Background: Spindle cell/pleomorphic lipoma (SC/PL) is a benign adipose tissue tumor that usually affects the subcutaneous tissues of shoulders, backs, and neck region of middle-aged male patients. Histologically, it is characterized by the presence of primitive CD34-positive spindle cells arranged in short fascicles, bizarre floret-like multinucleated giant cells, mature adipocytes, and a small number of lipoblasts. Recently, an intradermal subset has been described, which mainly affects female patients and presents a wider antomical distribution when compared to the classical variant of SC/PL.

Methods: We report a case of intradermal SC/PL affecting the labium majus of a 56-year-old female patient.

Results: The histological examination disclosed the typical histological features, however the lesion showed poorly demarcated and infiltrative borders, as well as involvement of dermal nerves. The immunohistochemical analysis according to streptovidin-biotin-peroxidase technique showed immunoreactivity for CD34 and vimentin in the spindle cells, as well as S100 protein and vimentin in the adipocytic cells.

Conclusions: To the best of our knowledge, this is the first case of intradermal SC/PL affecting the vulvar region. Care must be taken not to misdiagnosis this rare tumor as well-differentiated liposarcoma, cellular angiofibroma, solitary fibrous tumor, and cutaneous neurofibroma.