ESTIMATION OF ORGAN DOSES OF PATIENT UNDERGOING
HEPATIC CHEMOEMBOLIZATION PROCEDURES
William Jaramillo, Richard Kramer, Helen Khoury, Vinicius Saito
and Gustavo Andrade
Department of Nuclear Energy - Federal University of Pernambuco
Recife, Brazil
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Introduction
Hepatic chemoembolization
Previous studies
(maximum skin dose) Few organ doses studies?
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Organ doses conversion coefficients in IR
… if patient size is neglected when choosing DCC, the organ and effective dose
will be underestimated to an underweight patient and will be overestimated to an
overweight patient, with errors as large as 113% for certain projections.
Therefore, the use of phantoms with different body masses and/or heights for
the Monte Carlo calculations would certainly improve the organ and tissue
absorbed dose assessments for populations such as patients
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Objective
The aim of this study is to evaluate the organ and tissue absorbed doses as
well as radiation risks of patients undergoing hepatic chemoembolization
procedures performed in two hospitals in the city of Recife-Brazil.
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• Patients
50 hepatic chemoembolization procedures were investigated for 48
patients diagnosed with hepatocellular carcinoma which have been treated
in two hospitals in Recife Brazil.
Hospital A Hospital B
Methodology
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Methodology
• Data collection
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Methodology
• Calibration of KAP meters
𝑓 =𝐾𝑎 ∗ 𝐴𝑟𝑒𝑎
𝐾𝐴𝑃
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Conversion coefficients estimation
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Risk conversion coefficients assessment
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Results and discussion
Anthropometric data of the patients
Mean values of irradiation and dose parameters per hospital and gender for all
patients
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Conversion coefficients
HVL (mmAl)
Organ dose (mGy/Gy*cm2) 5,487 6,307 7,78 8,42 8,97
ADRENALS 1,141 1,113 1,407 1,283 1,398
BLADDER WALL 0,009 0,013 0,023 0,019 0,026
BRAIN *** *** 0,001 *** ***
ORAL MUCOSA 0,011 0,008 0,017 0,011 0,014
COLON WALL 0,194 0,19 0,27 0,237 0,263
BREASTS,glandular 0,148 0,118 0,195 0,153 0,178
KIDNEYS 1,398 1,298 1,615 1,481 1,555
LIVER 0,659 0,628 0,862 0,755 0,835
LUNGS 0,476 0,412 0,593 0,472 0,505
OESOPHAGUS 0,276 0,25 0,405 0,322 0,38
OVARIES *** *** 0,04 0,038 0,041
PANCREAS 0,544 0,521 0,748 0,656 0,745
SMALL INTESTINE WALL 0,238 0,237 0,345 0,295 0,333
SKIN ENTRANCE 7,2cm X 7,2cm 2,897 3,138 3,108 3,251 3,254
SPLEEN 0,224 0,196 0,313 0,244 0,278
STOMACH WALL 0,388 0,383 0,531 0,481 0,541
SALIVARY GLANDS 0,007 0,006 0,012 0,008 0,011
THYMUS 0,154 0,126 0,251 0,169 0,197
THYROID 0,024 0,028 0,051 0,037 0,041
EXTRATHORARCIC AIRWAYS 0,005 0,005 0,01 0,006 0,007
UTERUS 0,021 0,025 0,045 0,035 0,045
HEART WALL 0,411 0,348 0,582 0,43 0,478
LYMPHATIC NODES 0,243 0,215 0,331 0,259 0,287
GALL BLADDER WALL 0,335 0,348 0,474 0,446 0,488
SKELETON AVERAGE 0,557 0,545 0,655 0,616 0,633
MAXIMUM RBM ABSORBED DOSE 0,627 0,585 0,867 0,713 0,8
MAXIMUM BSC ABSORBED DOSE 0,877 0,823 1,239 1,014 1,105
WEIGHTED FASH DOSE 0,274 0,255 0,367 0,311 0,346
RISK OF CANCER INCIDENCE: CASES PER
100000/AKAP(Gy*cm**2) 0,981 1,996 1,797 1,840 2,65 RISK OF CANCER MORTALITY: CASES
PER 100000/AKAP(Gy*cm**2) 0,927 1,456 1,595 1,527 1,889
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Conversion coefficients
HVL (mmAl)
Organ dose (mGy/Gy*cm2) 5,487 6,307 7,78 8,42 8,97
ADRENALS 0,681 0,73 0,749 0,824 0,886
BLADDER WALL 0,011 0,011 0,016 0,027 0,028
ORAL MUCOSA *** 0,005 0,006 0,008 0,008
COLON WALL 0,137 0,127 0,144 0,174 0,183
