What Is Soft Tissue Sarcoma?
Soft tissue sarcomas are a rare and varied group of cancers arising from connective tissues — including fat, muscle, fibrous tissue, and blood vessels — that can occur in or beneath the skin. They are much rarer than BCC, SCC or melanoma, and because of this rarity, together with their varied appearance, diagnosis can sometimes be delayed. Awareness of the "red-flag" features below, and referral to a specialist sarcoma centre when they are present, is central to good outcomes.
Red-Flag Features
Any lump with the following features should be assessed promptly, in line with NICE guideline NG12 suspected sarcoma referral criteria:
- Larger than 5cm in diameter
- Increasing in size
- Deep to the muscle fascia, or fixed to deeper structures
- Painful
- A lump that has recurred after previous removal
Any one of these features alone is reason enough for urgent assessment and imaging.
Diagnosis: Imaging Before Biopsy
For a lump with any red-flag feature, imaging (usually MRI) should be arranged before any biopsy or excision is attempted. Biopsying or removing a suspicious lump without prior imaging can contaminate the surrounding tissue planes with tumour cells, compromising the ability to achieve clear margins at definitive surgery later, and should be avoided.
Where imaging is suspicious, a core needle biopsy (rather than an excisional biopsy) is performed, ideally at, or in direct discussion with, a specialist sarcoma centre, so that the biopsy tract itself can be planned to be excised along with the tumour at definitive surgery if needed.
Treatment
Management of confirmed soft tissue sarcoma is coordinated through a specialist sarcoma multidisciplinary team (MDT) at a designated sarcoma centre, and typically involves:
- Wide local excision — removing the tumour with a margin of normal tissue in all directions, planned according to the specific imaging findings
- Radiotherapy — often used as an adjunct to surgery, particularly for larger or higher-grade tumours, to reduce the risk of local recurrence
- Chemotherapy — reserved for selected high-grade or advanced cases, guided by the sarcoma subtype
- Reconstruction — planned according to the resulting defect, which can be substantial for larger tumours, often requiring flap reconstruction
Why Specialist Centre Management Matters
Because soft tissue sarcomas are rare and highly varied in behaviour, treatment at a designated specialist sarcoma centre — where cases are reviewed by a dedicated sarcoma MDT — is associated with better outcomes than management outside this pathway. Where a suspicious lump is identified, prompt referral into this specialist pathway, rather than local excision, is the safest first step.
Related Pages
- Dermatofibrosarcoma Protuberans (DFSP)
- Skin Cancer Excision & Reconstruction
- Reconstructive Techniques: Skin Grafts & Flaps