Abstract | OBJECTIVE: To investigate the usefulness of whole body scan (WBS) and serum thyroglobulin (Tg) measurement after thyroxine withdrawal during sequential follow-ups in patients with differentiated thyroid cancer (DTC). DESIGN: Two hundred and sixty-five consecutive DTC patients were enrolled. They were previously treated with near-total thyroidectomy and I-131 remnant ablation, without initial metastases or Tg antibodies. All had the first follow-up WBS and serum Tg measurement 6-12 months after initial treatment, and 165 patients received the second follow-up without further therapy. Positive/negative predictive values (PPV/NPV) were calculated by the outcome of patients being followed up for more than 8 years (mean+/-SD: 133+/-26 months). RESULTS: Serum Tg levels while the patients were off thyroxine therapy decreased spontaneously in 39.3% of the cases without further therapy. The NPV of the first follow-up serum Tg level was excellent: <2 microg/L and <0.5 microg/L were 95.1% and 98.2%, respectively. However, the PPV of the first follow-up serum Tg level was low: >10 microg/L and 2-10 microg/L were 40% and 9.6%, respectively. The trend of Tg levels was more informative; the PPV was 62.5% in cases with an increase of serum Tg of >10 microg/L and 16.6% with an increase of <5 microg/L. However, decreasing Tg levels may associate with rapid deterioration of disease, in which cases decrease of Tg indicated dedifferentiation of the tumor. The diagnostic WBS showed the same picture in 91.5% of the patients. Only one patient (0.6%) turned from negative study to positive during the follow-up. In the meanwhile his serum Tg levels increased from 0.56 to 13.6 microg/L. CONCLUSION: It is most informative when both the trend and the levels of Tg during sequential follow-up are considered. The diagnostic WBS may be performed for selected patients with indication based on Tg levels to localize the disease.
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Authors | Shu-Hua Huang, Pei-Wen Wang, Yu-Erh Huang, Fong-Fu Chou, Rue-Tsuan Liu, Shih-Chen Tung, Jung-Fu Chen, Ming-Chun Kuo, Jing-Rong Hsieh, Hsin-Hung Hsieh |
Journal | Thyroid : official journal of the American Thyroid Association
(Thyroid)
Vol. 16
Issue 12
Pg. 1273-8
(Dec 2006)
ISSN: 1050-7256 [Print] United States |
PMID | 17199438
(Publication Type: Journal Article)
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Chemical References |
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Topics |
- Adult
- Aged
- Carcinoma, Papillary
(diagnostic imaging, therapy)
- Female
- Follow-Up Studies
- Humans
- Male
- Middle Aged
- Neoplasm Metastasis
(diagnostic imaging)
- Predictive Value of Tests
- Radionuclide Imaging
- Substance Withdrawal Syndrome
- Thyroglobulin
(blood)
- Thyroid Neoplasms
(diagnostic imaging, therapy)
- Thyroxine
(therapeutic use)
- Whole Body Imaging
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