Thallium-291 Whole Body Scintigraphy in Postoperative Follow-up of Differentiated Thyroid Carcinoma.
- Author:
Eun Sook KIM
1
;
Hong Kyu KIM
;
Sung Jin LEE
;
Jin Sook RYU
;
Dae Hyuk MOON
;
Young Kee SHONG
Author Information
1. Department of Internal Medicine, University of Ulsan, College of Medicine, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
Differentiated thyroid carcinoma;
Thallium-201 scan;
131I scan;
Thyroglobulin
- MeSH:
Follow-Up Studies*;
Humans;
Lung;
Lymph Nodes;
Neoplasm Metastasis;
Radionuclide Imaging*;
Thallium;
Thyroglobulin;
Thyroid Gland*;
Thyroid Neoplasms*;
Thyroidectomy;
Thyrotropin;
Whole Body Imaging
- From:Journal of Korean Society of Endocrinology
1999;14(1):63-70
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: The advantages of thallium (Tl)-201 whole body scan in follow-up of patients with thyroid carcinoma include no need to discontinue thyroid hormone replacement, a shorter period of time between injection and imaging, a lower radiation dose, and preservation of affinity for subsequent therapeutic dose of 131I. To evaluate the reliability of whole body scintigraphy using Tl-201 in postoperative follow-up of thyroid carcinoma, this procedure was performed in patients after total thyroidectomy for thyroid carcinoma. The results were compared with those of 131I scintigraphy. METHODS: One hundred nineteen cases (119 patients) with a median age of 43 years (range, 20 85 years) were included in the study. After optimal endogenous thyroid-stimulating hormone stimulation (>50 mIU/mL), 131I (4 mCi) scan and Tl 201 (3 mCi) scan were simultaneously performed. Concomitantly serum thyroglobulin and anti-thyroglobulin antibody levels were checked. If abnormal findings on any of the scintigraphic methods or high levels of thyroglobulin (> 10 ng/mL) were detected, high dose (150~200mCi) 131I was administered as therapy and then whole body scans were performed repeatedly after the therapy. The presence or absence of thyroid cancer was established by pathologic, radiologic, and/or high dose 131I scan findings. RESULTS: In 12 patients, ll-201 scan revealed positive accumulations which were not found on 131I scan, of whom 9 had elevated thyroglobulin levels. In these cases, 5 cases were interpreted to have normal thyroid remnant and 7 cases showed pathologic findings (1 lung, 2 lymph node, 1 bone, and 2 lung and lymph node metastasis, and 1 false positive accumulation of thallium). Metastasis were confirmed histologically in 2 and radiologically in 5 cases. Negative Tl-201 scans, despite of positive 131I scans, occurred in 20 patients, of whom 6 had abnormal thyroglobulin levels. Seventeen cases were interpreted to have thyroid remnant, 2 cases were diagnosed to have thyroid carcinoma metastasis (1 lung, 1 lung and lymph node), and 1 case was not confumed. CONCLUSION: These results suggest that 131I scan is superior to 11-201 scan for detection of residual or metastatic differentiated thyroid carcinoma. However, the use of combined modalities may provide a higher diagnostic yield. TI-201 scan can be useful especially in cases in which 'I scan is negative despite of abnormal thyroglobulin levels.
