[TNM Classification of malignant tumours - Eighth edition: which news?].

The eighth edition of TNM classification of malignant tumours has been published by the Union for International Cancer Control in January 2017. As for the previous editions - from the third on - it has been translated into Italian and recently published in our Country. This article explains the main changes from the previous edition: new classifications, some major revisions of cancer staging rules, the introduction of a grid of prognostic factors for each neoplasia and the addition of two chapters. These two chapters are about the essential TNM and the paediatric tumours, and have been developed in order to facilitate the use of data by Cancer Registries.