Neurocytoma Accompanied by Intraventricular Hemorrhage: Case Report and Literature Review Wendy R. K. Smoker,1 Jeannette J. Townsend,2 and Mark V. Reichman3

765

Neurocytomas are a rare subset of primary cerebral neu­roblastomas. They occur within the ventricles of young adults, may calcify , and demonstrate a better prognosis than do their parenchymal counterparts . Of the 21 patients reported in the

literature who appear to meet most of the criteria for th is diagnosis, 18 had symptoms referable to increased intracra­nial pressure [1-1 0]. The lesions were discovered incidentally in the other three patients [5, 7]. The patient who is the

Fig. 1.-A, Unenhanced CT scan at time of admission reveals intraventricular hemorrhage and acute hydrocephalus.

B, Left internal carotid artery angiogram, an­teroposterior view, shows slight enlargement of a lenticulostriate artery (small arrowheads), early opacification of thalamostriate vein (arrows), and avascular mass effect bowing other lentic­ulostriate vessels laterally (large arrowheads).

C and D, Sagittal (C) and axial (D) T1-weighted MR images (600/ 20/ 1) obtained 5 days after presentation. High signal intensity within left lateral ventricle is compatible with subacute hemorrhage. Flow void from early draining left thalamostriate vein is quite prominent (arrow­heads).

A

c

B

D

Received August 16, 1990; returned for revision September 27, 1990; revision received January 7, 1991 ; accepted January 9, 1991 . Presented at the annual meeting of the American Society of Neuroradiology, Los Angeles, CA. March 1990. 'Department of Radiology, University of Utah, Salt Lake City, UT 84132. Present address: Department of Radiology, Medical College of Virginia , MCV Station ,

Box 615, Richmond, VA 23298. Address reprint requests toW. R. K. Smoker. 2 Department of Pathology, University of Utah, Salt Lake City, UT 84132. 3 Department of Neurosurgery, University of Utah , Salt Lake City, UT 84132 .

AJNR 12:765-770, July/August 1991 0195-6108/91/1204-0765 © American Society of Neuroradiology

766 SMOKER ET AL. AJNR:12, July/August 1991

A B

D

F G

subject of this report presented with intraventricular hemor­rhage.

Case Report

A previously healthy 26-year-old man was seen at an outside emergency department following a single grand mal seizure. His

c

Fig. 2.-A, Unenhanced CT scan 4 months after initial ictus reveals a heterogeneous hyper­dense lesion in left lateral ventricle (M) and left lateral ventricular obstruction.

8 and C, Sagittal (8) and axial (C) T1-weighted MR images obtained 5 months after admission reveal a heterogeneous mass (M), isointense relative to cortex. Flow void from left thalamostriate vein is less prominent than on previous MR study (arrowhead) .

D and E, Proton density- (D) and T2- (E) weighted axial images (2800/30-60/0.75) reveal lesion to be generally hyperintense relative to cortex, with hypointense areas due to hemosid­erin deposition, most appreciable on T2 weighted image.

F and G, Coronal (F) and axial (G) T1-weighted images obtained after administration of gadopentetate dimeglumine show enhance­ment of lesion and better define its left lateral ventricular location.

Glasgow coma scale score was 7. Unenhanced CT demonstrated a large intraventricular hemorrhage with acute obstructive hydroceph­alus and subarachnoid hemorrhage (Fig . 1 A). After transfer to our institution and bilateral ventriculostomies , cerebral angiography was performed, which demonstrated a small smooth aneurysm in the distal right vertebral artery, prominence of a left lenticulostriate artery , and early opacification of the left thalamostriate vein (Fig. 1 B). There

AJNR :12, July/August 1991 NEUROCYTOMA WITH INTRAVENTRICULAR HEMORRHAGE 767

Fig. 3.-Light microscopic section reveals small, round, uniform nuclei within fibrillary background. Well-formed ring of nuclei is seen surrounding acellular fibrillary center. Wright rosette (arrowheads}. (H and E, original magnification x750)

was no angiographic evidence of neovascularity or late venous tumor blush. T1 -weighted MR imaging, 600/20/1 (TRfTEfexcitations), per­formed 5 days after the seizure , demonstrated intraventricular hem­orrhage and provided no additional information (Figs. 1 C and 1 D) . The diagnosis following these studies was a partially thrombosed intraventricular arteriovenous malformation.

