A Rare Case of Papillary Thyroid Carcinoma Metastasizing to the Spine.

Papillary thyroid carcinoma (PTC) typically presents with an excellent prognosis. Distant metastasis, particularly to the spine, is rare and associated with poorer outcomes. This report highlights the importance of considering metastatic PTC in the differential diagnosis of persistent back pain in patients with thyroid abnormalities. A 61-year-old female presented with progressive lower back pain and an enlarging neck mass. Evaluation revealed a Thyroid Imaging Reporting and Data System, Category 4 (TIRADS-4) thyroid nodule and a lytic lesion in the T10 vertebra. Biopsy confirmed papillary thyroid carcinoma with metastasis to the spine. Spinal metastasis is an uncommon manifestation of PTC. This report underscores the need for vigilance regarding back pain in patients with a history of thyroid disease, as early detection can influence management and prevent complications. Spinal metastasis from PTC is rare but possible, even as a solitary lesion. Clinicians should consider PTC in the differential diagnosis of spinal lesions, particularly in patients with a history of thyroid abnormalities, to facilitate early diagnosis and treatment.