Does Long-term Surveillance Imaging Improve Survival in Patients Treated for Head and Neck Squamous Cell Carcinoma? A Systematic Review of the Current Evidence.

Abstract

Long-term post-treatment surveillance imaging algorithms for head and neck squamous cell carcinoma are not standardized due to debates over optimal surveillance strategy and efficacy. Consequently, current guidelines do not provide long-term surveillance imaging recommendations beyond 6 months. We performed a systematic review to evaluate the impact of long-term imaging surveillance (i.e., imaging beyond 6 months following treatment completion) on survival in patients treated definitively for head and neck squamous cell carcinoma. A search was conducted on PubMed, Embase, Scopus, the Cochrane Central Register of Controlled Trials, and Web of Science for English literature published between 2003 and 2024 evaluating the impact of long-term surveillance imaging on survival in patients with head and neck squamous cell carcinoma. 718 abstracts were screened and 95 underwent full-text review, with 2 articles meeting inclusion criteria. The Risk of Bias in Non-randomized Studies of Interventions assessment tool was used. A qualitative assessment without a pooled analysis was performed for the two studies meeting inclusion criteria. No randomized prospective controlled trials were identified. Two retrospective two-arm studies were included comparing long-term surveillance imaging with clinical surveillance and were each rated as having moderate risk of bias. Each study included heterogeneous populations with variable risk profiles and imaging surveillance protocols. Both studies investigated the impact of long-term surveillance imaging on overall survival and came to a different conclusion with one study reporting a survival benefit for long-term surveillance imaging with FDG PET/CT in patients with stage III or IV disease or an oropharyngeal primary tumor and the other study demonstrating no survival benefit. Limited heterogeneous retrospective data available precludes definitive conclusions on the impact of long-term surveillance imaging in head and neck squamous cell carcinoma. There is insufficient quality evidence regarding the impact of long-term surveillance imaging on survival in patients treated definitively for head and neck squamous cell carcinoma. There is a lack of standardized definition of long-term surveillance, variable surveillance protocols, and inconsistencies in results reporting, underscoring the need for a prospective multi-center registry assessing outcomes. HNSCC = Head and Neck Squamous Cell Carcinoma; RT= radiotherapy; NCCN = National Comprehensive Cancer Network; MPC = metachronous primary cancer; CR = complete response; OS = overall survival; CRT = chemoradiotherapy; HPV = human papillomavirus; PFS = progression-free survival; CFU = clinical follow up; NI-RADS = Neck Imaging Reporting and Data System.