["To propose a novel measure, namely the 'asphericity' (ASP), of spatial irregularity of FDG uptake in the primary tumour as a prognostic marker in head-and-neck cancer.", "PET/CT was performed in 52 patients (first presentation, n\u2009=\u200936; recurrence, n\u2009=\u200916). The primary tumour was segmented based on thresholding at the volume-reproducible intensity threshold after subtraction of the local background. ASP was used to characterise the deviation of the tumour's shape from sphere symmetry. Tumour stage, tumour localisation, lymph node metastases, distant metastases, SUVmax, SUVmean, metabolic tumour volume (MTV) and total lesion glycolysis (TLG) were also considered. The association of overall (OAS) and progression-free survival (PFS) with these parameters was analysed.", 'Cox regression revealed high SUVmax [hazard ratio (HR)\u2009=\u20094.4/7.4], MTV (HR\u2009=\u20094.6/5.7), TLG (HR\u2009=\u20094.8/8.9) and ASP (HR\u2009=\u20097.8/7.4) as significant predictors with respect to PFS/OAS in case of first tumour manifestation. The combination of high MTV and ASP showed very high HRs of 22.7 for PFS and 13.2 for OAS. In case of recurrence, MTV (HR\u2009=\u20093.7) and the combination of MTV/ASP (HR\u2009=\u20094.2) were significant predictors of PFS.'] Does asphericity of pretherapeutic tumour FDG uptake provide independent prognostic value in head-and-neck cancer?