INTERESTING IMAGE
Primary Thyroid Osteosarcoma Staging and Evaluation of Response to Therapy With F-18 FDG PET-CT William Makis, MD, Javier-A. Novales-Diaz, MD, and Marc Hickeson, MD
Received for publication November 14, 2009; revision accepted December 8, 2009. From the Department of Nuclear Medicine, Royal Victoria Hospital, McGill University, Quebec, Canada. The manuscript has been read and approved by all the authors, and the requirements for authorship have been met. Each author believes that the manuscript represents honest work. Reprints: William Makis, Department of Nuclear Medicine, Royal Victoria Hospital, 687 Pine Ave West, Floor M2, Montreal, Quebec H3A 1A1, Canada. E-mail:
[email protected]. Copyright © 2010 by Lippincott Williams & Wilkins ISSN: 0363-9762/10/3507-0517
2. Trowell JE, Arkell DG. Osteosarcoma of the thyroid gland. J Pathol. 1976;119:123–127. 3. Syrjanen KJ. Fine needle aspiration cytology of the thyroid osteosarcoma: report of a case. J Cancer Res Clin Oncol. 1980;96:319 –323. 4. Tong GX, Hamele-Bena D, Liu JC, et al. Fine-needle aspiration biopsy of primary osteosarcoma of the thyroid: report of a case and review of the literature. Diagn Cytopathol. 2008;36:589 –594. 5. Nitzsche EU, Seeger LL, Klosa B, et al. Primary osteosarcoma of the thyroid gland. J Nucl Med. 1992;33:1399 –1401. 6. Yasuda S, Shohsu A, Ide M, et al. Diffuse F-18 FDG uptake in chronic thyroiditis. Clin Nucl Med. 1997;22:341. 7. Rohren EM. Intense FDG uptake in a benign Hurthle cell adenoma. Clin Nucl Med. 2004;29:664 – 666. 8. Choi JY, Lee KS, Kim HJ, et al. Focal thyroid lesions incidentally identified by integrated 18F-FDG PET/CT: clinical significance and improved characterization. J Nucl Med. 2006;47:609 – 615. 9. Are C, Hsu JF, Schoder H, et al. FDG-PET detected thyroid incidentalomas: need for further investigation? Ann Surg Oncol. 2007;14:239 –247. 10. Pryma DA, Schoder H, Gonen M, et al. Diagnostic accuracy and prognostic value of 18F-FDG PET in Hurthle cell thyroid cancer patients. J Nucl Med. 2006;47:1260 –1266. 11. Ong SC, Schoder H, Patel SG, et al. Diagnostic accuracy of 18F-FDG PET in restaging patients with medullary thyroid carcinoma and elevated calcitonin levels. J Nucl Med. 2007;48:501–507. 12. Bogsrud TV, Karantanis D, Nathan MA, et al. 18F-FDG PET in the management of patients with anaplastic thyroid carcinoma. Thyroid. 2008;18: 713–719. 13. Lee CJ, Hsu CH, Tai CJ, et al. FDG-PET for a thyroid MALT lymphoma. Acta Oncol. 2008;47:1165–1167. 14. Ozkan E, Tokmak E, Kir KM. Detection of thyroid plasmacytoma by F-18 FDG PET/CT imaging. Clin Nucl Med. 2008;33:292–293. 15. Jackson RT, Sinha P, Conrad GR. Demonstration of thyroidal metastasis from lung cancer by F-18 FDG PET scan. Clin Nucl Med. 2008;33:505–506.
