Safety and cost analysis of an 18FDG-PET-CT response based follow-up strategy for head and neck cancers treated with primary radiation or chemoradiation

Summary Background Prognostic information can rationalise clinical follow-up after radical cancer treatment. This retrospective cohort study of radical head and neck (chemo)radiotherapy patients examines the clinical safety and cost implications of stratifying follow-up intensity by post-treatment 18 FDG-PET-CT response. Methods In 2008 clinical review after radical head and neck radiotherapy was reduced from 3- to 6-monthly for patients with complete 18 FDG-PET-CT response at 3 months. 184 patients treated after this change (“PET Stratified”, 2009–11) were compared to 178 patients treated before (“Standard”, 2005–7). Clinical safety was assessed by the time to detection of recurrence, overall survival and potential for radical treatment of recurrence. A hospital cost analysis was performed using individual patient data. Results 127 of 178 Standard and 148 of 184 PET Stratified patients achieved complete response on post-treatment imaging. Baseline clinical characteristics were comparable. Median follow-up from response assessment was 4.8 years in the Standard cohort and 2.1 years for PET Stratified. PET Stratified patients had a mean 4.4 outpatient visits in 2 years, compared to 7.0 among Standard patients. Over 90% of patients remained free of recurrence at 2 years in both cohorts. Time to detection of recurrence was similar between two cohorts (HR1.05, 95%CI 0.45–2.52), as was overall survival (HR0.91, 95%CI 0.36–2.29). The proportion of radically treatable recurrences was also similar (42% Standard vs. 47% PET Stratified). The hospital cost savings per patient from reduced review were AUD$2606 over 2 years, AUD$5012 over five. Conclusion 18 FDG-PET-CT to stratify follow-up intensity after radical radiotherapy for head and neck cancer reduces costs with no apparent clinical detriment.