TABLE 37. _ Lymph Oncan Distrinution oF #?Th 1n Man FoLLowIneG INTRAVASCULAR ADMINISTRATION OF THOROTRAST Author... -. 02ers ee eee Hurshet al.(@) nodes Kaul Rundo ANL group Parret al. 9 6 3 11, 17 This paper 4 Several 9 2 6 Duration .....-.-..255- 17d-19y Long term Long term (mean 12y) 18y, 26.5y 26d-26y Method of analysis. ..... comity analysis analysis @-ray analysis analysis Reference... 1s. seen ee _—-——_—— Kev of caseS.-- 6... ee eee ~ 3 960 Mean values fcolumns 2-6) Fraction of body burden in organ :‘¢) 10041/144,7 percent —_——— fi ————f ' Liver spleen Red bone marrow Lung skeleton Adrenal Heart Intestine Kidney —_ Muscle Pancreas Thyroid 100 9 8 1.8 0.75 0.003 0.07 0.6 (52)) 100 (17) 33 (30) (0.8) 58 (71)® (17) (<12) 1.2 100 36 100 <17 (0.55) © 0.8) 0.18 100 18 11 ' 0.4 4.1 0.13 5 0.05 0.05 Total 100 24 12) 1.1 1.7 0.003 0.07 0.6 0.15 5 0.05 0.05 144.7 69 17 8 0.8 1.2 0.0029 0.05 0.4¢° 0.1 3,5 0.0366 0.03) 100 “ Liver, spleen, red bone marrow and lung figures are from authors’ ‘‘preferred values” for 3?Th concentrations in these organs, based on 4 patients (17d, 49d, 18y and 19y burdens). Other figures are based directly on quoted #2Th concentrations (18 and 19y simplest’ burdens). Organ weights in standard man assumed. imes thee ‘” Quoted distribution as percent of whole-body burden. erties off (? Normalized with respect to the liver content assuming liver burden to be 70% of whole-body burden. “) Weighted mean value, using weighting factor of 0.1 for results of Rundo and Kaul, which were not based directly on measure- is paper.fr ‘nts of separated red bone marrow, and unit weighting factor otherwise. she basis: " Excluding organs not listed (particularly lymph nodes and perivascular deposits, which may contain a significant fraction fof the injected Thorotrast). ‘8 Measurements to be interpreted with caution as they are based on only a single analysis. tion of °8°Th among the various organsof the body, so revealed (Table 36) is in general agreement with the can be made on itions inresults of other workers. A comparison i acentraedth basis of the data presented in Table 37, where, as n Tablet for Table 35, normalized values relative to the conre 2827,RCCNtration in the liver, are quoted. The results sugthe ma-feC"! that the major part of the Thorotrast (~95% of y, some thet contained in the organslisted) is taken up by the olations £20" !oendothelial system, and that it is distributed between the liver, spleen, and bone marrow, approxi> due tok an, Un ma.‘tely in the ratios 100:24:12. sample} It is important to note that the percentage values larly in fisted i3 n Table 37, last column, refer only to those orin thet Bins listed, and notably they neglect any considera- s basis, jtion of the lymph nodes. Reliable data for the lym- rat are Pltic system are almost completely lacking, but the - factivities quoted for patient 166 (Table 35) suggest 35) tof thet theTh concentration in certain lymph nodes , organ B' ¢xcced that in the liver by approximately a factor ith the 0 0. It would be not surprising, therefore, if a sig- istribu- Mic“tnt proportion of the whole-body burden of 73?Th were to be found located in the whole lymphatic sys- tem. Consideration has also been omitted from Table 37 of the activities located in perivascular deposits at the site of the injection. Such deposits are indicative of a poor injection technique. External measurements of Thorotrast patients in Vienna by whole-body profile scanning have shown that the proportion of the total- body radioactivity (of *°°T1) so located, not uncommonly exceeds 50%. The perivascular deposits deserve a separate study. Considerable caution is called for when using the re- sults of Table 37 to predict the distribution of *8?Th in any one Thorotrast patient. Particularly for the liver and spleen, wide departures from these average values —showing no obvious correlations with variables such as the age of the burden—are commonly observed in individual cases. This is evident from the data of Table 35, though undoubtedly here, sampling problems were partly responsible. However,it is also certain that real differences exist. Thus, in a series of 15 patients,