2022 Volume 21 Issue 4 Pages 321-327
A 67-year-old woman with a mass in the back of her head since 40 years ago was referred to our department because the mass had gradually increased in size. An elastic, soft, subcutaneous mass of tennis ball size with slightly poor mobility was found in the occipital region. Ultrasonography revealed a spindle-shaped hypoechoic mass with some linear hyperechoic areas inside, and lipoma was suspected with some depression of the skull. Increased blood flow was also noted at the same site. CT and MRI revealed that although the skull outer plate in contact with the mass was partially lost, the inner plate remained and no intracranial extension was observed. Tissue biopsy diagnosed the mass as a lipoma, and total excision was performed. After five years follow-up, there has been no local recurrence. Intraosseous lipoma is a rare bone tumor. We considered that the intraosseous lipoma had developed within the crown of the skull, destroyed the outer plate, and expanded subcutaneously. To the best of our knowledge, 14 cases of intraosseous lipomas have been reported within the cranial cap, and only one of themwas accompanied by bone destruction ;thus, the present case is an extremely rare occurrence. Skin Research, 21 : 321-327, 2022
