A cta Neuroehirurgiea 32, 55---68 (1975) 9 by Springer-Verlag 1975
Department of Neurosurgery of the Spanish Social Security and the Faculty of Medicine of the Autonomous University, Madrid
Benign Cystic Tumours of the Cerebellum* By
S. 0brador and M. G. Blazquez With 9 Figures
Summary I n a series of 4.915 surgically treated intracranial tumours and other space-occupying lesions, excluding those due to trauma, the two main groups of benign cerebellar tumours were found to be the astrocytomas (172) and the cystic haemangioblastomas (35). Cerebellar astrocytomas represented 3.5% of all the brain tumour material and 8% of the total number of gliomas. The clinical features are reviewed, and the necessity for surgical and histological verification of the posterior fossa turnouts of childhood and youth is emphasized. Preoperative positive contrast ventrieulography was usually performed followed by temporal ventricular drainage or ventrieulo-peritoneal shunting. Cystic astroeytomas predominated. Radical removM of the solid part of these should be carried out. Total post-operative case mortality varied between 16 and 22~o b u t has become lower in recent years. Good late results varied between 40 and 70~o. Angioblastomas of the cerebellum are usually benign turnouts, with a cystic component in 700/o or more. Usually they represent the most important part of the so-called Lindau complex with possible associated angiomatosis of the retina (yon ttippel-Lindau disease) and, more rarely, visceral lesions or haemangioblastomas of the spinM cord. Cystic eerebellar angioblastomas represented 0.7~o of all brain tumours. The proportion of male patients was double that of females and the age toeak appeared between 30 and 40 years. An increase of red blood cells above five million per m m a appeared in 9o/0 of our cases. The value of vertebral angiography is emphasized. After emptying the cyst careful removal of the nodule gives a good late result in more t h a n 70~o of patients. However, recurrences have been noted in the literature in about 14~o of patients due to the frequency of multiple turnout nodules in the posterior fossa (10~o in some vertebral angiographie series). Finally, a most careful clinical and radiological search for other lesions in the rest of the body is imperative in these patients. * Paper presented at the Conference of the Hungarian Neurosurgieal Society, Siofok, September 1974.
56
S. Obrador and M. G. Blazquez:
This p a p e r deals w i t h 172 cerebellar a s t r o c y t o m a s a n d 35 cystic cerebcllar h a e m a n g i o b l a s t o m a s o u t of a t o t a l of 4.915 surgically t r e a t e d i n t r a e r a n i a l t u m o u r s a n d other space-occupying conditions, excluding t r a u m a t i c lesions, collected from 1946 to 1974. The d i s t r i b u t i o n of t h e different t y p e s of cerebellar t u m o u r s in our m a t e r i a l was as follows (Table 1): Table 1
Benigntumourseerebellar { Astroeytomas . . . . . . . . . . . . . . . . . . Cystic haemangioblastomas . . . . . . 863 Infratentoriallo- 7 calization (17%) \a
Choroid plexus papillomas of IV ventricle . . . . . . . . . . . . . . . . . . . . . .
Other rarer { Oligodendrogliomas . . . . . . . . . . . . tumours Teratomas . . . . . . . . . . . . . . . . . . . . Other cerebellar and IV ventricle tumours
( Medulloblastomas . . . . . . . . . . . . . .
i
Ependymoblastomas . . . . . . . . . . .
172 35 13 2 2 140 52
W e shall l i m i t our review to t h e two c o m m o n benign t u m o u r s of t h e cerebellum, t h e a s t r o e y t o m a s a n d t h e cystic h a e m a n g i o b l a s t o m a s .
Cerebellar Astrocytomas I n the course of his surgical career H a r v e y Cushing was able to s t u d y and operate on more t h a n 2,000 patients, an extraordinary number in those years (1900-1932). H e was also interested in finding the correlation between the clinical picture, post-operative evolution and histological features of all brain tumours. The gliomas formed t h e most frequent group (42~o in his series), and he asked Percival Bailey to study the various types of these tumours. The result of this collaboration was a classical book on the classification of gliomas, published in 1926 and dedicated to the Spanish School of Histology which had made fundamental studies of the different types of glia cells using specific staining methods. "l~ot all g]iomas are highly malignant, m a n y are slow growing and favourable for surgical removal" remarked H a r v e y Cushing. This sentence m a y be especially applied to astrocytoma of the cerebellum, an outstanding oxamp!e of benign tumour. T h e a s t r o c y t o m a s are f o r m e d b y v e r y m a t u r e a n d d i f f e r e n t i a t e d cells, longicellular a s t r o c y t o m a s of l~io-Hortega, which some a u t h o r s h a v e c o m p a r e d to t h e so-called s p o n g i o b l a s t o m a polare, an i n a p p r o p r i a t e a n d misleading n a m e (Russell a n d R u b i n s t e i n 1971). A c c o r d i n g to these a u t h o r s fine s t r u c t u r a l studies h a v e confirmed t h e i n t r a e e l l u l a r localization of R o s e n t h a l fibres a n d t h e i r r e l a t i o n s h i p to intense glial
Benign Cysgie Tumom's of the Cerebellum
57
filament-formation in the astroeytes. I n tissue culture the outgrowing cells are astroeytes. I n their series of 91 eases I~ussell and Rubinstein (1971) found wide variations in the microscopical appearances of this group and transitions from one histological pattern to another. Fibrillary and pilocytic astroeytes are found (slender hMr-like cells). The development of Rosenthal fibres is c o m m o n l y found in pilocytic areas. An interesting t h e o r y has been p u t forward by Scharenberg and Liss (1969) who consider the possible role t h a t m a y be played b y a peculiar t y p e of astroeytes only found in the molecular layer of the cerebellum (elements of Fafianas or feather cells). The relative benignity of eerebellar astroeytomas has been shown statistically. Grant (1956) mentioned t h a t out of a t h o u s a n d gliomas operated on in Philadelphia b y Frazier and his pupils only about 15% lived 5 or more years, but 70% of these were astroeytomas of the cerebellum. The 172 cerebellar astrocytomas in our series represent 3.5% of all our brain t u m o u r s and other intracranial space-occupying lesions, and 17% of those below the tentorium. I n relation to the total of our gliomas, astroeytomas of the cerebellum correspond to 8%. Elsewhere in the literature this figure varies from 8 to 16~o. The well k n o w n clinical features of these tumours in our material are summarized in Table 2: Table 2. Astrocytomas o/the Cerebdlum [ 63O/o below 15 years NO clear Length of !I 21% between sex preAge / 15 to 30 years clinical history dominance ] 15% between 31 to 50 years Symptoms
I Headaches and increase in i.e.p . . . . . 95O/o--> 90~o Initially i Cerebellar deficit . . . 5~o various ~0%
Less 1 year. . . . . 85% l t o 3 3 y e a r s . . . 8% 3 to 6 years . . . . 6%
Signs Papilloedema . . . . . . . . Nystagmus . . . . . . . . . . VI nerve palsy . . . . . . . VII nerve involvement Other cranial nerves..
