Severity classification of Tenosynovial Giant Cell Tumours on MR imaging.

•TGCT describes a very heterogeneous entity with clear differences in clinical outcome related to recurrence free survival.•A combination of four MR parameters, resulting in four TGCT severity subgroups, discriminates for TGCT severity on MR imaging.•Definition of the most severe TGCT subgroup attributes to the identification of eligible patients for targeted therapy.