#### What you need to know A 45 year old woman presented to her general practitioner several times over nine months with a gradually enlarging, hard lump in her anterior thigh. An ultrasound scan showed a solid intramuscular mass in the anterior compartment of her thigh, prompting a two week wait referral to the regional sarcoma diagnostic clinic. Magnetic resonance imaging showed a large, heterogeneous intramuscular mass. Core biopsy confirmed a high grade soft tissue sarcoma, and staging computed tomography showed lung metastases. The patient underwent chemotherapy for metastatic disease, followed by resection of her primary tumour, but her disease relapsed and she died 16 months after diagnosis. Soft tissue sarcoma is a heterogeneous group of malignancies. They account for 1% of cancers and have a five year survival of approximately 50%. They can occur at any age (although more than 65% occur in people aged over 50 years1) and in any part of the body. #### How common are soft tissue sarcomas?