96~o 40% 18~ 16~o 10%
Pyramidal and motor disturbances . . . . . . . 20~
Unilateral . . . . . . . . . . . Cerebellar deficit { Bilateral . . . . . . . . . . . . Midline . . . . . . . . . . . . .
58% 16~o 20%
58
S. Obrador and M. G. Blazquez:
I t is interesting from the differential diagnostic point of view t h a t the age peak for cerebellar astrocytomas is below 15 years of age with a curve similar to those of the two groups of more malignant tumours in this region, medulloblastomas and ependymomas. The high proportion of astrocytomas with a short history (85% less than one year) makes it very difficult to diagnose clinically the types of cerebellar and
Fig. 1. Iodoventriculography in eerebellar astroeytoma. Lateral view fourth ventricle tumours present in children. We believe the surgical and histological verification of every turnout of this region to be absolutely necessary. Before operation we usually perform positive contrast ventriculography (Figs. 1 and 2), after which we use continuous ventricular drainage for one to 3 days before proceeding further. In patients whose general condition is bad we perform a ventrieulo-peritoneal shunt and operate several days afterwards. Vertebral angiography has only been perfomned in some 0f our more recent cases. As Cushing remarked, most of these astroeytomas are cystic. Oliveerona (1967) found cystic tumours in two thirds of his 171 cases, as did Gol and MeKissoek (1959) in 86% of their 98. I n our experience the proportion of cystic astroeytomas was lower (60~o). In our cases localization in the eerebellar hemispheres was more frequent (63~o) than in the midline (37~o). The necessity of radical removal of all the nodular solid portion of
Benign. Cystic Tumours of the Cerebellum
59
the tumour has been well known since Cushing's days. Sometimes the solid part of the turnout is very large but with radical and careful surgery it m a y be totally removed. The total post-operative mortality rate of the large series reported in the literature, including our own, is between 16 and 220/o. Many of the earlier cases presented in an advanced state, but nowadays, with better
Fig. 2. Iodoventrieulography in astrocytoma of cerebellum.
A.P. view
diagnosis and the advances in anaesthesia and post-operative intensive care, the results are greatly improved. A late and troublesome complication in some patients is the development of a meningeal aseptic irritation that m a y lead to the formation of a cerebro-spinal fluid aecumulation over the area of eraniotomy in the posterior fossa. When repeated lumbar punctures fail to control this situation we have to resort to a ventrieulo-peritoneM shunt. Follow up of patients after removal of eerebellar astroeytomas shows that the great majority lead a useful life m a n y years after operation.
60
S. Obrador et al. : Benign Cystic Tumours of the Cerebellum
T h e percentages of these g o o d late results h a v e u s u a l l y v a r i e d b e t w e e n 57 a n d 78%, a n d we agree with 01iveerona who e s t i m a t e s t h a t 80 to 90~ of these p a t i e n t s should be cured. I n his series he o n l y f o u n d 8 e x a m p l e s (40/o) of m a l i g n a n t a s t r o e y t o m a s similar to those in t h e cerebral hemispheres w i t h a t e n d e n c y to recurrence. I n our m a t e r i a l our recurfence r a t e was 3~o. Russell a n d R u b i n s t e i n (1971) f o u n d definite cellular a n a p l a s i a in 10~o of t h e i r 91 examples. T a b l e 3 shows a c o m p a r i s o n of t h e different series in t h e l i t e r a t u r e : Table 3. Astrocytomas o/the Cerebellum Cushing (1931) (1932) N u m b e r of cases
76
GoI MeKissock Oliveerona Personal (1959) (1967) series
91
166
98
171
172
--
--
39%
44%
63%
Mostly
--
86%0
Two thirds
60%
20 %
22 %
20% Total removal 34% Partial
19 %
60%
78%
Location in cerebellar hemispheres - Cystic
Grant (1956)
Postoperative m o r t a l i t y rate
18 %
Good late result
57%
16 %
40%
65% (42% living normal life)
8 malignant Recurrences
--
(4%)
3%
Angioblastomas o~ the Cerebellum This interesting group of tmnours was first studied in the 1920 b y a young Swedish pathologist, Lindau (1926), and also b y Cushing and Bailey (1928). The latter considered t h e m to be true vascular tumours (angioblastomas) and not malformations. Other names have been used, such as haemangiomas, haemangioendotheliomas, angioretieulomas, haemangioblastomas, haemangioperitheliomas, etc. There are some with a hereditary component (as m a n y as 20% according to Archer et al. 1972). Other authors have considered them to be phakomatoses (Zfilch I956) or systemic maldevelopments, with associated lesions in other organs forming the socalled Lindau complex (Nibbelink et al. 1969, Russell and Rubinstein 1971). The f r e q u e n c y of t h e eerebellar a n g i o b l a s t o m a s has been e s t i m a t e d b e t w e e n 1 a n d 2 ~o in several series in t h e l i t e r a t u r e (Cushing a n d Bailey, Ziilch, Olivecrona, etc.). T h e p r e f e r e n t i a l l o c a t i o n of these t u m o u r s in
Fig. 3. Typical histological aspect of a cerebellar haemangioblastoma large vascular cavities and the peculiar foamy cells surrounding I-I. E. • 160 (Dr. J. Escalona)
with them,
