Lobectomy is a more Cost-Effective Option than Total Thyroidectomy for 1 to 4 cm Papillary Thyroid Carcinoma that do not Possess Clinically Recognizable High-Risk Features

Abstract

Background: Although lobectomy is a viable alternative to total thyroidectomy (TT) in low-risk 1 to 4 cm papillary thyroid carcinoma (PTC), lobectomy is associated with higher locoregional recurrence risk and need for completion TT upon discovery of a previously unrecognized histologic high-risk feature (HRF). The present study evaluated long-term cost-effectiveness between lobectomy and TT. Methods: Our base case was a hypothetical female cohort aged 40 years with a low-risk 2.5 cm PTC. A Markov decision tree model was constructed to compare cost-effectiveness between lobectomy and TT after 25 years. Patients with an unrecognized HRF (including aggressive histology, microscopic extrathyroidal extension, lymphovascular invasion, positive resection margin, nodal metastasis >5 mm, and multifocality) underwent completion TT after lobectomy. Outcome probabilities, utilities, and costs were estimated from the literature. The threshold for cost-effectiveness was set at US$50,000/quality-adjusted life-year (QALY). Sensitivity and threshold analyses were used to examine model uncertainty. Results: After 25 years, each patient who underwent lobectomy instead of TT cost an extra US$772.08 but gained an additional 0.300 QALY. The incremental cost-effectiveness ratio was US$2577.65/QALY. In the sensitivity analysis, the lobectomy arm began to become cost-effective only after 3 years. Despite varying the reported prevalence of clinically unrecognized HRFs, complication from surgical procedures, annualized recurrence rates, unit cost of surgical procedure or complication, and utility score, lobectomy remained more cost-effective than TT. Conclusions: Despite the higher locoregional recurrence risk and having almost half of the patients undergoing completion TT after lobectomy upon discovery of a previously unrecognized HRF, initial lobectomy was a more cost-effective long-term option than initial TT for 1 to 4 cm PTCs without clinically recognized HRFs.