Thoracic metastasectomy for thyroid malignancies

Objective: To better define early and long-term outcomes of patients undergoing thoracic metastasectomy for thyroid cancer. Methods: We identified, reviewed, and analyzed the medical records of all patients who underwent thoracic metastasectomy for thyroid cancer in our institution from 1971 to 2006. Results: There were 48 patients (25 men, 23 women). A complete resection (R0) of all known disease was performed in 33 (69%) patients, while 15 (31%) underwent incomplete resection (R1 or R2). By histology, the majority were papillary 31 (65%), follicular 8 (17%), medullary 5 (10%), and Hürthle cell 4 (8%). Ninety percent were confined to a single side of the chest, with 10% presenting with bilateral metastases. Thoracotomy was performed in 28 (58%), sternotomy in 12 (25%), and thoracoscopy was used in 8 (17%). Operative mortality was zero and postoperative complications occurred in 8 patients (17%). There are currently 18 surviving patients from the cohort (37%) with a median follow-up of 10 years (range, 1 month to 17 years). The overall 5-year survival after thoracic metastasectomy was 60%. Based on histology, 5-year survival for papillary cancer was 64% compared to 37% for follicular and Hürthle cell neoplasms (p = 0.03). All five medullary thyroid cancer patients were alive at 5 years. Five-year survival was also improved for patients less than 45 years old at the time of diagnosis of their initial thyroid malignancy (94% vs 49%; p = 0.03). Disease-free interval of >3 years between initial thyroid malignancy diagnosis and thoracic metastasectomy demonstrated improved 5-year survival (67% vs 52%; p = 0.01). Conclusion: Pulmonary resection for thyroid metastasis is safe with low morbidity and mortality. Retrospective analysis demonstrates improved long-term survival in patients with papillary histology, longer disease-free interval (>3 years) and younger age at diagnosis of initial thyroid malignancy. Excellent long-term survival was also achievable in selected patients with medullary thyroid metastasis.