Fig. 4, The dense re~ieulin framework around the vascular structures in a cerebellar haemangiohlastoma, IRetieulin staiI~ of iRio-I-[ortega X32 (Dr. J. Esoalona)
62
S. Obrador and M. G. Blazquez:
the cerebellum has been related to the development of the vascular network in the posterior fossa and especially to the remnants of the vascular plate in the dorsal medullary portion of the caudal end of the fourth ventricle. However, in the 70 cases operated on by Olivecrona (1952) 56 were located in the cerebellar hemispheres (80~o), 9 in the vermis and only 6 in the fourth ventricle. The mesodermal origin of these tumours formed by blood vessels and retieulin network has been recognized since the early studies of Lindau and Bailey (Figs. 3 and 4). The total number of posterior fossa haemangioblastomas in our series represents 1.3% of the total number of our brain turnouts and other intraeranial space-occupying lesions, but if we consider only the cystic lesions (35) the proportion is 0.7~0. In relation to all lesions in the posterior fossa the cystic haemangioblastomas represent 4%. In about 200 cases of these tumours collected from the literature, including our personal material, the proportion of solid tnmours with cystic formation was between 18 and 30%. A most interesting clinical feature of the eerebellar angioblastomas is their association with vascular lesions in the retina (yon Hippel-Lindau disease). This association is not frequent and is non-existent in the series of Olivecrona and ourselves, but it was found in 16 to 20% of eases in some centres. No doubt degrees of care in the study of the retina are responsible for some of these discrepancies. Even more rare and difficult to demonstrate is the presence of cystic lesions in the kidneys and other organs of the Lindau complex. The clinical findings of our cases are presented in the following Table 4 : Table 4. Angioblastomas o] the Cerebellum ( 30% below Twice as many | 21 years Length of] Less than 1 year 80% Sex,males as Age / 70% between !inieal to 10 years,. 20% [females ( 21 and 57 years ms~ory ( Symptoms
Initial {
Headaches, and increase in i.e.p . . . . . . . . . . . . . 74% ~+ 95%
Cerebellar deficit . . 10% -# 60%
Cerebelar
deficit
Signs :Papilloedema . . . . . . . . . Nystagmus . . . . . . . . . . . VI nerve palsy . . . . . . . . V I I nerve involvement
88% 42% 16% 11%
Pyramidal and motor disturbances . . . . . . . . 35% ............ Bilateral . . . . . . . . . . . . . {Unilateral Midline . . . . . . . . . . . . . .
36% 15 ~/o 10%
Benign Cystic Turnouts of the Cerebellum
63
As in other series the proportion of male patients was double that of females. The age peak appeared between 30 and 40 years. Apart from these two features of preponderance in males and appearanee at a later age than other eerebellar tumours the clinical differential diagnosis can only be definitely established when there is an associated retinal vascular abnormality or evidence of other visceral cystic lesions.
Fig. 5. Iodoventriculography in eerebellar angioblastoma. Lateral view
Another interesting feature of these angioblastomas is an increase in the total number of red blood cells. In our material 9% had a red cell count in excess of 5 million per mm 3 and in other series the figure was higher (10-20%) as reported by Iizuka (1969), although the figure from his own series was only 5~o. Djindjian (1963), in his series of 15 cerebellar angioreticulomas, found 26~o with a red cell count over 6 million per mm a. I-Ie emphasized differential diagnosis between angioblastoma and other posterior fossa tumours (espeeiMly hypernephroma metastases). Several theories have been advanced to explain this erythrocytosis. Some authors believe that these turnouts themselves pro-
64
S. Obrador and M. G. Blazquez:
duce erythropoietic substances but this hypothesis is not generally accepted. Air or positive contrast ventriculography was used in most of our earlier cases (Figs. 5 and 6). More recently vertebral angiography has demonstrated abnormal patterns with one or more vascular nodules (Figs. 7, 8, and 9). The importance of vertebral angiography for locali-
Fig. 6. A.P. view of a positive contrast ventrieulography in angiobtastoma of the cerebellum zation, estimation of size, demonstration of multiple lesions, and for planing operative technique has been emphasized by Papo et al. (1961), Pouyanne et al. (1962) and others. Most of the cystic angioblastomas arc in the cerebellar hemispheres (80~o of Olivecrona's cases and 88~ of our material). Total removal of the nodule is carried out after emptying the cyst. Sometimes the nodule
Benign Cystic Tumours of the Cerebellum
65
is very small. The total post-operative mortality was 19%, A good long term result was obtained in 73~o of the patients. Solid tumours carry a higher risk because of bleeding and the occasional involvement of the IV ventricle and brain stem. Recurrence of these tumours have been observed in 14 ~o [Oliveerona (1967) and Iizuka (1969)], I t is important to search for multiple nodules
Fig, 7. Lateral view of vertebral angiography in haemangioblastoma of cerebellum showing the typical nodule (Dr. V. G. Queimadelos)
