Massive vulval edema secondary to obesity and immobilization: a potential mimic of aggressive angiomyxoma

We report 2 cases of surgically resected vulval masses in women aged 27 and 40 years. One patient was wheelchair bound and the other was obese, both presented with bilateral vulvar swelling. One specimen measured 45 cm in maximum dimension and the other 5 cm and were described as grossly edematous or gelatinous. Histologically, in both cases, there was edema of the skin overlying the lesion. The lesion itself consisted of markedly edematous connective tissue with widely separated bland spindle-shaped cells and numerous dilated vascular channels, sometimes surrounded by cuffs of lymphocytes and plasma cells. In the larger of the 2 specimens, underlying edematous adipose tissue was present. To some extent, the appearances, especially the morphological features, mimicked aggressive angiomyxoma because of the presence of a mass, the lack of circumscription, the hypocellular, edematous appearance, and the presence of numerous vascular channels. However, a combination of clinical and pathological features, including bilateralism, lack of a true myxoid stroma, the presence of perivascular cuffs of lymphoid cells, and lack of staining with estrogen receptor, is against aggressive angiomyxoma. The appearances were interpreted as those of massive edema. In one case, there was recurrence of the mass after surgery. There has been a single previous report of a similar vulvar case in a quadriplegic female patient and of similar cases involving the upper and lower extremities of obese patients. Clinicians and pathologists should be aware of the existence of this lesion, which is likely due to lymphatic obstruction and lymphedema secondary to immobilization and obesity.