11 / 99
T
reatment
of
medulloblastoma
in
children
and
adolescents
R
ev
A
ssoc
M
ed
B
ras
2016; 62(4):298-302
299
C
linical
questions
1. W
hat
is
the
natural
history
of medullo
-
blastoma
in
children
and
adolescents
?
The search strategy is described in Annex I. There are few
articles describing its natural history. The electronic search
found 22 publications, whose final evaluation revealed
two papers describing the natural history in adults and
two in children. Three other works derived from the study
of references and knowledge of the authors.
Data extraction
•
•
Importance of the age:
Among children and adoles-
cents with medulloblastoma, children under three
years of age have worse prognosis than those older than
that.
3
•
•
Degree of tumor differentiation:
The degree of dif-
ferentiation of tumor tissue is important for survival.
In one study, patients with 90% or more of undiffer-
entiated total tumor tissue exhibited extremely poor
prognosis (with none of the nine patients operated re-
maining alive after 3 years) in contrast with 60% sur-
vival in patients with tumors that showed levels of dif-
ferentiation below 90%.
3
(C)
•
•
Disease-free interval after treatment:
After treat-
ment, disease-free survival at 5 years reached 54% in
one study.
2
(C)
Tumor recurrence, if any, occurs be-
fore eight years of treatment.
Severity of hydrocephalus, size of the tumor, and pres-
ence of brain-stem invasion were not correlated with
prognosis.
4
(D),
5
(C),
6
(C) (C)
Recommendation
It is recommended to consider the medulloblastoma as
serious illness. In children under 3 years with undiffer-
entiated tumors, survival is lower. Children older than
3 years with less anaplastic tumors have better survival
rates.
(C)
2. I
s
complete
resection
of medulloblastoma
required
?
Studies comparing partial and complete resections were
evaluated. The search strategy was described in Annex I.
960 articles were found from the electronic search. Of
these, 12 articles were initially selected based on the title.
Seven articles were selected based on summaries. The Sol-
heim article was excluded as it describes comparisons of
mortality among regions in the same country.
Data extraction
Lang et al.
7
(C)
published a series of cases with retrospec-
tive analysis in children older than six months with brain
tumor. There were four patients with primitive neuroec-
todermal tumors/medulloblastoma. There were two in-
traoperative deaths among 16 cases operated. Of the 14
survivors, four had total resections. One patient with me-
dulloblastoma underwent complete resection (>90%) and
was treated with chemotherapy and radiotherapy. Sur-
vival lasted 1.2 years and, in terms of neurological status,
psychomotor development was impaired, the child was
not able to crawl or stand, could speak a few words, and
did not present neuropsychological improvements dur-
ing development. Another patient was operated at the
age of 1.4 months, survived for six months and under-
went ventriculoperitoneal shunt as adjunctive therapy
only. The authors describe four cases of medulloblasto-
ma in the series but the result of only two of the patients.
Raimondi and Tomita
8
(C)
studied 22 patients. Com-
plete resection was performed in 13 patients, while nine un-
derwent subtotal resection. By then, the patients were stud-
ied by CT scans and myelogram. All the patients treated
with complete resection were alive at the time when these
results were published, as well as 3 out of 9 who underwent
partial resection. They all underwent radiotherapy.
Wang et al.
9
(C)
conducted a retrospective study of
52 patients for analysis of prognostic factors. The results
of univariate analysis showed that the greater the extent
of resection, the better the prognosis. In multivariate anal-
ysis, the extent of resection had no significance.
Monteight et al.
10
(C)
studied a series of 166 cases of
brain tumor in children. Thirty-six cases were medullo-
blastoma and were sorted according to the extent of re-
section: Complete resection, 16 cases; incomplete resec-
tion, 14 cases; biopsy, six cases. Patients with complete
resection of medulloblastoma had higher survival than
those undergoing incomplete resection and/or biopsy.
Recommendation
There is evidence
(C)
that complete resection improves sur-
vival. Complete resection is recommendedwherever possible.
3. W
hen
does
the
residual
tumor
,
in
me
-
dulloblastoma
,
need
to
be
operated
after
the
first
surgery
?
124 articles potentially related to our research were iden-
tified. Ten were initially selected based on title and sum-
mary.
10-20
No article specifically investigated the effect of
reoperation on residual tumor.