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M. Reni et al. / Critical Reviews in Oncology/Hematology 63 (2007) 81–89 85
may have a somewhat better prognosis with 5-year survivals
of 55–90% as compared to paediatric patients, i.e.14–60%
n general, the younger the child the worse
the prognosis t has been suggested that paedi-
atric ependymomas may behave more aggressively, based on
the more immature neural tissue of the children if-
ferent patterns in cytogenetic aberrations between younger
and older patients may underlie the age-related outcome
The role of tumour location is also controversial. If spinal
lesions are related to the most favourable outcome, things are
less clear for intracranial tumours. Some authors reported no
prognostic impact of this variable Accord-
ing to others, supratentorial ependymomas are related to a
worse prognosis because they more often exhibit periph-
eral infiltrative growth into the brain parenchyma and are
less often entirely encapsulated rendering surgical resectabil-
ity troublesome urthermore, infratentorial
tumours show a lower mitotic activity than supratentorial
tumours Conversely, other authors claimed a worse
prognosis for ependymomas arising from the posterior fossa,
which occur in younger patients nd invade the brain-
stem, the floor of the fourth ventricle or cranial nerves of
the cerebellopontine angle through the foramen of Luschka,
precluding complete resection The 5-year survival
ranges between 35% and 76% for supratentorial, 40% and
59% for infratentorial, and 57% and 100% for spinal ependy-
momas The extent of resection has been
proposed as an independent prognostic factor. Gross total
resection achieves a better 5-year survival than a subtotal
removal or biopsy In some cases, the benefit of
complete resection was limited to low-grade tumours
However, most authors failed to find any significant survival
advantage related to the extent of resection
The lack of evidence for the impact of surgery on survival
could be related to the unreliability of subjective assess-
ment of the degree of surgical ablation By contrast, the
degree of resection, when assessed by postoperative imaging,
revealed a significant difference in 5-year freedom from pro-
gressive disease in a small series of 19 patients Female
gender was reported to show better survival than male gender
in one single series
6. Treatment
6.1. Surgery
Surgery represents the standard treatment for ependy-
moma; it provides tissue for histologic diagnosis, may
re-establish cerebrospinal fluid flow, and permits debulking
or total resection of the tumour. Maximal surgical resec-
tion can be of paramount importance and should be carried
out whenever possible, without compromising neurological
function, and a positive relation between extent of imaging-
based surgical resection and outcome has been suggested
Postoperative magnetic resonance imaging allows a
better evaluation of the degree of resection and may also iden-
tify cases in whom immediate second-look surgery might
be useful. Significant improvements in neurosurgical tech-
niques and neuro-anesthesia have facilitated a reduction
of operative mortality of 25–50% for infratentorial and of
6–22% for supratentorial ependymomas to less than 5% of
cases Incomplete resection is the rule because
ependymomas usually grow in highly specialised areas of the
central nervous system. The frequency of complete resections
is higher in surgical series than in radiotherapy series and
ranges from 25% to 93% for supratentorial ependymomas
nd from 5% to 72% for infratentorial ependy-
momas he rate of gross total
resections in infratentorial tumours depends on their location,
being up to 100% in the roof of the fourth ventricle, 86% in
mid-floor tumours and 54% in the lateral recesses pinal
cord tumours, which in the majority are low-grade lesions,
can often completely be removed, and without functional
sacrifice in 27–45% of cases
6.2. Radiation therapy
Postoperative radiotherapy (RT) is the standard treatment
on a type C basis in high-grade ependymomas, and on a type
3 basis in low-grade ependymomas. Five-year survival rates
for patients with intracranial ependymomas have increased
from 0–27% 36.5–87% since the use of systemic irra-
diation ow-
ever, data on survival after surgery alone are limited inmodern
series and a clear impact of radiotherapy on the outcome is
not supported by consistent statistical data because no ran-
domised trials have been carried out. The non-significant
prolonged survival with postoperative irradiation as observed
in retrospective series was either uncontrolled or compared
with historical controls hile in the single series
reporting a significant benefit, the comparison was biased
due to inclusion of patients experiencing progressive dis-
ease during postoperative chemotherapy, or patients younger
than 3 years of age in the control arm Notwithstand-
ing these considerations, particularly since failure to control
local disease remains the most significant factor contribut-
ing to recurrence and a poor survival, there is a consensus
that radiotherapy should be part in the standard of care
for the majority of patients. More recently, some small
series reported a remarkably good outcome in children with
low-grade intracranial ependymoma and did not receive irra-
diation after a gross total resection
The option of a close observation and delaying radiation
until signs of tumour progression may be relevant, since late
effects as cognitive deterioration, endocrine dysfunction in
small children or dementia in the elderly constitute major
concerns in patients who are potential long-term survivors of
brain tumours. So, reserving RT for relapses appears to be an
attractive strategy in these patients. It may also be considered
as a therapeutic option for patients with a subtotal resection
of low-grade ependymomas, assuming that the behaviour of