On lipoma of the buccal fat pad: report of two cases and review of the literature.

The buccal fat pad (BFP) has been the subject of numerous publications regarding its anatomy and clinical implications, however our interest in the pathology was aroused by two cases of lipoma originating from the BFP that were particularly interesting as one lipoma was congenital and the other recurred. A search of the international literature revealed a further 27 cases of BFP lipoma dating from 1848 to 2002. This suggests it is a rare entity but the authors suspect it to be under reported because of unfamiliarity with the possibility and the various atypical characteristics that were observed. Firstly, BFP lipomas appear to be congenital relatively often. Also, many are histological variants such as the spindle-cell lipoma, which could be associated with a more diffuse growth in the various extensions. As the deep extensions are not routinely removed due to the difficulty of the procedure, this could result in incomplete resection and recurrence. A possible explanation is the hypothesis that the BFP has a different embryological origin than subcutaneous fat. More importantly, well-differentiated liposarcoma of the BFP has also been described, which may be clinically and histologically indistinguishable from spindle-cell lipoma. Therefore, the authors recommend a careful workup of every mass of the buccal space with consideration of the BFP as a possible origin. Detailed knowledge of the anatomy and extensive MR-imaging are paramount in guiding the surgical approach by visualising the extent of growth in the various extensions, and determining if the radiological picture is suggestive of liposarcoma.