Fibrous xanthomas and xanthosarcomas of the meninges and the brain

Summary

Three cases of intracranial fibrous xanthomas and a case of multicentric cerebral xanthosarcoma are reported. All three fibrous xanthomas developed in the temporal area of boys in their early teens, one was within the leptomeninges (without dural attachment), the other two involved meninges and the superficial portions of the temporal lobe itself. These tumors were characterized by mono- and multinucleated cells with morphological features of histiocytes, Touton type giant cells and a “storiform pattern” in areas of spindleshaped tumor cells.

Because of cellular atypism, giant cells and mitotic figures such tumors may suggest the diagnosis of glioblastoma multiforme but the absence of glial fibers, negative Cajal impregnation, presence of reticulin fibers in close proximity to tumor cells and the morphological similarity to the bizarre cells found in atypical xanthofibromas of the skin and soft tissues help to establish the diagnosis. Since the menigeal forms are probably derived from local meningeal mesenchyme, occasional abortive whorls and pseudopsammoma bodies may be encountered, the overall picture, however, is very different from meningiomas. Two patients had a 2.5 and a 12 year long symptomfree survival, respectively. The third boy had a local recurrence 14 months after initial removal which was excised and the patient is presently doing well.

The xanthosarcoma first developed in the right frontal lobe of a 26 year old woman. This tumor was almost exclusively made up of various sized anaplastic cells filled with birefringent lipids. It is suggested that this tumor which had a diffuse network of reticulin, had originated from primitive adventitial cells. It was histologically more malignant than the first three and the patient died within a year after removal of the frontal lobe tumor, from a second mass in the cerebellum. The relationship of this tumor to glioblastomas and to other types of giant cell sarcomas is discussed.