Over the next 3 months the patient slowly made a complete neurologic recovery with the exception of a mild deficit in short-term memory. Serial follow-up unenhanced CT scans demonstrated pro­gressive resolution of the intraventricular hemorrhage and suggested a left lateral ventricular mass (Fig. 2A). Angiography no longer dem­onstrated the prominent left lenticulostriate artery or the early draining thalamostriate vein. There was no change in the size or configuration of the vertebral artery aneurysm.

An MR study 5 months after initial presentation revealed a mass within the body of the left lateral ventricle (Figs. 2B-2G). The lesion was slightly heterogeneous and isointense relative to the cortex on the T1 -weighted study and slightly hyperintense on the intermediate­and T2-weighted images. Tumor enhancement was seen after the administration of gadopentetate dimeglumine (Figs. 2F and 2G).

The patient underwent transcallosal biopsy and resection of the tumor. Light microscopic examination demonstrated small , round , symmetric nuclei forming multiple Wright rosettes (Fig. 3). Hemosid­erin was present, but there was no calcification and mitoses were absent . Ultrastructural studies revealed numerous cell processes with neurofilaments and neurotubules, occasional dense core granules, and synaptic vesicles. Although well-formed junctional synapses were not present, the diagnosis of neurocytoma was believed to be appro­priate because of the benign appearance of the cells.

Discussion

The terms neurocytoma, intracranial neuroblastoma, and differentiated neuroblastoma have been a source of confusion in recent literature. In 1982, Hassoun et al. [1] described two men who had calcified intraventricular tumors composed of small regular cells with clear cytoplasm that were grouped in

clusters in a fibrillary stroma. Striking neuronal differentiation with numerous synapses was present on electron micro­scopic examination, and the term central neurocytoma was applied to these unusual tumors [1J. We were able to find only three other cases in the literature that satisfied both the light and electron microscopic criteria of neurocytoma (pres­ence of synapses) as defined by Hassoun; those cases were reported by Townsend and Seaman [5], Poon et al. [6J , and Bolen et al. [9J. Nishio et al. [7J reported six cases designated as neurocytoma and Patil et al. [1 OJ reported one, even though well-formed synapses were not present on electron micros­copy in any of these patients. Patil et al. described a second case of neurocytoma in which ultrastructural verification of synapses was not possible because electron microscopy was not performed. To add to the nosologic confusion , Jerdan et al. [2J reported two cases pathologically similar to those described by Hassoun et al. , but , because they lacked syn­apses , they were termed differentiated neuroblastomas. Wil­son et al. [4] reported a similar lesion under the same name in 1985. Ferreol et al. [8J discussed both parenchymal neu­roblastomas and intraventricular neurocytomas in their re­view. The tumor in their case, designated as a neuroblastoma/ neurocytoma, lacked synapses but was similar in other re­spects to the other neurocytomas reported . The three cases reported by Pearl et al . [3J , under the heading primary cerebral neuroblastoma, were tumors with characteristics similar to those reported as neurocytomas by other authors.

It would appear from our review (see Table 1) that neuro­cytomas are primarily tumors of the lateral and third ventricles in patients over the age of 15 who have symptoms of in­creased intracranial pressure. These lesions may or may not be calcified . Of the 18 patients listed in Table 1 in whom CT was performed, calcification was demonstrated in 10. Angie­graphically, these lesions may be vascular or avascular in nature. On light microscopic examination, neurocytomas are composed of mature , small , regular, round neuronal cells with scant cytoplasm, not mature ganglion cells. Ultrastructural examination has revealed the absence of definite synapses in most of the reported cases. Follow-up studies in the majority of these cases have confirmed the benign nature of these tumors , whether or not synapses were present ultrastruc­turally . We agree with Nishio et al. [7J that these tumors with small , regular, benign-appearing cells should be termed neu­rocytomas, whether or not synapses are found in the ultra­structure.