in the eerebellar angioblastomas, and the value of vertebral angiography must once more be emphasized. [izuka (1969) considers that "recurrences" of Lindau's turnouts of the cerebellum are not true recurrences but are new lesions. In the review carried out by Djindjian (I963) it was reported that only about 50 eases of eerebellar angioblastoma had been studied by vertebral angiography since the first r e p o r t s from the Scandinavian School of Neuroradiology in the early fifties. I n spite of the world development of specialized neuroradiologieal services the eases reported in the literature are still few in number. The multiplicity of posterior fossa lesions in 10~o of the eases with associated angiomatosis retinae, adrenal, renal and pancreatic cysts has been emphasized by Archer et M. (1972). The association of haemangioblastomas of both spinal cord and, cerebellum has been noted by Di Chiro and Doppman (1969). Acta Neu.rochirurgica, gol, 32, Fasr 1--2
5
66
S. Obrador and M. G. Blazquez:
Fig. 8
Fig. 9 Figs. 8 and 9. Two other cases of cerebellar angioblastoma showing the filling of the nodule by vertebral angiogruphy at different stages (Dr. J. A. Silvela and Dr. J. F. Urdanibia)
Benign Cystic Tumours of the Cerebellum
67
Posterior fosse angioblastomas no d o u b t represent the most i m p o r t a n t part of the so-called Lindau complex but the elinieian should not forget angioblastie manifestations elsewhere, especially in the retinae, spinal cord, kidneys and other viscera. Some of these other lesions m a y be demonstrated n o w a d a y s b y special radiologieal techniques [Legr4 et el. (1968)]. I n a review of 19 eases of angioblastie t u m o u r s of the spinal cord, including a personal observation, Lepoire et M. (t969) found 10 eerebellar and 11 retinal lesions; visceral tumours were recorded in only 2 eases. A hereditary factor was present in 8 patients. Cystic angioblastomas of the cerebellmn are usually benign neurosurgical lesions but the possibility of multiple nodules in the posterior fossa in about 10 ~o of eases must by remembered. Vertebral angiography should be used routinely in the s t u d y of these tumours. I n addition, there m a y be other associated angioblastie and viseeral lesions which
may be asymptomatie. References
Archer, C.R., G . H . goberson, and J . M . Toreros, Posterior medullary hemangioblastoma. Radiology 103 (1972), 323--328. Bailey, P., and H. Cushing, A classiheation of tumors of the glioma group. Philadelphia: Lippincott. 1926. Cushing, I-I., Experiences with the cerebellar astroeytomas. Surg. Gynecol. Obstetr. 52 (1931), 129--204. -Intraeranial tumors. Springfield, Ill.: Ch. C Thomas. 1932. - - and P. Bailey, Tumors arising from blood vessels of the brain. Springfield, Ill. : Ch. C Thomas. 1928. Di Chiro, G., and J . L . Doppman, Differential angiographic features of hemangioblastomas and arteriovenous malformations of the spinal cord. Radiology 93 (1969), 25--30. Djindjian, R., A p r o p o s de 15 eas d'angioretieulomes du eervelet. Presse Med. 71 (1963), 1028--1030. Gel, A., and W. Mel{Jssoek, The eerebellar astroeytomas. A repor~ on 98 verified eases. J. l~Teurosurg. 16 (1959), 287--296. Grant, F. C., A study of the results of surgical treatment in 2,326 consecutive patients with brain tumor. J. Neurosurg. 13 (1956), 479--488. Iizuka, J., l~fickf/ille bei Lindautumoren. Aeta Neuroehir. 20 (1969), 281-298. Legr@, J., R. Sedan, J. Lavielle, J. P_ Clement et J. E. Paillas, Melodic de yon Hippel-Lindau. Ablation des angioretieulomes eerebelleux et guerison. Etude neuroradiologique avee exploration angiograph~que selective des loealisations viseerales. Neuro-Chirurgie 14 (1968), 583--597. Lepoire, J., P. Tridon, J'. Montaut, H. Hepner, L. Pieard et M. Weber, Angio-retieulome reeidivant au eours d'une maladie de yon HippelLindau. Aspects eliniques et anteriographiques. Neuro-Chirurgie 15 (1969), 529--534. Lindau, A., Studien fiber Kleinhirneyston. Bau, Pathogenese und Beziehungen zur Angiomatosis Retinue. Aeta Path. Mierobiol. Scand. Suppl. 1, 1926. 5~:~
68
S. Obrador et el. : Benign Cystic Tumours of the Cerebellum
Nibbelink, D. W., B. H. Peters, and W. F. McCormick, On the association of pheochromocytoma and cerebellar hemangioblastoma. Neurology 19 (1969), 455--460. Olivecrona, I-I., The cerebellar angioretieulomas. J. Neurosurg. 9 (1952), 317--330. - - The surgical treatment of intracranial tumors. I n H a n d b u c h dcr l~eurochirurgie edited by It. Olivecrona and W. TSnnis, Vol. 4. Berlin-Heidelberg-New York : Springer. 1967. Papo, I., F. Colombo, and A. Torizzi, Considerazione su 45 casi di angioreticuloma dell'eneephalo. Minerva Neurochir. 5 (1961), 92--100. Pouyanne, I-I., P. Leman, M. Got et M. Sall~s, Rdflexions sur six cas d'angior@tieulomes du cervelet et leur expression angiographique. I~eurochirurgie 8 (1962), 405--413. l~ussell, D. S., and L. J. l~ubinstein, Pathology of tumours of the nervous system. London: Arnold Publ. Ltd. 1971. Seharenberg, K., and L. Liss, Neuroectodermal tumors of the central and peripheral nervous system. Baltimore: Williams and Wilkins Co. 1969. Ziileh, K. J., Biologic und Pathologic der Hirngeschwiilste. In: Handbuch der Neurochirurgie, edited by H. Olivecrona and W. T6nnis, Vol. 3. Berlin-GSttingen-meidelberg: Springer. 1956. Authors' address: Prof. Dr. S. Obrador and Dr. M. G. Blazquez, Department of Neurosurgery of the Spanish Social Security and the Faculty of Medicine of the Autonomous University, Madrid, Spain.
