EFFECTS OF WHOLE BODY IRRADIATION ON MARROW
481
Table 4.—Classification of Mitoses 3.5 Years after Exposure,
Wright’s-stained Smears
Individuals
High dose group
A
B
C
D
E
No. of Mitoses
Counted
100
100
100
100
100
Mean values
Low dose group
F
G
H
100
100
100
Mean values
Normal comparisons
SAK
100
EPC
250
70
TMF
150
26
LEF
50
JFB
50
CRS
65
VPB
50
Meanvalues
Per Cent
Erythropoietic
Mitoses
Per Cent
Myelopoietic
Mitoses
Per Cent
Other
Mitoses
68
76
72
82
73
27
20
18
17
25
5
5
10
2
2
74.2
21.4
52
60
71
3T
38
23
61.0
32.7
6.3
72
67.6
62.8
75.3
77
64
64
77
68
27
28.4
243
20.7
19.2
4
30
18.4
32
1
4.0
12.0
4.0
3.8
2.0
6.0
46
0
69.7
26.0
4.2
4.8
ll
2
6
Per Cent
“Abnormal”
Mitoses
10
5
I
4
2
4.4
4
1
3
2.7
curred initially in a characteristic pattern and were clearly demonstrable
during the first 1-2 days after exposure, at a time whenthe cells of the peripheral blood did not show marked alterations, except for a progressive lymphopenia and possible granulocytosis. If the appearance of erythroblastic karyomeres is taken as evidence for a previous abnormal mitosis, then by 2 days
about 30 per cent of all nucleated red cell precursors of the persons exposed
to the high dose had emerged from an abnormal mitosis. Abnormalities of
mitoses were frequent during the first days (up to 50 per cent) and were
rare, although present (about 4 per cent), 3.5 years after the accident. Thus
it appears that the specific evaluation of marrow smears for cytologic abnor-
malities of patients exposed to ionizing radiation may be helpful in the assessmentof the clinical situation. The evaluation of cytologic changes in fixed
and stained marrow smears requires particular caution. Under normal conditions a marked variability of nuclear and cytoplasmic structure and staining
properties can be found. These may vary from area to area of one preparation and among smears and they depend in part on the technics employed.
Therefore, one should use only criteria that appear to be relatively independ-
ent of technical factors. It is believed that the M. C. Abn. shown in this
study are examples of such criteria and can be used successfully for a cytologic
evaluation of radiation effects. Less reliable are the nuclear and cytoplasmic