Utility of 99mTc-Sestamibi SPECT/CT in the Early Localization of Metastatic Parathyroid Carcinoma

Document Type : Case report

Authors

Department of Nuclear Medicine and PET Center St. Luke's Medical Center Bonifacio Global City, Taguig, Philippines

Abstract

Parathyroid carcinoma is very rare, with only a few documented cases. Hence, metastatic lesions are infrequently documented on scintigraphic imaging. We present a case of a 63-year-old female presenting with elevated serum levels of ionized calcium and parathyroid hormone (PTH) who was referred to our department for a parathyroid scan with SPECT/ CT. Parathyroid scintigraphy showed a focus of increased 99mTc-sestamibi uptake corresponding to a solid mass with calcification in the inferior pole of the right thyroid lobe; tracer retention was noted on delayed images. Incidentally, focal uptake was also seen in a soft tissue mass on the 7th right rib. The patient soon underwent total thyroidectomy, with biopsy revealing parathyroid carcinoma on the right lobe. A bone scan done 7 months after surgery confirmed the presence of metastatic bone disease. The concomitant detection of intrathyroidal and extrathyroidal sestamibiavid masses on parathyroid scintigraphy should increase clinical suspicion of a metastatic process from parathyroid carcinoma.

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  1. Elgazzar AH, Alenezi SA. Parathyroid gland. In: Elgazzar AH, editor. The pathophysiologic basis of nuclear medicine. 3rd ed. Switzerland: Springer International Publishing; 2015. P. 283-8.
  2. Ahmetbegović N, Suljagić N, Katica V. Significance of parathyroid scintigraphy and correlation of findings with parathyroid hormone values in patients undergoing hemodialysis. Med Glas (Zenica). 2017;14(2):158-63.
  3. Ziessman HA, O’Malley JP, Thrall JH. Endocrine System. The requisites: nuclear medicine. 4th ed. Philadelphia: Elsevier Health Sciences; 2014. P. 90-2.
  4. Wei CH, Harari A. Parathyroid carcinoma: update and guidelines for management. Curr Treat Options Oncol. 2012;13(1):11-23.
  5. Digonnet A, Carlier A, Willemse E, Quiriny M, Dekeyser C, de Saint Aubain N, et al.Parathyroid carcinoma: a review with three illustrative cases. J Cancer. 2011;2:532-7.
  6. Givi B, Shah JP. Parathyroid carcinoma. Clin Oncol (R Coll Radiol). 2010;22(6):498-507.
  7. Iacobone M, Lumachi F, Favia G. Up-to-date on parathyroid carcinoma: analysis of an experience of 19 cases. J Surg Oncol. 2004;88(4):223-8.
  8. Ruan M, Shen Y, Zhang H, Li M, Chen L. Bone metastasis from parathyroid carcinoma mon-avid for 99mTc-MIBI, 99mTc-MDP, and 18F-FDG. J Nucl Med Radiat Ther. 2014;5(1):165-8.
  9. Shane E. Clinical review 122: parathyroid carcinoma. J Clin Endocrinol Metab. 2001;86(2):485-93.

10. Choi JH, Kim KJ, Lee YJ, Kim SH, Kim SG, Jung KY, et al. Primary hyperparathyroidism with extensive brown tumors and multiple fractures in a 20-year-old woman. Endocrinol Metab. 2015;30(4):614-9.

11. Evangelista L, Sorgato N, Torresan F, Boschin IM, Pennelli G, Saladini G, et al. FDG-PET/CT and parathyroid carcinoma: review of literature and illustrative case series. World J Clin Oncol. 2011;2(10):348-54.