Department of Neurosurgery of the Spanish Social Security and the Faculty of Medicine of the Autonomous University, Madrid
Benign Cystic Tumours of the Cerebellum* By
S. 0brador and M. G. Blazquez With 9 Figures
Summary I n a series of 4.915 surgically treated intracranial tumours and other space-occupying lesions, excluding those due to trauma, the two main groups of benign cerebellar tumours were found to be the astrocytomas (172) and the cystic haemangioblastomas (35). Cerebellar astrocytomas represented 3.5% of all the brain tumour material and 8% of the total number of gliomas. The clinical features are reviewed, and the necessity for surgical and histological verification of the posterior fossa turnouts of childhood and youth is emphasized. Preoperative positive contrast ventrieulography was usually performed followed by temporal ventricular drainage or ventrieulo-peritoneal shunting. Cystic astroeytomas predominated. Radical removM of the solid part of these should be carried out. Total post-operative case mortality varied between 16 and 22~o b u t has become lower in recent years. Good late results varied between 40 and 70~o. Angioblastomas of the cerebellum are usually benign turnouts, with a cystic component in 700/o or more. Usually they represent the most important part of the so-called Lindau complex with possible associated angiomatosis of the retina (yon ttippel-Lindau disease) and, more rarely, visceral lesions or haemangioblastomas of the spinM cord. Cystic eerebellar angioblastomas represented 0.7~o of all brain tumours. The proportion of male patients was double that of females and the age toeak appeared between 30 and 40 years. An increase of red blood cells above five million per m m a appeared in 9o/0 of our cases. The value of vertebral angiography is emphasized. After emptying the cyst careful removal of the nodule gives a good late result in more t h a n 70~o of patients. However, recurrences have been noted in the literature in about 14~o of patients due to the frequency of multiple turnout nodules in the posterior fossa (10~o in some vertebral angiographie series). Finally, a most careful clinical and radiological search for other lesions in the rest of the body is imperative in these patients. * Paper presented at the Conference of the Hungarian Neurosurgieal Society, Siofok, September 1974.
56
S. Obrador and M. G. Blazquez:
This p a p e r deals w i t h 172 cerebellar a s t r o c y t o m a s a n d 35 cystic cerebcllar h a e m a n g i o b l a s t o m a s o u t of a t o t a l of 4.915 surgically t r e a t e d i n t r a e r a n i a l t u m o u r s a n d other space-occupying conditions, excluding t r a u m a t i c lesions, collected from 1946 to 1974. The d i s t r i b u t i o n of t h e different t y p e s of cerebellar t u m o u r s in our m a t e r i a l was as follows (Table 1): Table 1
Benigntumourseerebellar { Astroeytomas . . . . . . . . . . . . . . . . . . Cystic haemangioblastomas . . . . . . 863 Infratentoriallo- 7 calization (17%) \a
Choroid plexus papillomas of IV ventricle . . . . . . . . . . . . . . . . . . . . . .
Other rarer { Oligodendrogliomas . . . . . . . . . . . . tumours Teratomas . . . . . . . . . . . . . . . . . . . . Other cerebellar and IV ventricle tumours
( Medulloblastomas . . . . . . . . . . . . . .
i
Ependymoblastomas . . . . . . . . . . .
172 35 13 2 2 140 52
W e shall l i m i t our review to t h e two c o m m o n benign t u m o u r s of t h e cerebellum, t h e a s t r o e y t o m a s a n d t h e cystic h a e m a n g i o b l a s t o m a s .
Cerebellar Astrocytomas I n the course of his surgical career H a r v e y Cushing was able to s t u d y and operate on more t h a n 2,000 patients, an extraordinary number in those years (1900-1932). H e was also interested in finding the correlation between the clinical picture, post-operative evolution and histological features of all brain tumours. The gliomas formed t h e most frequent group (42~o in his series), and he asked Percival Bailey to study the various types of these tumours. The result of this collaboration was a classical book on the classification of gliomas, published in 1926 and dedicated to the Spanish School of Histology which had made fundamental studies of the different types of glia cells using specific staining methods. "l~ot all g]iomas are highly malignant, m a n y are slow growing and favourable for surgical removal" remarked H a r v e y Cushing. This sentence m a y be especially applied to astrocytoma of the cerebellum, an outstanding oxamp!e of benign tumour. T h e a s t r o c y t o m a s are f o r m e d b y v e r y m a t u r e a n d d i f f e r e n t i a t e d cells, longicellular a s t r o c y t o m a s of l~io-Hortega, which some a u t h o r s h a v e c o m p a r e d to t h e so-called s p o n g i o b l a s t o m a polare, an i n a p p r o p r i a t e a n d misleading n a m e (Russell a n d R u b i n s t e i n 1971). A c c o r d i n g to these a u t h o r s fine s t r u c t u r a l studies h a v e confirmed t h e i n t r a e e l l u l a r localization of R o s e n t h a l fibres a n d t h e i r r e l a t i o n s h i p to intense glial
Benign Cysgie Tumom's of the Cerebellum
57
filament-formation in the astroeytes. I n tissue culture the outgrowing cells are astroeytes. I n their series of 91 eases I~ussell and Rubinstein (1971) found wide variations in the microscopical appearances of this group and transitions from one histological pattern to another. Fibrillary and pilocytic astroeytes are found (slender hMr-like cells). The development of Rosenthal fibres is c o m m o n l y found in pilocytic areas. An interesting t h e o r y has been p u t forward by Scharenberg and Liss (1969) who consider the possible role t h a t m a y be played b y a peculiar t y p e of astroeytes only found in the molecular layer of the cerebellum (elements of Fafianas or feather cells). The relative benignity of eerebellar astroeytomas has been shown statistically. Grant (1956) mentioned t h a t out of a t h o u s a n d gliomas operated on in Philadelphia b y Frazier and his pupils only about 15% lived 5 or more years, but 70% of these were astroeytomas of the cerebellum. The 172 cerebellar astrocytomas in our series represent 3.5% of all our brain t u m o u r s and other intracranial space-occupying lesions, and 17% of those below the tentorium. I n relation to the total of our gliomas, astroeytomas of the cerebellum correspond to 8%. Elsewhere in the literature this figure varies from 8 to 16~o. The well k n o w n clinical features of these tumours in our material are summarized in Table 2: Table 2. Astrocytomas o/the Cerebdlum [ 63O/o below 15 years NO clear Length of !I 21% between sex preAge / 15 to 30 years clinical history dominance ] 15% between 31 to 50 years Symptoms
I Headaches and increase in i.e.p . . . . . 95O/o--> 90~o Initially i Cerebellar deficit . . . 5~o various ~0%
Less 1 year. . . . . 85% l t o 3 3 y e a r s . . . 8% 3 to 6 years . . . . 6%
Signs Papilloedema . . . . . . . . Nystagmus . . . . . . . . . . VI nerve palsy . . . . . . . VII nerve involvement Other cranial nerves..
