancer reported in children and adolescents who are thought to be low were exposed at the time of the accident, and more cases can be expected during the next decades Officials say radiation leaks are continuing and could eventually exceed those at The damaged reactor is now encased in aCurrent status Chernobyl. The priority is restoring concrete shell. A new containment structure is adequate coolant to the fuel ponds and the due to be completed by 2014 reactors themselves
  19. 19. Why tame the Nuclear Power?• Enslave technology to serve immortality• We tame technology to improve – quality of life – Ratio of benefit to risk
  20. 20. 90 A 80 B Life Expectancy (Years)GDP (US$/ Capita) 10000 70 60 50 1000 40 2 GDP=3.18-0.296(EA)+0.148(EA) LE =37+43/(1+exp(5.0-0.88*ln(EA ))) 30 10 100 1000 10000 10 100 1000 10000 Electricity Av ailability (Kwh/Capita) Electricity Av ailability (Kwh/Capita) 8 1.0 C D 0.8 6 Fertility (Number) HDI (Number) 0.6 4 0.4 2 0.2 F=1.2+8.5/(1+exp(-3.13+0.65*ln(EA))) HDI=0.31+0.69/(1+exp(4.7-0.74*ln(EA))) 0 10 100 1000 10000 10 100 1000 10000 Electricity Av ailability (Kwh/Capita) Electricity Av ailability (Kwh/Capita) Figure 5. Correlation amongst Human Development Indicators Continuous lines are the anlytical fits for the scatter plots. Fit expressions are giv en near the X axis.
  21. 21. Worldwide Severe Accidents, Aggregate Fatalities and Normalized Fatalities for all Energy Options during 1969-2000* Energy Chain No. of  Total  Normalised Accidents Fatalities Fatalities (per GWa) Coal‐global 1221 25107 0.876 Coal with China excluded 177 7090 0.690 Oil 397 20283 0.436 Natural Gas 125 1978 0.093 Hydro 11 29938 4.265 *Hydro‐2 10 3938 0.561 Nuclear 1 33 0.06**
  22. 22. Nagasaki Before and after
  23. 23. Nagasaki Hypocenter
  24. 24. Chernobyl : Now
  25. 25. Thank you

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