Double aggressive osteoblastomas of calvarium

A 55-year-old female presented with a painful protruding mass in right parietal skull for 7 months. Interestingly, another smaller bony lesion, separated from the symptomatic one, was disclosed in right frontal skull on imaging study. The larger one was completely excised, first with a picture of an aggressive osteoblastoma in the pathology. The smaller one in the frontal skull was excised subsequently, presenting the same pathological picture as the larger one. No other foci of osteoblastomas were detected on the whole body bone scan. To our knowledge, this is the first case with double independent osteoblastomas occurring in frontal and parietal skull. Surgical strategy for these two bony lesions was discussed.