96~o 40% 18~ 16~o 10%
Pyramidal and motor disturbances . . . . . . . 20~
Unilateral . . . . . . . . . . . Cerebellar deficit { Bilateral . . . . . . . . . . . . Midline . . . . . . . . . . . . .
58% 16~o 20%
58
S. Obrador and M. G. Blazquez:
I t is interesting from the differential diagnostic point of view t h a t the age peak for cerebellar astrocytomas is below 15 years of age with a curve similar to those of the two groups of more malignant tumours in this region, medulloblastomas and ependymomas. The high proportion of astrocytomas with a short history (85% less than one year) makes it very difficult to diagnose clinically the types of cerebellar and
Fig. 1. Iodoventriculography in eerebellar astroeytoma. Lateral view fourth ventricle tumours present in children. We believe the surgical and histological verification of every turnout of this region to be absolutely necessary. Before operation we usually perform positive contrast ventriculography (Figs. 1 and 2), after which we use continuous ventricular drainage for one to 3 days before proceeding further. In patients whose general condition is bad we perform a ventrieulo-peritoneal shunt and operate several days afterwards. Vertebral angiography has only been perfomned in some 0f our more recent cases. As Cushing remarked, most of these astroeytomas are cystic. Oliveerona (1967) found cystic tumours in two thirds of his 171 cases, as did Gol and MeKissoek (1959) in 86% of their 98. I n our experience the proportion of cystic astroeytomas was lower (60~o). In our cases localization in the eerebellar hemispheres was more frequent (63~o) than in the midline (37~o). The necessity of radical removal of all the nodular solid portion of
Benign. Cystic Tumours of the Cerebellum
59
the tumour has been well known since Cushing's days. Sometimes the solid part of the turnout is very large but with radical and careful surgery it m a y be totally removed. The total post-operative mortality rate of the large series reported in the literature, including our own, is between 16 and 220/o. Many of the earlier cases presented in an advanced state, but nowadays, with better
Fig. 2. Iodoventrieulography in astrocytoma of cerebellum.
A.P. view
diagnosis and the advances in anaesthesia and post-operative intensive care, the results are greatly improved. A late and troublesome complication in some patients is the development of a meningeal aseptic irritation that m a y lead to the formation of a cerebro-spinal fluid aecumulation over the area of eraniotomy in the posterior fossa. When repeated lumbar punctures fail to control this situation we have to resort to a ventrieulo-peritoneM shunt. Follow up of patients after removal of eerebellar astroeytomas shows that the great majority lead a useful life m a n y years after operation.
60
S. Obrador et al. : Benign Cystic Tumours of the Cerebellum
T h e percentages of these g o o d late results h a v e u s u a l l y v a r i e d b e t w e e n 57 a n d 78%, a n d we agree with 01iveerona who e s t i m a t e s t h a t 80 to 90~ of these p a t i e n t s should be cured. I n his series he o n l y f o u n d 8 e x a m p l e s (40/o) of m a l i g n a n t a s t r o e y t o m a s similar to those in t h e cerebral hemispheres w i t h a t e n d e n c y to recurrence. I n our m a t e r i a l our recurfence r a t e was 3~o. Russell a n d R u b i n s t e i n (1971) f o u n d definite cellular a n a p l a s i a in 10~o of t h e i r 91 examples. T a b l e 3 shows a c o m p a r i s o n of t h e different series in t h e l i t e r a t u r e : Table 3. Astrocytomas o/the Cerebellum Cushing (1931) (1932) N u m b e r of cases
76
GoI MeKissock Oliveerona Personal (1959) (1967) series
91
166
98
171
172
--
--
39%
44%
63%
Mostly
--
86%0
Two thirds
60%
20 %
22 %
20% Total removal 34% Partial
19 %
60%
78%
Location in cerebellar hemispheres - Cystic
Grant (1956)
Postoperative m o r t a l i t y rate
18 %
Good late result
57%
16 %
40%
65% (42% living normal life)
8 malignant Recurrences
--
(4%)
3%
Angioblastomas o~ the Cerebellum This interesting group of tmnours was first studied in the 1920 b y a young Swedish pathologist, Lindau (1926), and also b y Cushing and Bailey (1928). The latter considered t h e m to be true vascular tumours (angioblastomas) and not malformations. Other names have been used, such as haemangiomas, haemangioendotheliomas, angioretieulomas, haemangioblastomas, haemangioperitheliomas, etc. There are some with a hereditary component (as m a n y as 20% according to Archer et al. 1972). Other authors have considered them to be phakomatoses (Zfilch I956) or systemic maldevelopments, with associated lesions in other organs forming the socalled Lindau complex (Nibbelink et al. 1969, Russell and Rubinstein 1971). The f r e q u e n c y of t h e eerebellar a n g i o b l a s t o m a s has been e s t i m a t e d b e t w e e n 1 a n d 2 ~o in several series in t h e l i t e r a t u r e (Cushing a n d Bailey, Ziilch, Olivecrona, etc.). T h e p r e f e r e n t i a l l o c a t i o n of these t u m o u r s in
Fig. 3. Typical histological aspect of a cerebellar haemangioblastoma large vascular cavities and the peculiar foamy cells surrounding I-I. E. • 160 (Dr. J. Escalona)
with them,
Fig. 4, The dense re~ieulin framework around the vascular structures in a cerebellar haemangiohlastoma, IRetieulin staiI~ of iRio-I-[ortega X32 (Dr. J. Esoalona)
