A woman in her 70s was referred for assessment of a swelling affecting the left inferior labial mucosa. Slow enlargement had occurred over 2 years, but the appearance had been stable over the past several months. There was no associated tenderness or paresthesia. There was no history of any recent trauma.
On examination, the lesion was a soft submucosal nodule surfaced by unremarkable pink mucosa and measured 15 mm in the greatest dimension (Figure, A). There was no cervical lymphadenopathy. Incisional biopsy revealed deep submucosal infiltration by both nested and individual cells with vacuolated cytoplasmic clearing and nuclear scalloping reminiscent of lipoblasts (Figure, B and C). There were some admixed mature adipocytes. Mitotic figures and necrosis were not identified. No foreign material was seen histologically.