Is sonographic intra-nodular vascularity a reliable predictor of thyroid malignancy? A UK tertiary centre study.

OBJECTIVE: British Thyroid Association 2014 guidelines emphasised ultrasound assessment of nodules. One ultrasonographic differentiator of debatable relevance is intra-nodular vascularity. This is the first UK study conducted to address this question. METHODS: Ultrasound reports for thyroid surgery patients over 10 years were retrospectively reviewed. Reports documenting 'intra-nodular vascularity or flow' were analysed. Reports identifying peripheral vascularity only or no intra-nodular flow formed the control group. Concordance with final histology was used to determine the odds ratio for malignancy. RESULTS: A total of 306 patients were included, and 119 (38.9 per cent) nodules demonstrated intra-nodular vascularity. Of these, 60 (50.4 per cent) were malignant compared with 42 per cent in the control group. Intra-nodular vascularity was not a statistically significant predictor of malignancy with an odds ratio of 1.39 (p = 0.18, 95 per cent confidence interval, 0.86-2.23). CONCLUSION: Intra-nodular vascularity in isolation was not a reliable predictor of malignancy. This supports other world literature studies. Although intra-nodular flow should not be relied upon in isolation, interpretation in conjunction with other suspicious findings enhances the predictive value.