62
S. Obrador and M. G. Blazquez:
the cerebellum has been related to the development of the vascular network in the posterior fossa and especially to the remnants of the vascular plate in the dorsal medullary portion of the caudal end of the fourth ventricle. However, in the 70 cases operated on by Olivecrona (1952) 56 were located in the cerebellar hemispheres (80~o), 9 in the vermis and only 6 in the fourth ventricle. The mesodermal origin of these tumours formed by blood vessels and retieulin network has been recognized since the early studies of Lindau and Bailey (Figs. 3 and 4). The total number of posterior fossa haemangioblastomas in our series represents 1.3% of the total number of our brain turnouts and other intraeranial space-occupying lesions, but if we consider only the cystic lesions (35) the proportion is 0.7~0. In relation to all lesions in the posterior fossa the cystic haemangioblastomas represent 4%. In about 200 cases of these tumours collected from the literature, including our personal material, the proportion of solid tnmours with cystic formation was between 18 and 30%. A most interesting clinical feature of the eerebellar angioblastomas is their association with vascular lesions in the retina (yon Hippel-Lindau disease). This association is not frequent and is non-existent in the series of Olivecrona and ourselves, but it was found in 16 to 20% of eases in some centres. No doubt degrees of care in the study of the retina are responsible for some of these discrepancies. Even more rare and difficult to demonstrate is the presence of cystic lesions in the kidneys and other organs of the Lindau complex. The clinical findings of our cases are presented in the following Table 4 : Table 4. Angioblastomas o] the Cerebellum ( 30% below Twice as many | 21 years Length of] Less than 1 year 80% Sex,males as Age / 70% between !inieal to 10 years,. 20% [females ( 21 and 57 years ms~ory ( Symptoms
Initial {
Headaches, and increase in i.e.p . . . . . . . . . . . . . 74% ~+ 95%
Cerebellar deficit . . 10% -# 60%
Cerebelar
deficit
Signs :Papilloedema . . . . . . . . . Nystagmus . . . . . . . . . . . VI nerve palsy . . . . . . . . V I I nerve involvement
88% 42% 16% 11%
Pyramidal and motor disturbances . . . . . . . . 35% ............ Bilateral . . . . . . . . . . . . . {Unilateral Midline . . . . . . . . . . . . . .
36% 15 ~/o 10%
Benign Cystic Turnouts of the Cerebellum
63
As in other series the proportion of male patients was double that of females. The age peak appeared between 30 and 40 years. Apart from these two features of preponderance in males and appearanee at a later age than other eerebellar tumours the clinical differential diagnosis can only be definitely established when there is an associated retinal vascular abnormality or evidence of other visceral cystic lesions.
Fig. 5. Iodoventriculography in eerebellar angioblastoma. Lateral view
Another interesting feature of these angioblastomas is an increase in the total number of red blood cells. In our material 9% had a red cell count in excess of 5 million per mm 3 and in other series the figure was higher (10-20%) as reported by Iizuka (1969), although the figure from his own series was only 5~o. Djindjian (1963), in his series of 15 cerebellar angioreticulomas, found 26~o with a red cell count over 6 million per mm a. I-Ie emphasized differential diagnosis between angioblastoma and other posterior fossa tumours (espeeiMly hypernephroma metastases). Several theories have been advanced to explain this erythrocytosis. Some authors believe that these turnouts themselves pro-
64
S. Obrador and M. G. Blazquez:
duce erythropoietic substances but this hypothesis is not generally accepted. Air or positive contrast ventriculography was used in most of our earlier cases (Figs. 5 and 6). More recently vertebral angiography has demonstrated abnormal patterns with one or more vascular nodules (Figs. 7, 8, and 9). The importance of vertebral angiography for locali-
Fig. 6. A.P. view of a positive contrast ventrieulography in angiobtastoma of the cerebellum zation, estimation of size, demonstration of multiple lesions, and for planing operative technique has been emphasized by Papo et al. (1961), Pouyanne et al. (1962) and others. Most of the cystic angioblastomas arc in the cerebellar hemispheres (80~o of Olivecrona's cases and 88~ of our material). Total removal of the nodule is carried out after emptying the cyst. Sometimes the nodule
Benign Cystic Tumours of the Cerebellum
65
is very small. The total post-operative mortality was 19%, A good long term result was obtained in 73~o of the patients. Solid tumours carry a higher risk because of bleeding and the occasional involvement of the IV ventricle and brain stem. Recurrence of these tumours have been observed in 14 ~o [Oliveerona (1967) and Iizuka (1969)], I t is important to search for multiple nodules
Fig, 7. Lateral view of vertebral angiography in haemangioblastoma of cerebellum showing the typical nodule (Dr. V. G. Queimadelos)
