Hybrid peripheral nerve sheath tumours: MRI features with pathological correlation in 24 cases.

Objectives: To describe the MRI features of histologically proven hybrid peripheral nerve sheath tumours (HPNST).

Methods: A retrospective analysis of the MRI features of 24 histologically proven cases of HPNST over 7 years. Demographic data obtained from clinical records included age, gender, and date of diagnosis.

Dermatofibrosarcoma protuberans: the diagnosis of high-grade fibrosarcomatous transformation.

Objectives: Dermatofibrosarcoma protuberans (DFSP) is an intermediate-grade tumour which may undergo fibrosarcomatous transformation to a high-grade sarcoma (DFSP-FST). DFSP-FST requires wide local resection, and therefore, pre-operative identification is important. The aims of this study are to see if DFSP and DFSP-FST can be differentiated based on MRI appearances, and to determine the ability of ultrasound-guided core needle biopsy (US-CNB) to identify DFSP-FST.