SUN-617 Metastatic Papillary Thyroid Cancer Presenting with Vertebral Fracture

Abstract: Of the major differentiated Thyroid malignancies, Papillary carcinoma has the highest incidence, representing 80% of cases and is most commonly diagnosed between the 3rd and 6th decade of life. Most commonly discovered as an asymptomatic thyroid nodule, Papillary carcinoma, due to its unencapsulated nature, preferentially invades local lymph nodes over hematogenous spread. Distant metastases are rare of Papillary carcinoma and even more unusual as the presenting symptom.Here we present the case of a 73 year old Caucasian Female who presented to the ED with 3 months of constant progressively worsening lower back pain. She reports associated pain into her right lateral thigh and tingling sensations over the left lateral thigh. Patient denied bladder/bowel dysfunction or saddle anesthesia. To manage the pain, our patient had been taking a full dose aspirin and was seeing a chiropractor who had given her the diagnosis of herniated disks from xray radiography. Increased severity of her pain had brought her into the ED. On physical exam, our patient had point tenderness over her lumbar spine, without any motor sensory defects. ED CT scan demonstrated a comminuted compression fracture of her L3 spine with bilateral neural forminal compromise. MRI the following day confirmed the findings. Intraoperatively during correction of the compression fracture, biopsy of the bone was sent to for analysis. The sample stained positive for TTF, thyroglobulin and PAX-8 all consistent with metastatic thyroid cancer. In the following days, our patient had an Ultrasound that confirmed a 1.6cm nodule in the right thyroid lobe. Fine needle Aspiration confirmed the findings on biopsy. Definite treatment involved thyroidectomy and samples under microscopy showed papillary cell carcinoma of the thyroid gland. Discussion: Due to its slow course and minimal invasiveness, Papillary thyroid carcinoma has great outcomes after medical and surgical management. In 90% of cases, this cancer presents as a thyroid nodule and rarely metastasizes. Ultrasound and FNA can lead to a timely diagnosis and elective surgical management can be scheduled. The standard of care is complete thyroidectomy and follow up radioactive Iodine therapy are used as definitive treatment for this malignancy, resulting in a 80% ten year survival rate. Success of management drops significantly if there is metastasis of Papillary thyroid carcinoma with some studies suggesting a 10 year survival rate at 40% and only 21% if there is bone metastasis. After the lungs and liver, bone is the 3rd most common site papillary thyroid carcinoma metastasis to. Conclusion: This presentation of spinal metastasis and the resulting compression fracture as presenting symptoms of papillary Thyroid cancer is a rare presentation of this malignancy.