Only three tumors reported before our present case were studied by MR imaging [9, 1 OJ . Two were isointense relative to cortex on T1-, proton density-, and T2-weighted imaging while the third demonstrated slight hyperintensity on the proton density- and T2-weighted images. Two demonstrated large vascular flow voids. In our patient, who had an intraven­tricular hemorrhage, hyperintensity, as well as areas of prom­inent hypointensity due to the presence of hemosiderin , were seen on proton density- and T2-weighted images obtained 5 months after the ictus. Mild enhancement was seen after administration of gadopentetate dimeglumine.

The most impressive characteristic of these rare lesions is their benign biological activity. A review of the follow-up

TA

BL

E 1

: D

emo

gra

ph

ic a

nd

Im

agin

g F

eatu

res

of

Neu

rocy

tom

as R

epo

rted

in

the

Lit

erat

ure

Refere~=~eT~:

Use

d/

~j,.~

Sex

S

ymp

tom

s at

P

rese

ntat

ion

Lo

catio

n

CT

Fin

ding

s A

ngio

grap

hic

Fin

ding

s M

R F

indi

ngs

Has

soun

et

al.

11 L

19

82

: ce

ntra

l n

eu

rocy

tom

a

1 32

2 39

Jerd

an e

t al

. [2

), 1

98

3:

diff

eren

tiate

d ce

re-

bral

ne

uro

bla

sto

ma

3 4

Pea

rl et

al.

13],

19

85

: pr

i-m

ary

cere

bral

neu

ro-

blas

tom

a 5 6 7

Wils

on e

t a

l.[4

), 1

98

5:

diff

eren

tiate

d ce

re­

bral

ne

uro

bla

sto

ma

8

To

wn

sen

d a

nd S

eam

an

[5],

198

6: c

entr

al

ne

uro

cyto

ma

9 10

23

48

23

52

19

25

25

42

M

Pro

gres

sive

me

mo

ry lo

ss,

Late

ral

and

third

Hug

e ca

lcifi

ed m

ass

; N

ot p

erfo

rmed

No

t pe

rfor

med

la

ck o

f in

itiat

ive

, dis

-ve

ntri

cles

no

enh

ance

men

t o

rie

nta

tion

M

P

rogr

essi

ve m

em

ory

loss

, La

tera

l an

d th

ird H

uge

calc

ified

mas

s;

No

t pe

rfor

med

Not

per

form

ed

incr

ease

d IC

P

vent

ricl

es

no m

entio

n o

f en

­ha

ncem

ent

M

Incr

ease

d IC

P

M

Incr

ease

d IC

P

M

Incr

ease

d IC

P

F

Incr

ease

d IC

P

M

Incr

ease

d IC

P

M

Incr

ease

d IC

P

F

F

His

tory

of

head

ache

(d

ead

on a

rriv

al)

Dru

g o

verd

ose

Late

ral

vent

ricl

e N

o m

entio

n o

f ca

lci-

Not

per

form

ed N

ot

perf

orm

ed

ficat

ion

or

en-

hanc

emen

t La

tera

l ve

ntric

le

No

men

tion

of

calc

i-N

ot

perf

orm

ed N

ot

perf

orm

ed

ficat

ion

or

en-

hanc

emen

t

Late

ral

vent

ricle

N

o m

entio

n of

cal

ci-

Not

per

form

ed N

ot p

erfo

rmed

fic

atio

n o

r en

-ha

nce

men

t La

tera

l ve

ntric

le

Cal

cifie

d m

ass

; co

n­tr

ast

enh

ance

­m

ent

Late

ral

ven

tric

le

Ca

lcifi

ed m

ass;

con

­tr

ast

enh

ance

­m

en

t

Lat

eral

and

thi

rd N

o c

alci

ficat

ion

; no

vent

ricl

es

men

tion

of e

n­h

an

cem

en

t

Late

ral

and

thir

d N

ot

perf

orm

ed

vent

ricl

es

Late

ral

vent

ricl

e C

alci

ficat

ion

and

con

tra

st e

nhan

ce­

me

nt

Litt

le v

ascu

lar-

Not

per

form

ed

ity;

blus

h in

to v

enou

s ph

ase;

en-

larg

ed p

os-

tero

late

ral,

po

ste

rom

e-

dial

, and

an-

teri

or c

ho-

roid

al a

rter

-ie

s N

o ne

ovas

cu­

lari

ty, e

n­la

rged

ves

-se

ls, o

r tu

-m

or

stai

n

No

t pe

rfor

med

"Lar

ge m

idlin

e N

ot p

erfo

rmed

va

scu

lar

tu-

mo

r fil

ling

bo

th l

ater

al

vent

ric

les

"

