A pomegranate heart

Sacrococcygeal teratomas are common in infants while a buttock terotoma is extremely rare in adults. Herein we report a 30-year-old female complaining of left hip swelling and pain for 2 weeks. Ultrasonography demonstrated a subcutaneous cystic mass with multiple dense echo spots inside. MR showed a heart-shaped mass in the left buttock, with multiple "pomegranate seeds" inside, which showed hyperintensity on diffusion weighted imaging. The mass was resected and a buttock terotoma containing yellow sebum-like materials and hairs was confirmed pathologically. A thick walled cystic mass on CT or MR images, which contains multiple small solid nodules or fat, indicates the diagnosis of a terotoma. Timely diagnosis and complete resection bring good prognosis. Adequate follow-up is necessary.