A systematic review and meta-analysis of the role of positron emission tomography in the follow up of head and neck squamous cell carcinoma following radiotherapy or chemoradiotherapy

Objectives: This review examines the effectiveness of positron emission tomography (PET) in the detection of recurrent or persistent head and neck squamous cell carcinoma after radiotherapy or chemoradiotherapy. Design: A systematic review and meta-analysis of trials of PET for detecting residual/recurrent head and neck squamous cell carcinoma treated by radiotherapy or chemoradiotherapy. Trials were quality assessed using the Quality Assessment of Diagnostic Accuracy Studies tool for assessing diagnostic accuracy studies. Quantitative data were extracted and a bivariate random effects model used to calculate pooled sensitivity and specificity. Setting: Tertiary referral head and neck centre. Participants: Prospective and retrospective studies, excluding reviews, which included patients with head and neck squamous cell carcinoma who had fluorodeoxyglucose PET in the post-treatment phase following primary treatment by radiotherapy or chemoradiotherapy. Main outcomes measures: Quality assessment, sensitivity, specificity, false positive rates, false negative rates, positive and negative predictive values. Results: Twenty-seven of 1871 identified studies were eligible for inclusion. The pooled sensitivity and specificity of PET for detecting residual or recurrent head and neck squamous cell carcinoma were 94% [95% confidence interval (CI), 87-97%] and 82% (95% CI, 76-86%) respectively. Positive and negative predictive values were 75% (95% CI, 68-82%), and 95% (95% CI, 92-97%) respectively. Sensitivity was greater for scans performed 10 weeks or more after treatment. Conclusions: Positron emission tomography is highly accurate in this role. However it is less sensitive early after treatment and has poor anatomical detail. PET may reduce the requirement for check endoscopies and planned neck dissections. A protocol for its use in post-treatment surveillance is proposed.