出血で発症し髄腟内播種性転移のみられた小脳Glioblastomaの1剖検例

Glioblastoma of the Cerebellum:Report of an autopsy case associated with intratumoral hemorrhage and CSF seedings

I．はじめに

　glioblastoma multiformeは成人大脳半球に好発する最も悪性な脳腫瘍の一つであり，従来テント下，特に小脳に原発するものは極めて稀と考えられていた^29）．近年小脳原発のglioblastomaの報告数は増えてきてはいるが不明な点も未だ少なくない．今回われわれは腫瘍内出血で発症し，短期間に局所再発．髄腔内播種性転移のみられた小脳ghoblastomaの1剖検例を経験したので，若干の文献的考察を加え報告する．

Abstract

An autopsy case of glioblastoma of the cerebellum associated with an intracerebellar hemorrhage and showing CSF seedings is reported. A 26 year-old male was admitted to our hospital with a 10-day history of headache, nausea and vertigo. On admission, disturb-ance of consciousness (10 - 20 by JCS) , irregular re-spiration and central fixation of both eyes suggesting increased intracranial pressure and early stage of cen-tral herniation were recognized clinically. The cerebel-lar signs of dysmetria and nystagmus were also observed. CT scan and angiography revealed an avascular large mass in the right cerebellar hemisphere, obstructive hydrocephalus and upward transtentorial herniation. On MRI study, the mass was demonstrated to be a subacute hematoma with a small tumor in its margin. Total removal of the tumor and aspiration of the hematoma were performed. Histological examina-tion revealed a highly cellular and pleomorphic astrocy-tic tumor with scattered small necrosis and glomeruloid capillary endothelial proliferation, typical of glioblasto-ma multiforme. During postoperative radiochemothera-py (focal irradiation to the posterior fossa) , the tumor showed rapid regrowth and a second look operation was performed. He was readmitted 3 weeks after radiochemotherapy with complaints of severe headache, nausea and lumbago. He then suddenly became dys-peneic, tetraplegic and bradycardic. Neuroradiologicalinvestigation revealed multiple masses in the suprasel-lar region, medulla oblongata and the cervical spinal cord, but no recurrence in the cerebellum. Malignant cells were noted on CSF cytology. During chemothera-py for CSF tumor dissemination, his condition deterio-rated rapidly and he died 7 months after the onset of symptoms. Autopsy revealed multiple tumors in the hy-pothalamus, medulla oblongata and cervical, thoracic and lumbar spinal cord. CSF seedings were cofirmed and no reccurent tumor was observed in the cere-bellum.

Glioblastoma multiforme of the cerebellum is rare (approximately L9% of all glioblastomas) and its clinic-al course and pathological findings are similar to those in the cerebrum. Though local infiltration is reported as the main growth pattern of glioblastoma of the cerebel-lum, CSF seeding, seen in our case, has also been re-ported as a metastatic route of cerebellar glioblastoma.