Oncology 31: 153 156 (1975)
Cancer of the Thyroid following Radium Application to the Neck N. Walach, A . Hochman and E. Loewenthal Department of Oncology, Hadassah University Hospital, Jerusalem
Key Words. Thyroid carcinoma ■X-Ray treatment • Radium treatment Abstract. A young patient, suffering from thyroid carcinoma 24 years after radium treatment of the neck, is presented. The cancer appeared in the area which has been irradiated. In the present case, the thyroid was exposed to a relatively low dose of radiation. The importance of ionizing radiation and its carcinogenic effect in the juvenile thyroid are discussed.
Several reports have been published about induction of cancer of the thyroid by ionizing radiation, especially in childhood. They deal mainly with the effect of X-Ray on the region of the neck and neighbouring or adjoining parts (1 -4 , 6). In general, the patients were treated for benign conditions. Cancer induced by radium sources has been rarely reported. In fact, only three cases are known (5). In the following, a case of cancer of the thyroid gland is reported, which appeared 24 years after the application of radium. Case Report
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A female child. 1 year old, was treated in 1939/40 for an angiocavernoma in the anterior midline of the lower neck, overlying the isthmus and lower poles of the thyroid, 'flic visible part of the cavernoma was 3 X 1.5 cm in continuity with a slope infiltrating the skin around the raised area of the cavernoma, having a palpable margin of I cm. The treated area was 10 em! . The treatment was performed by a surface applicator of felt 1 cm thick in the first session and later continued with applicators of felt of 0.5 cm thickness. The treatment was started in October 1939 and was performed in five sessions (table I). The cavernoma had completely regressed by June 1942. During the treatment no erythema of the skin or any other reaction was noticed. In 1964, at the age of 26 years (24
WalachlHochman/l.oewenthal
154
Fig. 1. 1251 thyroid scan showing two cold nodules.
Table I. Dates of treatments and doses received by the patient Dose at 2 cm depth rad
Skin dose rad
October 18-19, 1939 January 11-12, 1940 March 27-28, 1940 July 18-19, 1940 December 10-11, 1940
1,096 420 420 816 442
520 204 204 368 199
293 116 116 192 102
Total dose (in 14 months)
3,194
1,495
819
years after radium treatment of the neck), when she was pregnant, the patient noticed a swelling in the lower part of the neck. It was more prominent on the left side measuring 2 X 1.5 cm and was 1.5 X 1.5 cm on the right side. The swelling was definitely localized to the thyroid, moving with the thyroid on deglutition. It was of rather soft consistency and not well limited. No lymph nodes were palpable. No retrosternal masses were evident. No signs of hyper- or hypothyroidism were present. X-Rays showed no evidence of pressure on the oesophagus or trachea. The BMR was in normal limits. l25I-uptake values were in the normal range. The scan showed two cold nodules (fig. 1).
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Dose at 1 cm depth rad
Date of treatment
Cancer of the Thyroid following Radium Application to the Neck
155
Considering the previous history of exposure to ionizing radiation, exploration of the neck was undertaken. At the operation, a malignant tumour was found. Total thyroid ectomy of the left side and subtotal thyroidectomy of the right side were performed. Histological diagnosis revealed: follicular adenocarcinoma. No metastatic nodes were found and no further treatment was considered at this stage. At present, the general condition of the patient is good. She attends regular check-ups and is maintained by thyroxine sodium (Synthroide) 0.1 mg/day.
X-Ray-induced carcinomas in the thyroid gland are a well-established fact. In the case reported, the cancer was induced by radium treatment. These cases of radium-induced carcinomas in the thyroid are rather rare. This case is re ported to stress the carcinogenicity of radiation and allows for observations which may lend to some generalizations. In cases of X-Ray-induced cancer of the thyroid, no precise data of the area exposed to radiation can be given, but the existing evidence would justify the assumption that the totality of the gland was exposed to the ionizing radiation. In the present case, the evidence shows that only the lower poles and isthmus of the gland were exposed to ionizing radiation. Because of the rapid fall-off of the radiation from the radium pack around the edges, the outline of the beam was the outline of the applicator, and the thyroid tissues affected were those parts of the thyroid under radium applicator. At the depth of 1 -2 cm (table I), the calculated thyroid dose was 1,495 rad at the depth of 1 cm and 819 rad at the depth of 2 cm. With respect to the skin, for which we have empirical information in humans, and experimental data in animals, the usual carcinogenic dose is in the range of 4,000-5,000 r. Quite often, the clinical situation may lead to exposure to X-Ray or supervoltage radiation in the range of 5,000 r or more. However, the reports of carcinoma of the thyroid in the adult exposed to high doses of radiation are rare. It is a common observation that the thyroid in treatment of cancer of the larynx or other malignant conditions of the neck can be exposed to high doses of radiation, without running the danger of inducing cancer in the gland. In the present case, the thyroid was exposed to a relatively low dose, be tween 1,495 and 819 rad. Yet a cancer was induced after a latent period of approximately 20 years. We may conclude that the thyroid in young people, in contrast to adults, is extremely sensitive to the carcinogenic effect of radiation. A further noticeable feature was the appearance of the cancer in the thyroid tissue underlying the applicator, while the rest of the gland was not affected. We may therefore conclude that the carcinogenic effect is a direct effect on the cell of the young thyroid.
