z-logo
Premium
Is calculation of the dose in radioiodine therapy of hyperthyroidism worth while?
Author(s) -
Jarløv Anne E.,
Hegedüst Laszio,
Kristensen Lars Ø.,
Nygaard Birte,
Hansen Jens M.
Publication year - 1995
Publication title -
clinical endocrinology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.055
H-Index - 147
eISSN - 1365-2265
pISSN - 0300-0664
DOI - 10.1111/j.1365-2265.1995.tb02039.x
Subject(s) - endocrinology , medicine , radioiodine therapy , thyroid , thyroid cancer
Summary OBJECTIVE The persistent controversy as to the best approach to radioiodine dose selection in the treatment of hyperthyroldism led us to perform a study in order to compare a fixed dose regime comprising doses of 185, 370 or 555 MBq based on gland size assessment by palpation only, with a calculated 131 I dose based on type of thyroid gland (diffuse, multinodular, solitary adenoma), an accurate thyroid volume measurement, and a 24‐hour 131 I uptake determination. DESIGN Prospective randomized study. PATIENTS Two hundred and twenty‐one consecutive hyperthyroid patients referred for 131 I treatment. Four patlents who dled for reasons unrelated to hyperthyroidism, 7 lost to follow‐up and 47 who did not receive antithyroid drugs after treatment, were excluded. The remalnlng 163 patlents (143 women) were studied, dlvlded into subgroups accordlng to the type of gland. They all recelved antithyroid drugs prior to 131 I treatment and this was resumed 7 days after treatment for a period of 3 weeks. MEASUREMENTS Thyroid function variables were determined approximately 2 weeks before 131 I treatment, and again 1, 2, 3, 6, 9 and 12 months after treatment. Prior to 131 I therapy the size of the thyroid gland was determined by ultrasound and a 24‐hour uptake of 131 I was carried out. Thyroid in 78 of the 163 patients. Twelve months after the initial 131 I dose patients could be classified as euthyroid, hyperthyrold or hypothyroid. RESULT Neither in the group of 163 patients nor within the three subgroups of hyperthyroidism could any significant difference in outcome between the two treatment regimes be demonstrated. Thirty‐two of 78 patients (41%) in the calculated dose group and 30 of 85 patients (35%, NS) in the fixed group were classified as hyperthroid. Seven of 78(9%) in the calculated dose group were classified as permanently hypothyroid. Finally, 39 of 78(50%) In the calculated dose group and 49 of 85(58%, NS) in the fixed group were enthyroid at 12 months after 131 I treatment. One year after 131 I therapy thyroid volume was deduced from 59.3 ± 9.2 (mean ± SEM) to 36.2 ± 6.6 ml (average reduction 39%) In the calculated dose group (P < 0.001). This reduction did not differ significantly from the fixed dose group where thyroid volume declined from 61.6 ± 6.1 to 41.17 ± 4.7 ml (average reduction 32%) (P < 0.001). CONCLUSIONS A semiquantitative approach is probably as good as the more elaborately calculated radiolodine dose for treatment of hyperthyroidism. It is clearly more cost effective and allows the use of predetermined standard doses.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here