INTERESTING IMAGE Laryngeal Giant Cell Tumor Mimicking Thyroid Cancer Demonstrated by PET/CT Chih-Yung Chang, MD,* Li-Fan Lin, MD,* Yaoh-Shiang Lin, MD,† Yi-Jen Peng, MD,‡ Wen-Sheng Huang, MD,* and Shiou-Chi Cherng, MD* Abstract: A 53-year-old man was referred for combined F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/ computed tomography (CT) imaging to evaluate a protruding mass in the right anterior neck. PET/CT images showed a level III nodular lesion with intense FDG uptake in the above-mentioned region. Surgical excision was performed under the impression of thyroid cancer. Histopathologic evaluation, however, revealed a giant cell tumor of thyroid cartilage. Key Words: F-18 fluorodeoxyglucose, positron emission tomography/computed tomography, giant cell tumor, thyroid cartilage (Clin Nucl Med 2007;32: 390 –392) REFERENCES 1. Sakurai H, Mitsuhashi N, Hayakawa K, Niibe H. Giant cell tumor of the thoracic spine simulating mediastinal neoplasm. Am J Neuroradiol. 1999;20:1723. 2. Goldenberg RR, Campbell CJ, Bonfiglio M. Giant-cell tumor of bone. An analysis of two hundred and eighteen cases. J Bone Joint Surg Am. 1970;52:619. 3. Wang K, Allen L, Fung E, et al. Bone scintigraphy in common tumors with osteolytic components. Clin Nucl Med. 2005;30:655. 4. Biscaglia R, Bacchini P, Bertoni F. Giant cell tumor of the bones of the hand and foot. Cancer. 2000;88:2022. 5. Wieneke JA, Gannon FH, Heffner DK, et al. Giant cell tumor of the larynx: a clinicopathologic series of eight cases and a review of the literature. Mod Pathol. 2001;14:1209. 6. Martin PC, Hoda SA, Pigman HT, et al. Giant cell tumor of the larynx. Case report and review of the literature. Arch Pathol Lab Med. 1994; 118:834. 7. Haubrich J. Development of carcinoma on the surface of a vocal cord giant-cell tumor. Hno. 1966;14:176. 8. Moubayed AP, Wiebringhaus H. Three cases of giant cell fibroma of the vocal cord. Arch Otorhinolaryngol. 1977;217:193. 9. Strauss LG, Dimitrakopoulou-Strauss A, Koczan D, et al. 18 F-FDG kinetics and gene expression in giant cell tumors. J Nucl Med. 2004;45: 1528. 10. Aoki J, Watanabe H, Shinozaki T, et al. FDG PET of primary benign and malignant bone tumors: standardized uptake value in 52 lesions. Radi- ology. 2001;219:774. 11. Nair N, Agrawal A, Nayak UN. Detection of thyroid carcinoma in wall of a cystic lesion by FDG PET. Clin Nucl Med. 2005;30:647. 12. Hsu CH, Wu CH, Chu JS. Metastatic cancer in thyroid detected by FDG PET. Clin Nucl Med. 2006;31:51. 13. Leboeuf R, Benard F, Langlois MF. Thyroid cancer presenting as a PET incidentaloma in a patient with concomitant breast cancer metastases to the thyroid. Clin Nucl Med. 2006;31:382. 14. Roscoe KJ, Raja S, Tronic B, et al. Single F-18 fluorodeoxyglucose positron emission tomography hypermetabolic focus containing meta- static papillary thyroid cancer within a primary scarring adenocarcinoma lung cancer. Clin Nucl Med. 2006;31:359. Received for publication October 29, 2006; revision accepted January 24, 2007. From the Departments of *Nuclear Medicine, †Otorhinolaryngology-Head & Neck Surgery, and ‡Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China. Reprints: Dr. Shiou-Chi Cherng, Department of Nuclear Medicine, Tri- Service General Hospital, 325, Section 2, Cheng-Kung Road, Taipei 114, Taiwan, Republic of China. E-mail: scc9130@yahoo.com.tw. Copyright © 2007 by Lippincott Williams & Wilkins ISSN: 0363-9762/07/3205-0390 Clinical Nuclear Medicine • Volume 32, Number 5, May 2007 390