Clinical Nuclear Medicine • Volume 35, Number 7, July 2010
www.nuclearmed.com | 517
Abstract: Extraosseous osteosarcomas account for less than 5% of all osteosarcomas. Primary osteosarcoma of the thyroid is a very rare tumor, with only 28 cases described in the published data. This is a case of a 40-year-old woman, 3 months postpartum, who presented with a rapidly growing mass in the neck, causing airway obstruction. An F-18 FDG PET-CT showed a large intensely FDG-avid mass in the thyroid gland, which was histopathologically confirmed to be a primary thyroid osteosarcoma. The patient was treated with tracheostomy, radiation therapy, and 2 cycles of chemotherapy. A posttherapy F-18 FDG PET-CT scan showed that the thyroid osteosarcoma was responding to therapy; however, the patient had developed new lung metastases. Key Words: thyroid osteosarcoma, extraosseous osteosarcoma, FDG, PET-CT, PET (Clin Nucl Med 2010;35: 517–520)
REFERENCES 1. Hertel V, Basten O, Bockmuhl U. Extraosseous osteosarcoma of the thyroid gland 关in German兴. Laryngorhinootologie. 2006;85:913–916.
Makis et al
Clinical Nuclear Medicine • Volume 35, Number 7, July 2010
FIGURE 1. A 40-year-old woman 3 months postpartum presented with a rapidly growing neck mass, causing airway obstruction. An emergency tracheostomy was performed and the patient was referred for an F-18 FDG PET-CT (Discovery ST, GE Healthcare, Canada). The maximum intensity projection images showed a large lobulated lesion involving both lobes of the thyroid and the isthmus, with maximal SUV of 14.6 on the right, 12.2 on the left, and 10.0 in the region of the isthmus. A total body iodine scan was not performed on this patient.
518 | www.nuclearmed.com
© 2010 Lippincott Williams & Wilkins
Clinical Nuclear Medicine • Volume 35, Number 7, July 2010
Primary Thyroid Osteosarcoma
FIGURE 2. A, Transaxial contrast-enhanced CT image shows an extensive mass involving the entire thyroid gland. B, PET; C, CT portion of the PET-CT; D, PET-CT fusion images. The thyroid mass extends retrosternally and encases the trachea with significant narrowing of the lumen. Histopathologic examination of the thyroid tissue obtained during tracheostomy showed islands of malignant bone and cartilage, abundant multinucleated giant cells (osteoclast type), and osteoid matrix material surrounding markedly pleomorphic spindle cells. There was extensive necrosis involving more than 50% of the tumor. The findings were consistent with primary thyroid osteosarcoma.1–3 Extraosseous osteosarcomas are rare, accounting for less than 5% of all osteosarcomas. Only 28 cases of primary thyroid osteosarcoma have been described in the published data.4 Approximately 1% of all thyroid tumors are reported to be sarcomas, including fibrosarcoma, hemangiosarcoma, osteosarcoma, and chondrosarcoma. The mean age of presentation of thyroid osteosarcoma is 62 years and female to male ratio is 1.5:1. Approximately 50% of patients have a long history of goiter. The prognosis is generally poor, with a vast majority of patients dying within 12 months of diagnosis.5 Increased F-18 FDG uptake in the thyroid gland is commonly seen in benign conditions such as chronic thyroiditis,6 Hurthle cell adenoma,7 follicular adenoma, and nodular hyperplasia,8 as well as a wide variety of malignancies including papillary and follicular, Hurthle cell, medullary, and anaplastic thyroid carcinomas,9 –12 lymphoma,13 plasmacytoma,14 and metastatic disease.15 This is a rare report of F-18 FDG PET-CT imaging of a primary thyroid osteosarcoma.
© 2010 Lippincott Williams & Wilkins
www.nuclearmed.com | 519
Makis et al
Clinical Nuclear Medicine • Volume 35, Number 7, July 2010
FIGURE 3. The patient was treated with radiation therapy and 2 cycles of cisplatin and doxorubicin chemotherapy. An F-18 FDG PET-CT done after the second cycle showed a significant reduction of FDG uptake in the thyroid mass, compatible with partial response to therapy, with maximal SUV 6.8. However, there were 2 new nodules in the right lung, the largest measuring 8 mm with SUV 2.5, which were suspicious for lung metastases. A chest CT done 3 months later demonstrated further growth of the nodules, compatible with metastatic disease.
FIGURE 4. Transaxial views of (A) CT, (B) PET, and (C) PET-CT show the new 8-mm metastasis in the right upper lung.
520 | www.nuclearmed.com
© 2010 Lippincott Williams & Wilkins