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Discussion
Walach/Hochman/I.oewentltal
156
References
2 3 4 5
6
DeGroot, L. and Paloyan, E.: Thyroid carcinoma and radiation. J. Am. mod. Ass. 225: 487 491 (1973). Simpson, C.L.; Hempelmann, and Fuller, L.M.. Neoplasia in children treated with X-rays in infancy for thymic enlargement. Radiology 64: 840 845 (1955). Simpson, C.L. and Hempelmann, L.M.: The association of tumors and roentgen ray treatment of the thorax in infancy. Cancer, N.Y. 10: 42 56 (1957). Snegireff, L.S.: The elusiveness of neoplasia following roentgen therapy for thymic enlargement in childhood. Radiology 72: 508 517 (1959). Wilson, G.M.: Kilpatrick, R.: Eckert, //.: Curran, R.C.: Jepson, R.P.: Btomfield, G.W., and Miller, //.. Thyroid neoplasms following irradiation. Br. med. J. ii: 929 934 (1958). Wilson, S.M.; Plan, C., and Block, G.M.: Thyroid carcinoma after irradiation. Archs Surg., Chicago 100: 330 337 (1970).
N. Walach, MD, Department of Oncology, Hadassah University Hospital, Jerusalem (Israel)
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1
Cancer of the Thyroid following Radium Application to the Neck N. Walach, A . Hochman and E. Loewenthal Department of Oncology, Hadassah University Hospital, Jerusalem
Key Words. Thyroid carcinoma ■X-Ray treatment • Radium treatment Abstract. A young patient, suffering from thyroid carcinoma 24 years after radium treatment of the neck, is presented. The cancer appeared in the area which has been irradiated. In the present case, the thyroid was exposed to a relatively low dose of radiation. The importance of ionizing radiation and its carcinogenic effect in the juvenile thyroid are discussed.
Several reports have been published about induction of cancer of the thyroid by ionizing radiation, especially in childhood. They deal mainly with the effect of X-Ray on the region of the neck and neighbouring or adjoining parts (1 -4 , 6). In general, the patients were treated for benign conditions. Cancer induced by radium sources has been rarely reported. In fact, only three cases are known (5). In the following, a case of cancer of the thyroid gland is reported, which appeared 24 years after the application of radium. Case Report
Downloaded by: King's College London 137.73.144.138 - 1/21/2019 12:32:06 AM
A female child. 1 year old, was treated in 1939/40 for an angiocavernoma in the anterior midline of the lower neck, overlying the isthmus and lower poles of the thyroid, 'flic visible part of the cavernoma was 3 X 1.5 cm in continuity with a slope infiltrating the skin around the raised area of the cavernoma, having a palpable margin of I cm. The treated area was 10 em! . The treatment was performed by a surface applicator of felt 1 cm thick in the first session and later continued with applicators of felt of 0.5 cm thickness. The treatment was started in October 1939 and was performed in five sessions (table I). The cavernoma had completely regressed by June 1942. During the treatment no erythema of the skin or any other reaction was noticed. In 1964, at the age of 26 years (24
WalachlHochman/l.oewenthal
154
Fig. 1. 1251 thyroid scan showing two cold nodules.
