Long-Term Efficacy of Lymph Node Reoperation for Persistent Papillary Thyroid Cancer

Objective: The objective of the study was to determine the outcome of surgical resection of metastatic papillary thyroid cancer (PTC) in cervical lymph nodes after failure of initial surgery and I-131 therapy. Design: This was a retrospective clinical study. Setting: The study was conducted at a university-based tertiary cancer hospital. Patients: A cohort of 95 consecutive patients with recurrent/persistent PTC in the neck underwent initial reoperation during 1999-2005. All had previous thyroidectomy (+/- nodal dissection) and I131 therapy. Twenty-five patients with antithyroglobulin (Tg) antibodies were subsequently excluded. Main Outcome Measures: Biochemical complete remission (BCR) was stringently defined as undetectable TSH-stimulated serum Tg. Results: A total of 107 lymphadenectomies were undertaken in these 70 patients through January 2010. BCR was initially achieved in 12 patients (17%). Of the 58 patients with detectable postoperative Tg, 28 had a second reoperation and BCR was achieved in five (18%), seven had a third reoperation, and none achieved BCR. No patient achieving BCR had a subsequent recurrence after a mean follow-up of 60 months (range 4-116 months). In addition, two more patients achieved BCR during long-term follow-up without further intervention. In total, 19 patients (27%) achieved BCR and 32 patients (46%) achieved a TSH-stimulated Tg less than 2.0 ng/ml. Patients who did not achieve BCR had significant reduction in Tg after the first (P < 0.001) and second (P = 0.008) operations. No patient developed detectable distant metastases or died from PTC. Conclusions: Surgical resection of persistent PTC in cervical lymph nodes achieves BCR, when most stringently defined, in 27% of patients, sometimes requiring several surgeries. No biochemical or clinical recurrences occurred during follow-up. In patients who do not achieve BCR, Tg levels were significantly reduced. The long-term durability and impact of this intervention will require further investigation. (J Clin Endocrinol Metab 95: 2187-2194, 2010)