in the eerebellar angioblastomas, and the value of vertebral angiography must once more be emphasized. [izuka (1969) considers that "recurrences" of Lindau's turnouts of the cerebellum are not true recurrences but are new lesions. In the review carried out by Djindjian (I963) it was reported that only about 50 eases of eerebellar angioblastoma had been studied by vertebral angiography since the first r e p o r t s from the Scandinavian School of Neuroradiology in the early fifties. I n spite of the world development of specialized neuroradiologieal services the eases reported in the literature are still few in number. The multiplicity of posterior fossa lesions in 10~o of the eases with associated angiomatosis retinae, adrenal, renal and pancreatic cysts has been emphasized by Archer et M. (1972). The association of haemangioblastomas of both spinal cord and, cerebellum has been noted by Di Chiro and Doppman (1969). Acta Neu.rochirurgica, gol, 32, Fasr 1--2
5
66
S. Obrador and M. G. Blazquez:
Fig. 8
Fig. 9 Figs. 8 and 9. Two other cases of cerebellar angioblastoma showing the filling of the nodule by vertebral angiogruphy at different stages (Dr. J. A. Silvela and Dr. J. F. Urdanibia)
Benign Cystic Tumours of the Cerebellum
67
Posterior fosse angioblastomas no d o u b t represent the most i m p o r t a n t part of the so-called Lindau complex but the elinieian should not forget angioblastie manifestations elsewhere, especially in the retinae, spinal cord, kidneys and other viscera. Some of these other lesions m a y be demonstrated n o w a d a y s b y special radiologieal techniques [Legr4 et el. (1968)]. I n a review of 19 eases of angioblastie t u m o u r s of the spinal cord, including a personal observation, Lepoire et M. (t969) found 10 eerebellar and 11 retinal lesions; visceral tumours were recorded in only 2 eases. A hereditary factor was present in 8 patients. Cystic angioblastomas of the cerebellmn are usually benign neurosurgical lesions but the possibility of multiple nodules in the posterior fossa in about 10 ~o of eases must by remembered. Vertebral angiography should be used routinely in the s t u d y of these tumours. I n addition, there m a y be other associated angioblastie and viseeral lesions which
may be asymptomatie. References
Archer, C.R., G . H . goberson, and J . M . Toreros, Posterior medullary hemangioblastoma. Radiology 103 (1972), 323--328. Bailey, P., and H. Cushing, A classiheation of tumors of the glioma group. Philadelphia: Lippincott. 1926. Cushing, I-I., Experiences with the cerebellar astroeytomas. Surg. Gynecol. Obstetr. 52 (1931), 129--204. -Intraeranial tumors. Springfield, Ill.: Ch. C Thomas. 1932. - - and P. Bailey, Tumors arising from blood vessels of the brain. Springfield, Ill. : Ch. C Thomas. 1928. Di Chiro, G., and J . L . Doppman, Differential angiographic features of hemangioblastomas and arteriovenous malformations of the spinal cord. Radiology 93 (1969), 25--30. Djindjian, R., A p r o p o s de 15 eas d'angioretieulomes du eervelet. Presse Med. 71 (1963), 1028--1030. Gel, A., and W. Mel{Jssoek, The eerebellar astroeytomas. A repor~ on 98 verified eases. J. l~Teurosurg. 16 (1959), 287--296. Grant, F. C., A study of the results of surgical treatment in 2,326 consecutive patients with brain tumor. J. Neurosurg. 13 (1956), 479--488. Iizuka, J., l~fickf/ille bei Lindautumoren. Aeta Neuroehir. 20 (1969), 281-298. Legr@, J., R. Sedan, J. Lavielle, J. P_ Clement et J. E. Paillas, Melodic de yon Hippel-Lindau. Ablation des angioretieulomes eerebelleux et guerison. Etude neuroradiologique avee exploration angiograph~que selective des loealisations viseerales. Neuro-Chirurgie 14 (1968), 583--597. Lepoire, J., P. Tridon, J'. Montaut, H. Hepner, L. Pieard et M. Weber, Angio-retieulome reeidivant au eours d'une maladie de yon HippelLindau. Aspects eliniques et anteriographiques. Neuro-Chirurgie 15 (1969), 529--534. Lindau, A., Studien fiber Kleinhirneyston. Bau, Pathogenese und Beziehungen zur Angiomatosis Retinue. Aeta Path. Mierobiol. Scand. Suppl. 1, 1926. 5~:~
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S. Obrador et el. : Benign Cystic Tumours of the Cerebellum
Nibbelink, D. W., B. H. Peters, and W. F. McCormick, On the association of pheochromocytoma and cerebellar hemangioblastoma. Neurology 19 (1969), 455--460. Olivecrona, I-I., The cerebellar angioretieulomas. J. Neurosurg. 9 (1952), 317--330. - - The surgical treatment of intracranial tumors. I n H a n d b u c h dcr l~eurochirurgie edited by It. Olivecrona and W. TSnnis, Vol. 4. Berlin-Heidelberg-New York : Springer. 1967. Papo, I., F. Colombo, and A. Torizzi, Considerazione su 45 casi di angioreticuloma dell'eneephalo. Minerva Neurochir. 5 (1961), 92--100. Pouyanne, I-I., P. Leman, M. Got et M. Sall~s, Rdflexions sur six cas d'angior@tieulomes du cervelet et leur expression angiographique. I~eurochirurgie 8 (1962), 405--413. l~ussell, D. S., and L. J. l~ubinstein, Pathology of tumours of the nervous system. London: Arnold Publ. Ltd. 1971. Seharenberg, K., and L. Liss, Neuroectodermal tumors of the central and peripheral nervous system. Baltimore: Williams and Wilkins Co. 1969. Ziileh, K. J., Biologic und Pathologic der Hirngeschwiilste. In: Handbuch der Neurochirurgie, edited by H. Olivecrona and W. T6nnis, Vol. 3. Berlin-GSttingen-meidelberg: Springer. 1956. Authors' address: Prof. Dr. S. Obrador and Dr. M. G. Blazquez, Department of Neurosurgery of the Spanish Social Security and the Faculty of Medicine of the Autonomous University, Madrid, Spain.
