Neuroradiolngg
Neuroradiology 17, 219-222 (1979)
© by Springer-Verlag 1979
Unusual Metastases from a Medulloblastoma: Case Report E. Palacios, M. Shannon and M. Fine Department of Radiology, Loyola Uniw~rsityMedical Center, Maywood, Illinois, USA
Summary. Calvarial and extracranial metastases by hematogenous spread of primary intracranial neoplasms have been considered a rare occurrence. This report deals with the clinicopathological and radiological findings of a child with metastatic medulloblastoma. Correlation of serial, postoperative computed tomography (CT) scans and the autopsy examination indicated hematogenous calvarial and intracranial spread of the primary lesion.
removal was not possible. The patient was irradiated after operation with 4986 rads to the posterior fossa, 4050 rads to the upper spinal canal, and 3900 rads to the supratentorial area and lower spinal canal. His progress was satisfactory until a year later when he developed a seizure and struck his head. Skull films revealed a linear parietal fracture. An
Key words: Metastases - Medulloblastoma - Computed tomography
Case Report A male child, aged 6, was transferred to Loyola University Medical Center with a progressive history of nausea, vomiting and headaches. A gastrointestinal study at another hospital had been normal. Papilledema was noted, which prompted an angiogram. This demonstrated a large midline posterior fossa mass causing a marked degree of obstructive hydrocephalus. The calvarium was intact at this time. A water-soluble contrast (Conray) ventriculogram confirmed obstruction of the proximal portion of the aqueduct of Sylvius by a large midline cerebellar mass. CT performed without contrast infusion confirmed a large posterior fossa mass in the midline, obliterating the fourth ventricle and producing marked hydrocephalus. The tumor mass was somewhat denser than the surrounding brain. At operation a large mass, which proved to be a medulloblastoma, was partially removed from the cerebellum. The mass was thought to extend anteriorly into the medulla oblongata and complete
Fig. la and h. Precontrast scan shows dense bifrontal lesions and edema compressing frontal horns, e and d The masses enhance. Scan plane is more angled and occipitalbone thickeningis present
0028-3940/79/0017/0219/$01.00
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E. Palacios et al.: Unusual Metastases from Medulloblastoma
ated with a dense mass extending intracranially. The lateral skull X-ray (Fig. 3) at this time showed sclerotic bone thickening of the occiput. The patient lapsed into coma and died about 20 months after initial admission. Two large intraparenchymal frontal lobe masses were confirmed at autopsy. No tumor was found within the ventricles and the masses appeared to be entirely demarcated from the ventricles and subarachnoid spaces. The mass in the posterior fossa appeared to be arising from bone, but involved the meninges and extended into the left cerebellar hemisphere (Fig. 4).
Discussion
Fig. 2. Precontrast a and b and post contrast scans c and d show that bifrontal masses have enlarged; there is now a posterior fossa mass. e and f Bone window settings show bony thickening and soft tissue involvement in occipital region
osteoblastic area involving the left occipital bone was noted at that time. CT (Fig. 1) revealed bifrontal enhancing masses with some edema and slight compression of the frontal horns. The ventricles were not enlarged. The fourth ventricle was well visualized and there was no evidence of recurrent posterior fossa tumor, but the calvarium on the left side of the posterior fossa was markedly thickened. The general status of the patient deteriorated rapidly within 4 months. Chemotherapy had no significant clinical effect. The third C-F scan (Fig. 2) showed further enlargement of the frontal masses, marked hydrocephalus, and more extensive thickening of the calvarium in the left posterior fossa associ-
Medulloblastomas are known to spread by seeding from the posterior fossa through the cerebrospinal fluid pathways, or retrograde into the ventricular system, implanting and growing through the parenchyma into the brain, particularly after shunting. In our case the postoperative CT demonstrated the frontal lobe metastases to be purely intraparenchymal rather than of ventricular or arachnoidal origin, as confirmed by autopsy. Lymphatic spread was ruled out by the fact that lymphatic vessels are not present in the brain parenchyma [1]. It is thus presumed that the metastatic lesions spread hematogenously. It is possible that the calvarial tumor was an extension of a recurrence of the primary tumor; nevertheless the CT indicated bone involvement with intracranial extension. Although implantation could have occurred at operation, the possibility that the route of the osseous metastasis was also hematogenous must be considered. Metastasis from medulloblastoma outside the central nervous system is a rare occurrence, although at least 60 cases have now been reported [2]. Many of those, however, did not fulfill the four criteria proposed by Weiss as proof of extracerebral metastases from intracranial tumors, i. e.: (1) a single histologically characteristic tumor of the central nervous system was identified; (2) initial symptoms were due to this tumor; (3) a full autopsy was performed to rule out the possibility of any other primary site; (4) the morphology of the metastasis and the primary tumor were identical [3]. In the present case, the presenting symptoms were definitely attributable to a histologically characteristic medulloblastoma. The calvarial metastatic lesion was microscopically identical to the primary neoplasm, and an extensive autopsy failed to reveal a primary tumor elsewhere that could account for the metastatic lesions of the skull. Aside from a single case report [4], all previously reported metastatic foci outside the central nervous
