Clavicle metastasis from carcinoma thyroid- an atypical skeletal event and a management dilemma

Abstract

Bone metastases is a well described event in the natural history of thyroid cancers and has the potential to severely impact the quality of life by causing pain, fractures and spinal cord compression. Follicular thyroid carcinomas have a greater propensity for distal metastasis than papillary and anaplastic thyroid carcinomas. The most common sites of skeletal metastasis among thyroid cancer patients are femur followed by humerus, pelvis, radius, and scapula. Clavicle metastasis at initial presentation is exceedingly rare. Although many studies have examined the various prognostic factors for patients with bony metastases from thyroid cancers, very few have actually evaluated the effects of surgical management. We present an unusual case of metastatic papillary carcinoma thyroid presenting with clavicle metastasis and review the role of surgical management of bone metastases. Clavicular resection as a part of the management of metastatic papillary carcinoma thyroid has, to the best of our knowledge never been reported before.

Clavicular Metastasis as an Initial Presentation of Papillary Thyroid Cancer

“…While bone metastases are rare, they can manifest as a complication of aggressive thyroid carcinoma [ 3 ]. Bone has been reported as the second most common metastasis site with well-differentiated thyroid cancer, with follicular carcinoma more prevalent as an etiology (7–28%) than that of PTC origin (1.4–7%) [ 9 , 11 ]. To this end, our case depicts a unique presentation of thyroidal tissue metastases to the bone due to being confirmed a papillary subtype of well-differentiated thyroid cancer, which typically has a very low propensity for bone metastasis.…”

“…However, the clavicle's scarce red marrow and scant vascularity make it a rare location for malignancy [ 15 ]. As a result, metastatic involvement of the clavicle becomes an even more rare event (0–15% of all known clavicular lesions) with little known about its management [ 9 ]. Most presentations of clavicular lesions are reported in small case studies with a broad spectrum of presentations [ 16 ].…”

“…While the lung is considered the most common site of metastases from thyroid malignancy, bone metastases, if seen, are usually observed at skeletal sites such as the humerus, pelvis, radius, and scapula. PTC metastases to the clavicular bone as an initial presentation is a rare and unique finding [ 9 ]. We present a case of PTC that was first noticed as a growth on the right base of the neck and later found to have metastasized to the right clavicle.…”

Solitary metacarpophalangeal metastasis from poorly differentiated thyroid carcinoma: Excellent tumor marker and scan response to two fractions of radioiodine therapy

“…Apart from the rare site of metastasis from differentiated thyroid cancer, the case also illustrates the fact that small volume metastatic skeletal disease at times can demonstrate an excellent response to 131 I therapy. [ 1 2 3 4 5 ]…”