Not

per

form

ed N

ot

perf

orm

ed

Pos

teri

or c

ho

-N

ot p

erfo

rmed

ro

idal

art

ery

su

pp

lyin

g

Pat

holo

gic

Fin

ding

s T

rea

tme

nt

Fol

low

-up

and

Out

com

e

Str

ikin

g ne

uron

al d

iffer

-T

otal

res

ectio

n;

radi

atio

n D

ied

from

men

ingi

tis

entia

tion;

num

erou

s th

erap

y (b

rain

and

at

4 m

on

ths;

no

syna

pses

co

rd)

tum

or

pres

ent

Str

ikin

g ne

uron

al d

iffer

-T

otal

res

ectio

n A

live

at 2

4 m

onth

s;

entia

tion

; nu

mer

ous

no r

ecur

renc

e sy

naps

es

Den

se c

ore

gra

nule

s;

Bio

psy

only

; tr

ea

tme

nt

Fol

low

-up

no

t re

-n

o w

ell-

form

ed s

yn-

no

t de

scri

bed

port

ed

apse

s D

ense

cor

e gr

anul

es;

Bio

psy

only

; tre

atm

en

t F

ollo

w-u

p n

ot

re-

no w

ell-

form

ed s

yn-

no

t de

scri

bed

port

ed

apse

s

No

defin

ite s

ynap

ses

Su

bto

tal

rese

ctio

n; r

a-A

live

at 4

1 12 y

ears

; di

atio

n th

erap

y (w

ho

le

no r

ecur

renc

e br

ain)

N

o d

efin

ite s

ynap

ses

Bio

psy

; rad

iatio

n th

erap

y A

live

at 6

mo

nth

s;

No

defin

ite s

ynap

ses

(who

le b

rain

) no

tu

mo

r g

row

th

bu

t tu

mo

r ce

lls in

C

SF

Bio

psy;

rad

iatio

n th

erap

y A

live;

fol

low

-up

in-

(who

le b

rain

) te

rval

no

t re

­po

rted

No

junc

tiona

l sy

naps

es "

Deb

ulki

ng"

Die

d po

stop

erat

ivel

y fr

om b

leed

ing

LM: s

ma

ll, r

ound

nu­

clei

, W

rig

ht

rose

ttes

, no

mito

ses;

EM

: un

­su

cces

sful

W

ell-d

efin

ed s

ynap

ses

with

ju

nct

ion

s

No

t ap

plic

able

Tot

al r

esec

tion

Dea

d on

arr

ival

Aliv

e at

12

mon

ths;

no

rec

urre

nce

--.J

0>

(X

)

(J) s: 0 A m

JJ

m

-i

)>

! )>

'­ z :Il -"' '­ c: ~

)>

c:

<0

c:

~

<D

<D

Poo

n et

al.

[6],

198

8: p

ri­m

ary

cere

bral

neu

ro­

bla

stom

a

mas

s; n

o ev

iden

ce o

f in

crea

sed

vasc

ular

ity

11

17

F

Incr

ease

d IC

P

Th

ird v

entr

icle

C

alc

ifica

tion

and

Not

per

form

ed

No

t pe

rfor

med

S

ynap

tic c

om

ple

xes

with

we

ll-fo

rmed

ju

nctio

ns s

een

thro

ug

ho

ut

Nis

hio

et a

l. [7

], 1

988

: ce

ntra

l ne

uroc

yte-

ma

• 12

13

14

15

16

17

Fer

reol

et

al.

[8],

198

9:

cere

bral

neu

ro­

blas

tom

a (n

euro

cy­

tom

a)

18

Bol

en e

t al

. [9

], 1

989

: ce

ntra

l neu

rocy

tom

a 19

Pat

il et

al.