E. Palacios et al.: Unusual Metastases from Medulloblastoma
221
Fig. 3. Extensive sclerosis of occipital bone and extension into soft tissues, seen on lateral skull Xray
system from primary intracranial neoplasms have been first noted after operation. In this respect, our case is no exception. Osteoblastic bone metastases from medulloblastoma are not uncommon and some of them have occurred after radiation therapy for symptomatic osteolytic lesions [5]. Since the entire central nervous system was irradiated after operation this may have predisposed to the blastic calvarial metastatic focus in our case. The CT appearances of medulloblastoma have been well documented [6, 7, 8, 9, 10, 11]. They are most often more dense than surrounding brain tissue with a range of 46.6 Hounsfield units (23.3 EMI units), and enhance an average of 16 Hounsfield units with contrast infusion. The primary lesion in our case demonstrated an absorption coefficient in the range of that previously reported, and the frontal lobe metastatic foci were of a similar density; these enhanced markedly with contrast infusion. Enzman, et al. recently described the CT appearances of a series of metastatic medulloblastomas [12] but none of these were intraparenchymal or involved the calvarium. Zimmerman, et al. stressed the importance of post-operative followup by CT to detect recurrence or spread via cerebrospinal fluid pathways to other areas of the brain [6]. CT contri-
Fig. 4. Pathological specimen with bifrontal intraparenchymal masses and intra-axial posterior fossa mass
222 b u t e d i m p o r t a n t i n f o r m a t i o n in the p r e o p e r a t i v e e v a l u a t i o n of o u r p a t i e n t ; p o s t o p e r a t i v e l y , C T was essential i n assessing the m e t a s t a t i c process.
References 1. Winkleman, N.W., Cassel, C., Schlesinger, B. J.: Intracranial tumors with extracranial metastases. J. Neuropathol. Exp. Neurol. 11, 149-168 (1952) 2. Brutsckin, P., Calvin, G.: Extracranial metastases from medulloblastomas. Radiology 107, 359-362 (1973) 3. Weiss, Z.: Metastasizing ependymoma of cauda equina. Cancer 8, 161-171 (1955) 4. Rubinstein, L.J.: Development of extracranial metastases from a malignant astrocytoma in the absence of previous craniotomy. Case report J. Neurosurg. 26, 542-547 (1967) 5. Lewis, M.B., Nuses, L.B., Powell, D.E., Sheriden, B.I.: Extra-axial spread of medulloblastoma. Cancer 31, 1287-1297 (1973) 6. Zimmerman, R.A., Bilaniuk, Z.T., Pahlajani, H.: Spectrum of medulloblastomas demonstrated by computed tomography. Radiology 126, 137-141 (1978) 7. Gado, M., Huete, I., Mickael, M.: Computerized tomography of intratentorial tumors. Semin. Roentgenol. 12, (1977)
E. Palacios et al.: Unusual Metastases from Medulloblastoma 8. Naidich, T.P., Lin, J.P., Leeds, N.E., Pudlowski, R.M., Naidich, J. B.: Primary tumors and other masses of the cerebellum and fourth ventricle differential diagnosis by computed tomography. Neuroradiology 14, 153-174 (1977) 9. Kazner, E., Aulich, A., Grumme, T.: Results of computerized axial tomography with infratentorial tumors. In: Cranial computerized tomography (eds. W. Lanksch, E. Kazner). pp. 90-103. New York: Springer 1976 10. Wilson, J. L., Moseley, I. F.: A diagnostic approach to cerebellar lesions. In: Computerized axial tomography in clinical practice (eds. G.H. du Boulay, I. F. Moseley), pp. 123-133. New York: Springer 1977 11. Gonzalez, C.F., Grossman, C.B., Palacios, E.: Computed brain and orbital tomography: technique and interpretation, pp. 129-134. New York: Wiley 1976 12. Enzman, D. R., Norman, D., Levin, V., Wilson, C., Newton, T. H.: Computed tomography in the follow-up of medulloblastomas and ependymomas. Radiology 128, 57-64 (1978) Received: 4 December 1978 Dr. E. Palacios Department of Radiology Loyola University Medical Center 2160 South First Avenue Maywood, IL 60153, USA
Neuroradiology 17, 219-222 (1979)
© by Springer-Verlag 1979
Unusual Metastases from a Medulloblastoma: Case Report E. Palacios, M. Shannon and M. Fine Department of Radiology, Loyola Uniw~rsityMedical Center, Maywood, Illinois, USA
Summary. Calvarial and extracranial metastases by hematogenous spread of primary intracranial neoplasms have been considered a rare occurrence. This report deals with the clinicopathological and radiological findings of a child with metastatic medulloblastoma. Correlation of serial, postoperative computed tomography (CT) scans and the autopsy examination indicated hematogenous calvarial and intracranial spread of the primary lesion.
