Cost-effectiveness of CT and PET-CT for determining the need for adjuvant neck dissection in locally advanced head and neck cancer

Background: Patients with node-positive head and neck squamous cell carcinomas (HNC) have a significant risk of residual disease (RD) in the neck after treatment, despite optimal chemoradiotherapy (CRT). Adjuvant neck dissection (ND) after CRT has been considered standard treatment, but its morbidity has led investigators to consider using postCRT imaging to determine the need for surgery. We analyzed the cost-effectiveness of computed tomography (CT) and positron emission tomography-computed tomography (PET-CT) as predictors of the need for ND compared with ND for all patients. Materials and methods: We developed a Markov model to describe health states in the 5 years after CRT for HNC in a 50-year-old man. We compared three strategies: dissect all patients, dissect patients with RD on CT, and dissect patients with RD on PET-CT. Probabilistic sensitivity analyses were carried out to model uncertainty in PET-CT performance, up-front and salvage dissection costs, and patient utilities. Results: ND only for patients with RD on PET-CT was the dominant strategy over a wide range of realistic and exaggerated assumptions. Probabilistic sensitivity analyses confirmed that the PET-CT strategy was almost certainly cost-effective at a societal willingness-to-pay threshold of $ 500 000/ quality-adjusted life year. Conclusion: Adjuvant ND reserved for patients with RD on PET-CT is the dominant and cost-effective strategy. original article