[ 1 OJ

, 199

0:

neur

ocyt

oma

20

15

22

22

24

30

39

66

32

34

con

tra

st e

nhan

ce-

men

t

M

Hea

d tr

aum

a (in

cide

ntal

) La

tera

l ve

ntric

le

-

F

Incr

ease

d IC

P

Late

ral

and

third

-

vent

ricle

s F

In

crea

sed

ICP

La

tera

l ve

ntric

le

-

M

Incr

ease

d IC

P

Late

ral

and

third

-

vent

ricle

s M

In

crea

sed

ICP

La

tera

l and

thi

rd

-ve

ntric

les

F

Inci

dent

al h

ead

trau

ma

Late

ral v

entr

icle

-

M

Incr

ease

d IC

P (

head

ache

, T

hird

ven

tric

le

dem

entia

, ata

xia)

C

alci

ficat

ion

(hyp

er­

dens

e on

une

n­ha

nced

sca

n);

dens

e en

hanc

e­m

ent

F

Incr

ease

d IC

P (

seve

re

head

ache

)

M

Incr

ease

d IC

P (

naus

ea.

vom

iting

, diz

zine

ss, i

n­te

rmitt

ent

visu

al l

oss)

, se

izur

e

Late

ral

vent

ricle

La

rge

calc

ified

m

ass

; hom

ogen

e­ou

s en

hanc

emen

t

Late

ral

vent

ricle

C

alci

ficat

ion

; min

i­m

al e

nhan

cem

ent

No

t pe

rfor

med

Not

per

form

ed

No

t pe

rfor

med

Not

per

form

ed

No

t pe

rfor

med

Not

per

form

ed

Not

per

form

ed N

ot

perf

orm

ed

Not

per

form

ed N

ot

perf

orm

ed

Not

per

form

ed N

ot

perf

orm

ed

Not

per

form

ed N

ot p

erfo

rmed

N

o m

entio

n o

f sy

n­ap

ses

on E

M

Ava

scul

ar

T1:

isoi

nten

se r

ei-

Occ

asio

nal

syna

ptic

at

ive

to b

rain

te

rmin

als

, num

erou

s w

ith a

reas

of

neur

onal

cel

l pr

oc-

hypo

inte

nsi

ty

esse

s w

ith m

icro

tu-

(cal

cium

); P

O

buie

s an

d de

nse

and

T2

: inh

o-co

re v

esic

les

mog

eneo

us in

-cr

ease

d si

gnal

in

tens

ity

Not

per

form

ed T

1:

isoi

nten

se r

ei-

Num

erou

s ne

uriti

c at

ive

to c

orte

x;

proc

esse

s w

ith m

i-P

D a

nd T

2:

crot

ubul

es a

nd

isoi

nten

se r

ela­

tive

to c

ort

ex

, la

rge

vasc

ular

flo

w v

oids

dens

e co

re g

ranu

les;

no

syn

apse

s pr

esen

t

Tot

al r

esec

tion

Aliv

e at

7 m

onth

s;

no r

ecur

renc

e

Tot

al r

esec

tion

; rad

iatio

n A

live

at 2

9 m

onth

s;

ther

apy

no r

ecur

renc

e P

artia

l re

sect

ion

; rad

ia-

Aliv

e at

19

year

s;

lion

the

rapy

n

o r

esid

ual

tum

or

Tot

al r

ese

ctio

n A

live

at 4

1 12 y

ears

; no

rec

urre

nce

Tot

al r

esec

tion

; rad

iatio

n A

live

at 1

5 m

onth

s;

ther

apy

no r

ecur

renc

e P

artia

l res

ectio

n; r

adia

-A

live

at 1

5 m

onth

s;

tion

ther

apy

no r

esid

ual t

umor

P

artia

l res

ectio

n; r

adia

-A

live

at 2

5 m

onth

s;

lion

the

rapy

re

sidu

al t

umor

pe

rsis

ted

Tot

al r

esec

tion

Sub

tota

l re

sec

tion

Tot

al r

esec

tion

Aliv

e at

4 y

ears

; no

recu

rren

ce

Fol

low

-up

inte

rval

no

t re

port

ed

Fol

low

-up

inte

rval

no

t re

port

ed

>

"­ z ::0 "' "­ c -< >

c <D

c ~

<D

<D z m

c :Il 0 0 -<

-l

0 ~

)>

~

=i

I z -l

:Il

)>

<

m

z -l

:Il 0 c r )>

:Il

I m

~

0 :Il

:Il

I )>

G) m

---J

(j)

<.

