Unusual Metastasis of Papillary Thyroid Cancer to the Thoracic Spine: A Case Report, New Surgical Management Proposal, and Review of the Literature.

Papillary thyroid carcinoma (PTC) is significantly more common than follicular thyroid carcinoma (FTC), yet FTC has a much higher tendency to metastasize to the spinal column. We present a rare case of a metastatic thoracic spinal column lesion originating from the PTC. Thyroid carcinoma is known to be highly vascular with a significant tendency to hemorrhage during surgical resection. This increased tendency to hemorrhage leads to unanticipated intraoperative risks when the type of cancer is not diagnosed before surgical resection. Complications related to intraoperative bleeding can be prevented by visualization using angiography and preoperative embolization. The type of cancer is ideally diagnosed before tumor resection either by the standard metastatic workup or histologically after the biopsy. However, limitations exist in these methods, therefore, hypervascular tumors such as metastatic thyroid cancer can go undiagnosed until after surgical resection. In addition to our case report, we present a review of the literature regarding diagnostic and treatment strategies for hypervascular thyroid tumors and propose a new algorithm for the surgical management of spinal tumors with an unknown origin for optimization of preoperative and perioperative care.