The Usefulness of Diagnostic Scan Using Technetium-99m Pertechnetate Scintigraphy prior to the First Ablative Radioiodine Treatment in Patients with Well Differentiated Thyroid Carcinoma: A Comparative Study with Iodine-131.
- Author:
Seok Nam YOON
;
Chan H PARK
;
Kyung Hoon HWANG
;
Su Zy KIM
;
Eui Young SOH
;
Kyung Rae KIM
- Publication Type:Comparative Study ; Original Article
- Keywords:
Tc-99m pertechnetate;
Iodine-131;
Ablative therapy;
Thyroid cancer
- MeSH:
Diagnostic Imaging;
Hand;
Humans;
Lymph Nodes;
Neoplasm Metastasis;
Prospective Studies;
Radionuclide Imaging*;
Sodium Pertechnetate Tc 99m*;
Thyroid Gland*;
Thyroid Neoplasms*;
Thyroidectomy
- From:Korean Journal of Nuclear Medicine
2000;34(4):285-293
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: A prospective comparison was made between imaging with Tc-99m pertechnetate (Tc-99m) and Ioine-131 (I-131) for the detection of residual and metastatic tissue after total thyroidectomy in patients with well-differentiated thyroid carcinoma. MATERALS AND METHODS: Initially our patients had imaging with Tc-99m, followed by I-131 within 3 days. The study included 21 patients who had ablation with high dose of I-131 ranging from 100 mCi to 150 mCi. Planar and pinhole images were acquired for both Tc-99m and I-131. Diagnostic images of Tc-99m and I-131 were compared with post-therapy images. Degree of uptake on Tc-99m and I-131 images was scored by four point scale and compared. RESULTS: The results of the Tc-99m study were: 16 of 19 studies (84%) were positive on simple planar images, but 19 of 20 studies (95%) were positive on pinhole images. Conventional I-131 diagnostic imaging on the other hand showed that all studies (100%) were positive on both planar and pinhole images. There was a significant difference in degree of uptake between Tc-99m and I-131 planar images (p<0.05). Only one case of Tc-99m scintigraphy was negative on both planar and pinhole studies (false negative). There was no distant metastasis on the therapeutic I-131 images. CONCLUSION: Tc-99m scan using pinhole in certain clinical situations is an alternative to the I-131 scan in detecting thyroid or lymph node metastasis prior to the first ablative treatment after thyroidectomy for well-differentiated thyroid carcinoma.