D

770

u;O £; E c ::J o-Ero

::J

"'" -r- ·u; -a> "'~ Q)0

.::= c <(

c o>­·.;::; a. u"' Q) ~ <J) Q) Q).C ~-- c "'0 o ·z ~~ (/)

0 c<: 0 Q) ., E ~ Q)

:Q~ m.c u c oiD z Q)

TI ·c c Q) > ro a;

"' _J

Q) .c u "'­"Oc "'0 £_ :~ 0..-o g~

~.2 <J).o

"'" Q) c t;"' _s

LJ...

::, Q) c

o; Ol

-"' :Jl E "'0 u:;, c u Q) e <J)

ct

iJi .c c~ 0 c E ~ a~

~ i3 - Q) "'~ IDO .::= c <(

0 cc 0 Q)

-=E ~ Q)

~~ m.c u c 0 Q)

z

·c c Q) >

~ 2a> .!QU _J

~ E Q) .c ~

"' :; u ·c c Q) Q) Ol > "' m.c .::~ _s

:2

<D

"'

"' "'

SMOKER ET AL. AJNR :12, July/August 1991

studies in the patients summarized in Table 1 revealed that none had died from tumor growth or recurrence, and survival time was as long as 19 years . This is in contrast to the typical parenchymal neuroblastoma occurring in young children, for which the overall 3-year survival rate is only 60% [11] . Neu­rocytomas usually arise from the septal region , to which they may be adherent [7] . Complete surgical resection , if possible, appears to be curative [5] . The benefits of adjunctive radiation therapy or chemotherapy in the treatment of these lesions is unclear.

Neurocytomas may be difficult to distinguish from other intraventricular tumors, such as ependymomas, oligodendro­gliomas, or meningiomas, which may have similar character­istics on imaging studies. Although neurocytomas are uncom­mon intraventricular tumors and rarely bleed , they should be considered in the differential diagnosis in patients with intra­ventricular hemorrhage.

REFERENCES

1. Hassoun J, Gambarelli D, Grisoli F, et al. Central neurocytoma: an electron­microscopic study of two cases. Acta Neuropathol (Berl) 1982;56 : 151 - 156

2. Jerdan MS, White CL, Solomon D, Scheithauer BW, Clark AW. Differen­tiated cerebral neuroblastoma in adults. J Neuropathol Exp Neurol 1983;42 :305

3. Pearl GS, Takei Y, Bakay RAE, Davis P. Intraventricular primary cerebral neuroblastoma in adults: report of three cases. Neurosurgery 1985;16:847-849

4. Wilson AJ, Leafier DH , Kohout NO. Differentiated cerebral neuroblastoma: a tumor in need of discovery. Hum Patho/ 1985;16 :647-649

5. Townsend JJ , Seaman JP. Central neurocytoma-a rare benign intraven­tricular tumor. Acta Neuropathol (Berl) 1986;71: 167-1 70

6. Poon TP, Mangiardi JR , Matoso I, Weitzner I. Third ventricular primary cerebral neuroblastoma. Electron microscopic and immunohistochemical study. Surg Neuro/1988;30:237-241

7. Nishio S, Tashima T, Takeshita I, Fukui M. Intraventricular neurocytoma: clinicopathological features of six cases. J Neurosurg 1988;68: 665- 670

8. Ferreol E, Sawaya R, de Courten-Myers GM. Primary cerebral neuro­blastoma (neurocytoma) in adults. J Neurooncol 1989;7: 121-128

9. Bolen JW, Lipper MH, Caccamo D. Intraventricular central neurocytoma: CT and MR findings. J Comput Assist Tomogr 1989;13:495-497

10. Patil AA, McComb RD, Gelber B, McConnell J, SasseS. Intraventricular neurocytoma: a report of two cases. Neurosurgery 1990;26: 140-144

11 . Bennett JP, Rubinstein LJ . The biological behavior of primary cerebral neuroblastoma: a reappraisal of the cl inical course in a series of 70 cases. Ann Neuro/1 984;16:21-27