BREASTS, glandular 0,067 0,081 0,051 0,062 0,076
KIDNEYS 0,907 0,947 0,904 0,948 0,988
LIVER 0,386 0,379 0,404 0,45 0,476
LUNGS 0,264 0,293 0,309 0,348 0,365
OESOPHAGUS 0,188 0,231 0,253 0,296 0,312
PANCREAS 0,359 0,394 0,395 0,436 0,468
SMALL INTESTINE WALL 0,159 0,161 0,18 0,213 0,227
SKIN ENTRANCE 7,2cm X 7,2cm 2,949 3,046 3,141 3,209 3,173
SPLEEN 0,128 0,146 0,159 0,197 0,21
STOMACH WALL 0,223 0,267 0,271 0,3 0,32
SALIVARY GLANDS *** *** 0,005 0,006 0,006
THYMUS 0,076 0,086 0,105 0,137 0,148
THYROID 0,018 0,021 0,029 0,04 0,043
EXTRATHORARCIC AIRWAYS *** 0,003 0,004 0,005 0,005
HEART WALL 0,211 0,235 0,26 0,318 0,334
LYMPHATIC NODES 0,155 0,151 0,161 0,204 0,218
GALL BLADDER WALL 0,207 0,237 0,24 0,275 0,282
SKELETON AVERAGE 0,39 0,387 0,386 0,44 0,446
MAXIMUM RBM ABSORBED DOSE 0,526 0,568 0,595 0,691 0,721
MAXIMUM BSC ABSORBED DOSE 0,739 0,805 0,848 0,979 1,017
WEIGHTED MASH DOSE 0,17 0,185 0,19 0,218 0,231
RISK OF CANCER INCIDENCE: CASES PER
100000/AKAP(Gy*cm**2) 0,873 1,126 0,744 1,118 1,349 RISK OF CANCER MORTALITY: CASES PER
100000/AKAP(Gy*cm**2) 0,751 0,876 0,692 0,966 1,101
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Calculated organ absorbed doses
Organs or tissues showing the highest doses are the skin, kidneys, adrenals,
liver, pancreas, and the skeletal tissues red bone marrow (RBM) and the bone
surface cells (BSC). X Congreso Regional Latinoamericano de Protección y seguridad Radiológica IRPA
Calculated organ absorbed doses
• Patient carried out more than one chemoembolization
• Heart absorbed dose = 498 mGy
• Absorbed dose thresold for circulatory disease to heart or brain≈ 0.5
Gy (ICRP, 2012)
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Risk assessment
Hospital A
Cancer incidence Cancer mortality
Gender Age Mass Height Images
Fluoroscopy
Time KAP
Cases per 105 per
KAP
Cases per 105 per
KAP
(y) (kg) (cm) Number (min) (Gy*cm2) 10-5 (Gy*cm2)-1 10-5 (Gy*cm2)-1
F 45 68 159 184 21.7 113.4 1.439 1.122
F 75 49 158 180 11.7 73.5 0.906 0.858
F 45 65 165 137 36 162.7 1.439 1.122
mean 55.0 60.7 160.7 167.0 23.1 116.5 1.261 1.034
M 70 49.7 156 218 11.2 131.4 0.760 0.695
M 64 66 171 323 47.1 193.9 0.896 0.788
M 70 81 168 354 31.2 731.1 0.576 0.533
M 72 53 160 176 25.8 139.0 0.696 0.649
M 35 81 169 362 14.3 235.8 0.841 0.663
M 65 53 165 139 12.3 187.1 0.862 0.759
M 72 49 162 128 14.2 65.4 0.696 0.649
M 63 73.7 166 176 12.6 186.7 0.765 0.665
M 62 69 163 206 26.9 319.8 0.783 0.676
mean 63.7 63.9 164.4 231.3 21.7 243.4 0.764 0.675
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Risk assessment
• Apart from the exposure conditions, especially the tube potential, and the
patients mass and height, risk CCs depend on gender and age. Radiological
cancer risks are higher for women than for men, mainly because of the
increased breast cancer risk, and are higher for younger patients.
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Conclusions
• In addition to reaching the thresholds for skin injuries to patients, other
important organs can receive significant radiation doses in hepatic
chemoembolization procedures compared with other diagnostic procedures.
• The results show that apart from irradiation parameters, such as tube voltage,
filtration, etc, organ and tissue absorbed doses depend aditionally on the
patient´s body mass. Organ and tissue absorbed doses increase with the
patient´s body mass.
• In this work, organ and tissue conversion coefficients for the air kerma–area
product for PA projection were calculated based on the anthropometric
characteristics of the patients for a range of beam qualities used in hepatic
chemoembolization interventional procedures that can serve to optimize
radiological protection of patients submitted to this medical procedure.
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Gracias por su atención!
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