Table I. Dates of treatments and doses received by the patient Dose at 2 cm depth rad
Skin dose rad
October 18-19, 1939 January 11-12, 1940 March 27-28, 1940 July 18-19, 1940 December 10-11, 1940
1,096 420 420 816 442
520 204 204 368 199
293 116 116 192 102
Total dose (in 14 months)
3,194
1,495
819
years after radium treatment of the neck), when she was pregnant, the patient noticed a swelling in the lower part of the neck. It was more prominent on the left side measuring 2 X 1.5 cm and was 1.5 X 1.5 cm on the right side. The swelling was definitely localized to the thyroid, moving with the thyroid on deglutition. It was of rather soft consistency and not well limited. No lymph nodes were palpable. No retrosternal masses were evident. No signs of hyper- or hypothyroidism were present. X-Rays showed no evidence of pressure on the oesophagus or trachea. The BMR was in normal limits. l25I-uptake values were in the normal range. The scan showed two cold nodules (fig. 1).
Downloaded by: King's College London 137.73.144.138 - 1/21/2019 12:32:06 AM
Dose at 1 cm depth rad
Date of treatment
Cancer of the Thyroid following Radium Application to the Neck
155
Considering the previous history of exposure to ionizing radiation, exploration of the neck was undertaken. At the operation, a malignant tumour was found. Total thyroid ectomy of the left side and subtotal thyroidectomy of the right side were performed. Histological diagnosis revealed: follicular adenocarcinoma. No metastatic nodes were found and no further treatment was considered at this stage. At present, the general condition of the patient is good. She attends regular check-ups and is maintained by thyroxine sodium (Synthroide) 0.1 mg/day.
X-Ray-induced carcinomas in the thyroid gland are a well-established fact. In the case reported, the cancer was induced by radium treatment. These cases of radium-induced carcinomas in the thyroid are rather rare. This case is re ported to stress the carcinogenicity of radiation and allows for observations which may lend to some generalizations. In cases of X-Ray-induced cancer of the thyroid, no precise data of the area exposed to radiation can be given, but the existing evidence would justify the assumption that the totality of the gland was exposed to the ionizing radiation. In the present case, the evidence shows that only the lower poles and isthmus of the gland were exposed to ionizing radiation. Because of the rapid fall-off of the radiation from the radium pack around the edges, the outline of the beam was the outline of the applicator, and the thyroid tissues affected were those parts of the thyroid under radium applicator. At the depth of 1 -2 cm (table I), the calculated thyroid dose was 1,495 rad at the depth of 1 cm and 819 rad at the depth of 2 cm. With respect to the skin, for which we have empirical information in humans, and experimental data in animals, the usual carcinogenic dose is in the range of 4,000-5,000 r. Quite often, the clinical situation may lead to exposure to X-Ray or supervoltage radiation in the range of 5,000 r or more. However, the reports of carcinoma of the thyroid in the adult exposed to high doses of radiation are rare. It is a common observation that the thyroid in treatment of cancer of the larynx or other malignant conditions of the neck can be exposed to high doses of radiation, without running the danger of inducing cancer in the gland. In the present case, the thyroid was exposed to a relatively low dose, be tween 1,495 and 819 rad. Yet a cancer was induced after a latent period of approximately 20 years. We may conclude that the thyroid in young people, in contrast to adults, is extremely sensitive to the carcinogenic effect of radiation. A further noticeable feature was the appearance of the cancer in the thyroid tissue underlying the applicator, while the rest of the gland was not affected. We may therefore conclude that the carcinogenic effect is a direct effect on the cell of the young thyroid.
Downloaded by: King's College London 137.73.144.138 - 1/21/2019 12:32:06 AM
Discussion
Walach/Hochman/I.oewentltal
156
References
2 3 4 5
6
DeGroot, L. and Paloyan, E.: Thyroid carcinoma and radiation. J. Am. mod. Ass. 225: 487 491 (1973). Simpson, C.L.; Hempelmann, and Fuller, L.M.. Neoplasia in children treated with X-rays in infancy for thymic enlargement. Radiology 64: 840 845 (1955). Simpson, C.L. and Hempelmann, L.M.: The association of tumors and roentgen ray treatment of the thorax in infancy. Cancer, N.Y. 10: 42 56 (1957). Snegireff, L.S.: The elusiveness of neoplasia following roentgen therapy for thymic enlargement in childhood. Radiology 72: 508 517 (1959). Wilson, G.M.: Kilpatrick, R.: Eckert, //.: Curran, R.C.: Jepson, R.P.: Btomfield, G.W., and Miller, //.. Thyroid neoplasms following irradiation. Br. med. J. ii: 929 934 (1958). Wilson, S.M.; Plan, C., and Block, G.M.: Thyroid carcinoma after irradiation. Archs Surg., Chicago 100: 330 337 (1970).
N. Walach, MD, Department of Oncology, Hadassah University Hospital, Jerusalem (Israel)
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1