removal was not possible. The patient was irradiated after operation with 4986 rads to the posterior fossa, 4050 rads to the upper spinal canal, and 3900 rads to the supratentorial area and lower spinal canal. His progress was satisfactory until a year later when he developed a seizure and struck his head. Skull films revealed a linear parietal fracture. An
Key words: Metastases - Medulloblastoma - Computed tomography
Case Report A male child, aged 6, was transferred to Loyola University Medical Center with a progressive history of nausea, vomiting and headaches. A gastrointestinal study at another hospital had been normal. Papilledema was noted, which prompted an angiogram. This demonstrated a large midline posterior fossa mass causing a marked degree of obstructive hydrocephalus. The calvarium was intact at this time. A water-soluble contrast (Conray) ventriculogram confirmed obstruction of the proximal portion of the aqueduct of Sylvius by a large midline cerebellar mass. CT performed without contrast infusion confirmed a large posterior fossa mass in the midline, obliterating the fourth ventricle and producing marked hydrocephalus. The tumor mass was somewhat denser than the surrounding brain. At operation a large mass, which proved to be a medulloblastoma, was partially removed from the cerebellum. The mass was thought to extend anteriorly into the medulla oblongata and complete
Fig. la and h. Precontrast scan shows dense bifrontal lesions and edema compressing frontal horns, e and d The masses enhance. Scan plane is more angled and occipitalbone thickeningis present
0028-3940/79/0017/0219/$01.00
220
E. Palacios et al.: Unusual Metastases from Medulloblastoma
ated with a dense mass extending intracranially. The lateral skull X-ray (Fig. 3) at this time showed sclerotic bone thickening of the occiput. The patient lapsed into coma and died about 20 months after initial admission. Two large intraparenchymal frontal lobe masses were confirmed at autopsy. No tumor was found within the ventricles and the masses appeared to be entirely demarcated from the ventricles and subarachnoid spaces. The mass in the posterior fossa appeared to be arising from bone, but involved the meninges and extended into the left cerebellar hemisphere (Fig. 4).
Discussion
Fig. 2. Precontrast a and b and post contrast scans c and d show that bifrontal masses have enlarged; there is now a posterior fossa mass. e and f Bone window settings show bony thickening and soft tissue involvement in occipital region
osteoblastic area involving the left occipital bone was noted at that time. CT (Fig. 1) revealed bifrontal enhancing masses with some edema and slight compression of the frontal horns. The ventricles were not enlarged. The fourth ventricle was well visualized and there was no evidence of recurrent posterior fossa tumor, but the calvarium on the left side of the posterior fossa was markedly thickened. The general status of the patient deteriorated rapidly within 4 months. Chemotherapy had no significant clinical effect. The third C-F scan (Fig. 2) showed further enlargement of the frontal masses, marked hydrocephalus, and more extensive thickening of the calvarium in the left posterior fossa associ-
Medulloblastomas are known to spread by seeding from the posterior fossa through the cerebrospinal fluid pathways, or retrograde into the ventricular system, implanting and growing through the parenchyma into the brain, particularly after shunting. In our case the postoperative CT demonstrated the frontal lobe metastases to be purely intraparenchymal rather than of ventricular or arachnoidal origin, as confirmed by autopsy. Lymphatic spread was ruled out by the fact that lymphatic vessels are not present in the brain parenchyma [1]. It is thus presumed that the metastatic lesions spread hematogenously. It is possible that the calvarial tumor was an extension of a recurrence of the primary tumor; nevertheless the CT indicated bone involvement with intracranial extension. Although implantation could have occurred at operation, the possibility that the route of the osseous metastasis was also hematogenous must be considered. Metastasis from medulloblastoma outside the central nervous system is a rare occurrence, although at least 60 cases have now been reported [2]. Many of those, however, did not fulfill the four criteria proposed by Weiss as proof of extracerebral metastases from intracranial tumors, i. e.: (1) a single histologically characteristic tumor of the central nervous system was identified; (2) initial symptoms were due to this tumor; (3) a full autopsy was performed to rule out the possibility of any other primary site; (4) the morphology of the metastasis and the primary tumor were identical [3]. In the present case, the presenting symptoms were definitely attributable to a histologically characteristic medulloblastoma. The calvarial metastatic lesion was microscopically identical to the primary neoplasm, and an extensive autopsy failed to reveal a primary tumor elsewhere that could account for the metastatic lesions of the skull. Aside from a single case report [4], all previously reported metastatic foci outside the central nervous
