A pragmatic approach to lipomatous tumours of the limbs and trunk wall

Soft tissue lipomatous lesions of the limbs and trunk wall are commonly referred to sarcoma services for specialist advice on diagnosis and management. The rates of such referrals place considerable strain on sarcoma multidisciplinary teams (MDTs) and are often unnecessary where lesions demonstrate no concerning features on imaging. The aim of this study was to retrospectively evaluate the referral rates and MDT outcomes for soft tissue lipomatous lesions of the limbs and trunk wall.

Data were retrospectively collected for referrals to a single specialist sarcoma centre based in the UK over a 12-month period.

350 fat-containing soft tissue lesions of the limbs and trunk wall were referred to the sarcoma service. Over two-thirds of lesions (242/350, 69.1 %) were solitary subcutaneous or intra/intermuscular lipomas with homogeneous fat signal on MRI. Twenty-one lesions (6.0 %) required percutaneous core needle biopsy. Only 2.0 % (7/350) of referrals constituted high grade liposarcomas. The authors present a new protocol entitled Birmingham Lipomatous Tumour Imaging Protocol (BLTIP) to guide referral of first-presentation soft tissue lipomatous tumours of the limbs and trunk wall based solely on MRI appearances. This approach emphasises the role of local radiologists in assessing lesions on MRI prior to sarcoma service referral. Homogeneously fatty lesions on MRI do not qualify for referral to the sarcoma service. Based on the retrospective dataset, this protocol reduced the number of benign referrals by up to three quarters without preventing referral of any liposarcomas.

Implementation of alternative referral protocols such as the one proposed would reduce the rates of overtly benign lipomatous lesions currently referred to sarcoma services.