Pleomorphic Hyalinising Angiectatic Tumour: A Tumour Diagnosis of Suspicion

Abstract

A 62 year old male was referred to our service complaining of a 5 year history of a painful, erythematous swelling on the proximal third of his right tibia. A previous MRI scan displayed appearances suggested to be consistent with fat necrosis, erythema nodosum or pretibial myxoedema. On examination there was an ill-defined, soft, subcutaneous mass on the right anterior leg measuring approximately 30mm x 40mm in diameter. The overlying skin was warm to palpation and mildly tender but with no epidermal changes. There were no associated neurovascular signs or lymphadenopathy. An incisional biopsy revealed histological features highly suggestive of Pleomorphic Hyalinizing Angiectatic Tumour (P.H.A.T). Wide local excision of 3cm margin (90 x 85mm) was subsequently performed with split skin graft reconstruction. The patient remains recurrence-free at 1 year post surgery. Pleomorphic Hyalinizing Angiectatic Tumour is an unusual, highly vascular soft tissue tumour, usually occurring in the subcutis of the lower extremity. Differential diagnoses include neurilemoma and malignant fibrous histiocytoma and, as illustrated by this case report, erythema nodosum or even pretibial myxoedoema. Clinical suspicion of PHAT should initiate MRI scan and incision biopsy. Current literature suggests that, due to a 20-33% rate of local recurrence, P.H.A.T should be treated by wide local excision by a 3cm margin and is to include deep fascia, down to periosteum. It should be reviewed regularly as reports of multiple recurrences 25 years after excision suggest that life-long review may be prudent.




J Med Cases. 2012;3(6):334-336
doi: https://doi.org/10.4021/jmc573w