What's in a Name? A Cost-Effectiveness Analysis of the Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features (NIFTP) Nomenclature Revision.

BACKGROUND The noninvasive subtype of encapsulated follicular variant of papillary thyroid carcinoma (eFVPTC) has recently been reclassified as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) to reflect the indolent behavior and favorable prognosis of the tumor. This terminology change has also de-escalated its management approach from cancer treatment to a more conservative treatment strategy befitting a benign thyroid neoplasm. OBJECTIVE To characterize the reduced healthcare costs and improved quality-of-life from management of NIFTP as a nonmalignant tumor vs. previous management as eFVPTC Methods: A cost-effectiveness analysis was performed by creating Markov models to simulate two management strategies for NIFTP: 1) de-escalated management of the tumor as NIFTP involving lobectomy with reduced follow-up, 2) management of the tumor as eFVPTC involving completion thyroidectomy/radioactive iodine ablation for some patients and follow-up recommended for carcinoma. The model was simulated for 5 and 20 years following diagnosis of NIFTP. Aggregate costs and quality-life years were measured. One-way sensitivity analysis was performed for all variables. RESULTS Over a 5-year simulation period, de-escalated management of NIFTP had a total cost of $12,380.99 per patient while the more aggressive management of the tumor as eFVPTC had a total cost of $16,264.03 per patient (saving $3,883.05 over 5 years). Management of NIFTP provided 5.00 quality adjusted life years, while management as eFVPTC provided 4.97 quality adjusted life years. Sensitivity analyses showed that management of NIFTP always resulted in lower costs and greater quality-adjusted life years (QALYs) over the sensitivity ranges for individual variables. De-escalated management for NIFTP is expected to produce approximately $6-42 million in cost savings over a 5-year period for these patients and incremental 54 - 370 QALYs of increased utility in the United States. CONCLUSION The degree of cost savings and improved patient utility of de-escalated NIFTP management compared to traditional management was estimated to be $3,883.05 and 0.03 QALYs per patient. We demonstrated that these findings persisted in sensitivity analysis to account for variability in recurrence rate, surveillance approaches, and other model inputs. These findings allow for greater understanding of the economic and quality-of-life impact of NIFTP re-classification.