Korean J Endocr Surg.  2010 Dec;10(4):249-255. 10.16956/kjes.2010.10.4.249.

Incidental Findings of Thyroid Detected by PET-CT during Cancer Follow-up

• Kim JS
• Choi SY
• No HK
• Kim SJ
• Kim YJ
• Hyun IY
• Kim YM
• Cho YU

• KMID: 2375478
• DOI: http://doi.org/10.16956/kjes.2010.10.4.249

Abstract

PURPOSE
The incidence of thyroid cancer is increasing in Korea, partially owing to the development of diagnostic tools. Positron emission tomography (PET)-computed tomography (CT), in particular, has generally been used for evaluation of metastasis and follow-up of malignancy.
METHODS
We retrospectively investigated 2,833 patients with PET-CT for metastasis work-up or cancer follow-up, which was performed between January 1998 and May 2008 at Inha University Hospital. Of them, abnormal thyroid findings were discovered in 181 patients and we studied the result of further evaluation or follow-up PET-CT.
RESULTS
Thyroid cancer was diagnosed in 26 patients, including metastatic cancer in 3 patients, and non-operated primary cancer in 2 patients. Other 21 patients received operation, which in all histopathologically revealed papillary carcinoma. The mean age of the 21 patients was 55.4 years. Nine patients had a history of radiotherapy. The site of malignant nodule was discordant between PET-CT and histopathologic result in 6 patients. The mean size of malignant nodules was 9.45 mm (0.1~23 mm) with microcarcinoma in 10 patients (47.6%). The mean interval between diagnoses was 15.8 months, and in 4 patients operations for two malignancies were performed in a same day. The incidence of thyroid cancer was significantly high in female patients, but the differences of incidence among different cancer groups were not significant for female patients.
CONCLUSION
Early diagnosis of synchronous or secondary thyroid cancer by PET-CT in cancer patients can make early treatment and better strategies for multiple malignancies possible.

Keyword

Thyroid cancer; Positron emission tomography; Incidental findings

MeSH Terms

Carcinoma, Papillary
Diagnosis
Early Diagnosis
Female
Follow-Up Studies*
Humans
Incidence
Incidental Findings*
Korea
Neoplasm Metastasis
Positron-Emission Tomography
Radiotherapy
Retrospective Studies
Thyroid Gland*
Thyroid Neoplasms

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