Sternal metastasis as first manifestation of a papillary thyroid carcinoma: A case report

Abstract

Introduction: Papillary thyroid carcinomas (PTC) are differentiated forms of thyroid carcinoma. Sternal metastases from differentiated thyroid cancers (DTCs) are rare and are of particular prognostic interest. Radioiodine therapy has traditionally been the treatment of choice for metastases from differentiated thyroid cancers; however, bone metastases are known to be resistant to this form of treatment. Surgical resection of distant metastases from DTCs offers a better chance of achieving long survival and a better quality of life. We report the case of a 59-year-old women who presented a presternal mass for one year revealing metastatic papillary thyroid carcinoma, a total thyroidectomy with lymph node dissection and reconstruction of the sternal defect were performed. Overall, we demonstrate that radical resection of sternal metastases can be performed safely even in patients with poor prognosis to achieve palliation and potentiation of Radioiodine therapy.

Case report: This is a 59-year-old women referred by the endocrinology service for a sternal metastasis of a papillary thyroid carcinoma, who presented a painless, firm and fixed presternal mass for one year, a total thyroidectomy with lymph node dissection was performed with En-bloc resection and reconstruction as a one-stage procedure. Reconstruction of the chest wall was obtained by the rigid reconstruction with titanium bars and coverage with polymesh dual prosthesis, followed by radioiodine therapy and substitution with L-thyroxine. The patient is currently in good health condition, and does not present any complications and was in euthyroidism under substitution for the long term follow up.

Discussion: Thyroid cancer is the fastest increasing cancer in the United States, It is expected to replace colon cancer as the fourth leading cancer by 2030.2 More than 90% of thyroid carcinoma cases are classified as papillary or follicular carcinoma, both referred to as differentiated thyroid carcinomas (DTCs) and are associated with a 97%-98% 10-year survival rate. However, this rate can decrease to 14%-21% when patients present with bone metastases. Bone metastases have been reported to occur in 2%-13% of patients with DTC (Osorio et al. [1]). Several techniques have been used to repair after wide sternal resection for metastatic malignancies. Furthermore, choice of the reconstruction techniques depends on the size and the site of the defect and the preference of the surgeon (Lequaglie et al. [2]).

Conclusion: Sternal metastases from papillary thyroid carcinomas are rare,few cases of sternal metastasis as first presentation of a well-differentiated PTC are described in the literature. Operative management of these metastases is still controversial, but radical resection offer patients an optimal probability of long-term survival.

Keywords: Papillary thyroid carcinoma (PTC); Secondary sternal neoplasms; Surgical resection.

Fig. 1

Contrast-enhanced CT, marked with arrows: (A) the sternal destruction and expansion by the metastases, (B) the retro sternal extension of the thyroid tumour, (C),(D): axial and sagittal planes CT showing the sternal metastasis and the thyroid tumour.

Fig. 2

Perioprative images marcked with arrow (A) thyroid carcinoma and sternal mass, (B) 1 st surgical step: total thyroidectomy, (C) specimen, (D) 2nd surgical step :Sternal resection and reconstruction using Titanium bars and coverage with Polydual Mesh.

Fig. 3

Histhopathology (A) bone localization of papillary thyroid carcinoma,(B) diffuse expression of thyroglobulin.