adults), another interpretation of Fig. 4 is that
‘the time for development of adenomatous
nodules following radiation exposure varies
directly with age at exposure.
The cumulative experience of benign plus
malignant nodule developmentas a function of
age at exposure showsclearly the increased
susceptibility of the younger population to
nodule induction (Fig. 3). Most benign nodules
and all the thyroid carcinomas have occurred in
females. It was noted (Robbins and Adams,
1989) that the prevalence of thyroid carcinomas
compared to benign nodules (15%) was lower
than that reported following medical x-ray
therapy (about 30%).
|
|
:
RONGELAP = SiFO
20 F
| ace |
1 IN. |
| 1954 |
h<1oyR
Nonthyroidal tumors
During the period 1985 through 1987, deaths
attributable to cancer occurred in three exposed
persons, all from Utirik. The types of tumors
were; lung cancer, hepatoma, and meningioma.
During the sameperiod there were three cancerrelated deaths in the unexposed population, the
tumor types being: colon carcinoma, hepatoma,
and myelodysplastic syndrome.
UTIRIK
|
Additional tumor diagnoses resulted from
clinical investigation initiated at the time of
medical team visits. These included a case of
breast carcinoma (detected by mammography)
and a case of colon carcinoma, both diagnosed
in exposed Utirik women. Both lesions were surgically resected and have a high probability of
being cured. In addition, an epithelioma was
removed from the skin of an exposed Rongelap
woman, the site of the lesion being in the
approximate area of a beta burn that developed
soonafter the 1954 exposure. This typeof lesion,
also termed basal cell carcinoma, is very common in the United States and is not included in
the detailed cancer statistics published by the
American Cancer Society (Silverberg and Lubera, 1987). However, its frequency in Marshallese is unknown.
_
|
J
PAPILLARY CANCER
? FOLLICULAR CANCER
|
“T
CUMULATIVE CASES WITH THYROID NODULES
°
a
on
(59%)
112%)
10-18 YR
Soe
0
\
(25%) |
l
Do
>18 YR
|
3
\
(149%)
~
\
9
Q
l
19
20
30.00
10°
(10%)
4
L
20
The development of two cases of hepatoma
among the population served by the medical
30
YEARS AFTER 1954
team requires comment. Two persons, one each
from the Utirik and the Comparison groups,
died from this tumor during the period covered
by this report, To this number should be added
the death of another Utirik man who died in
1984 from complications of cirrhosis {Adamset
al, 1985), for he, like one of the hepatoma
patients, had hepatitis B surface antigen
detected in his serum. Studies have demonstrated an association between hepatitis B surface antigenemia and hepatoma,cirrhosis, and
chronic active hepatitis (Beasley et al., 1981).
Early BNL observations revealed that infection
with hepatitis B virusis nearly universal among
Marshallese, as it is among manytropical populations, and that serological evidence of the
infection is commonin childhood. In view of the
Fig. 3: The accrual of cases with thyroid nodules and
thyroid cancer in the exposed Rongelap population
as a function of age at the time of exposurein 1954.
The <10 year group includes exposure in utero. Two
cases of thyroid atrophy without nodule formation (2
Rongeiap boys, <10 years of age) are excluded.(Figure taken from Robbins and Adams, 1989).
It appears that there is an inverse correlation
between the radiation dose absorbed by the thyroid and the time after exposure for development of the benign adenomatous nodules(Fig.
4). However, since the thyroid-absorbed radiation dose was determined primarily by age at
exposure (children receiving greater doses than
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ig
ar
t
1
tony
CF
ll