E. Palacios et al.: Unusual Metastases from Medulloblastoma
221
Fig. 3. Extensive sclerosis of occipital bone and extension into soft tissues, seen on lateral skull Xray
system from primary intracranial neoplasms have been first noted after operation. In this respect, our case is no exception. Osteoblastic bone metastases from medulloblastoma are not uncommon and some of them have occurred after radiation therapy for symptomatic osteolytic lesions [5]. Since the entire central nervous system was irradiated after operation this may have predisposed to the blastic calvarial metastatic focus in our case. The CT appearances of medulloblastoma have been well documented [6, 7, 8, 9, 10, 11]. They are most often more dense than surrounding brain tissue with a range of 46.6 Hounsfield units (23.3 EMI units), and enhance an average of 16 Hounsfield units with contrast infusion. The primary lesion in our case demonstrated an absorption coefficient in the range of that previously reported, and the frontal lobe metastatic foci were of a similar density; these enhanced markedly with contrast infusion. Enzman, et al. recently described the CT appearances of a series of metastatic medulloblastomas [12] but none of these were intraparenchymal or involved the calvarium. Zimmerman, et al. stressed the importance of post-operative followup by CT to detect recurrence or spread via cerebrospinal fluid pathways to other areas of the brain [6]. CT contri-
Fig. 4. Pathological specimen with bifrontal intraparenchymal masses and intra-axial posterior fossa mass
222 b u t e d i m p o r t a n t i n f o r m a t i o n in the p r e o p e r a t i v e e v a l u a t i o n of o u r p a t i e n t ; p o s t o p e r a t i v e l y , C T was essential i n assessing the m e t a s t a t i c process.
References 1. Winkleman, N.W., Cassel, C., Schlesinger, B. J.: Intracranial tumors with extracranial metastases. J. Neuropathol. Exp. Neurol. 11, 149-168 (1952) 2. Brutsckin, P., Calvin, G.: Extracranial metastases from medulloblastomas. Radiology 107, 359-362 (1973) 3. Weiss, Z.: Metastasizing ependymoma of cauda equina. Cancer 8, 161-171 (1955) 4. Rubinstein, L.J.: Development of extracranial metastases from a malignant astrocytoma in the absence of previous craniotomy. Case report J. Neurosurg. 26, 542-547 (1967) 5. Lewis, M.B., Nuses, L.B., Powell, D.E., Sheriden, B.I.: Extra-axial spread of medulloblastoma. Cancer 31, 1287-1297 (1973) 6. Zimmerman, R.A., Bilaniuk, Z.T., Pahlajani, H.: Spectrum of medulloblastomas demonstrated by computed tomography. Radiology 126, 137-141 (1978) 7. Gado, M., Huete, I., Mickael, M.: Computerized tomography of intratentorial tumors. Semin. Roentgenol. 12, (1977)
E. Palacios et al.: Unusual Metastases from Medulloblastoma 8. Naidich, T.P., Lin, J.P., Leeds, N.E., Pudlowski, R.M., Naidich, J. B.: Primary tumors and other masses of the cerebellum and fourth ventricle differential diagnosis by computed tomography. Neuroradiology 14, 153-174 (1977) 9. Kazner, E., Aulich, A., Grumme, T.: Results of computerized axial tomography with infratentorial tumors. In: Cranial computerized tomography (eds. W. Lanksch, E. Kazner). pp. 90-103. New York: Springer 1976 10. Wilson, J. L., Moseley, I. F.: A diagnostic approach to cerebellar lesions. In: Computerized axial tomography in clinical practice (eds. G.H. du Boulay, I. F. Moseley), pp. 123-133. New York: Springer 1977 11. Gonzalez, C.F., Grossman, C.B., Palacios, E.: Computed brain and orbital tomography: technique and interpretation, pp. 129-134. New York: Wiley 1976 12. Enzman, D. R., Norman, D., Levin, V., Wilson, C., Newton, T. H.: Computed tomography in the follow-up of medulloblastomas and ependymomas. Radiology 128, 57-64 (1978) Received: 4 December 1978 Dr. E. Palacios Department of Radiology Loyola University Medical Center 2160 South First Avenue Maywood, IL 60153, USA
