Kwon MR, et al. - The researchers intended to assess the feasibility of greyscale ultrasound (US) and histogram analysis in differentiating the subtypes of the papillary thyroid carcinoma (FVPTC). Greyscale histogram analysis was found to be feasible for differentiating non-invasive follicular thyroid neoplasm with papillary-like nuclear feature (NIFTP) from infiltrative FVPTC, but not NIFTP from invasive encapsulated FVPTC (EFVPTC). To differentiate the subtypes of FVPTC, histograms could be used as a supplementary tool.