Introduction
Chordoid glioma is a rare, low-grade tumor (WHO II) of the third ventricle, first
described by Brat in 1998.[1] Its imaging features are difficult to distinguish from other more common lesions
in this location. There are only 83 cases described so far in the literature.[2]
[3]
[4]
Due to the location of these tumors, they usually present with symptoms of intracranial
hypertension caused by obstructive hydrocephalus, hypothalamic dysfunction and/or
visual deficit.[2] Gross total resection (GTR) is the treatment of choice, since no recurrence has
been reported after a macroscopically complete resection; however, this is not always
possible because of the location of the tumor and its adherence to the hypothalamus.[3] Mortality in the immediate postoperative period after surgical resection can be
as high as 29%.[1] The major causes of death, namely, pulmonary embolism, myocardial infarction and
infection,2 are not directly related to the surgical procedure.
To the best of our current knowledge, our case is the first report of a spontaneous
brainstem hemorrhage as cause of death after surgical excision of a chordoid glioma.
Case Report
Presentation: The patient is a 71-year-old man with history of an accidental trauma to the left
eye, which resulted in complete blindness, and also a previous right eye catarac,
that presented with an 8-month progressive visual loss in the right eye. He was referred
to neurosurgery by his ophthalmologist, who did not believe the visual impairment
was related to the cataract.
He had no other complaints, no relevant past medical history, or use of chronic medication.
Apart from the right temporal hemianopia, the neurological examination was unremarkable.
Physical stigmas of pituitary dysfunction were also excluded.
The computerized static perimetry (CSP) exam confirmed right temporal hemianopia and
- left-eye amaurosis (sequelae of a previous accident)
A head magnetic resonance imaging (MRI) revealed an extra-axial, suprasellar, mass
lesion, isointense on T1-weighted images, hyperintense on T2, and with heterogeneous
strong enhancing after gadolinium contrast administration, except for a small cystic
focus located in the inferior margin. Its dimensions were 5 cm in vertical diameter,
2.7 antero-posterior, and 1.7 in lateral. It was localized over the pituitary stalk,
but with no correlation to the pituitary gland, displacing the optic nerves laterally,
and compressing the chiasm. The first diagnostic hypothesis was of a craniopharyngioma
([Fig. 1A-C]).
Fig. 1 Gadolinium-enhanced T1 weighted MRI images, sagittal (A), axial (B) and coronal (C), depicting an extra-axial, suprasellar mass lesion, with strong heterogeneous enhancement,
except for a small cystic focus located in the inferior margin. The lesion is 5 × 2.7 × 1.7
cm in vertical, the antero-posterior and transverse axis respectively. It is laterally
displacing the optic nerves and compressing the optic chiasm.
Treatment: The patient was submitted to surgery, and gross total resection was apparently achieved
using a transSylvian and a trans-lamina terminalis approach. The pituitary stalk had
to be sacrificed.
Histological examination revealed a chordoid glioma of the third ventricle with positive immunohistochemistry
for vimentin, glial fibrillary acidic protein (GFAP), cell antigen CD 34 and negative
for cytokeratin MNF 116 and S100. The index of monoclonal antibody Ki-67 was lower than 1% ([Fig. 2]).
Fig. 2 (A) – Hematoxylin-Eosin (HE), 200x, ventricular tumor lined up by a fibrous capsule;
(B) – HE, 400x, tumor cell cords surrounded by myxoid stroma; (C) – HE, 400x, solid tumor areas with lobule formation, abundant lymphocytes and Russell
bodies; (D) –HE, 400x positive immunoreactivity for glial fibrillary acidic protein (GFAP) in
chordoid glioma tumor cells.
Postoperative course: The postoperative computerized tomography (CT) scan showed apparent GTR, and no associated
complications ([Fig. 3]). Although we are aware that complete excision of the lesion can only be confirmed
by MRI, our department's strategy with brain tumors is to perform this imaging exam
at 2 months post surgery. The patient had no immediate postoperative additional morbidity,
and was discharged from the hospital after three weeks. Two days later, he had an
unexpected hypertensive crisis that resulted in extensive brainstem hemorrhage and
subdural hematoma. Unfortunately, the patient did not survive. ([Fig. 4])
Fig. 3 Axial non-contrast enhanced CT scan showing apparent gross total resection of the
third ventricle tumor lesion, with no associated complications.
Fig. 4 Axial non-contrast enhanced CT scan three weeks after surgery revealing an extensive
brainstem hemorrhage (A) and a left massive subdural hematoma associated with mass effect and subfalcine
herniation (B) that resulted in the patient's death.
Discussion
Chordoid Glioma is a rare low-grade tumor that is always found in the third ventricle.
It is unique in its topography, female gender predominance, stereotypical histology
and radiological features. Because of the singular features of chordoid gliomas, these
tumors are difficult to group with other neoplasms, and this is why they are included
in the other gliomas section of the recently published 2016 WHO classification of brain tumors.[5]
To date, 83 cases of chordoid glioma have been reported in the literature.[2]
[3]
[4]
Chordoid gliomas occur in adult patients with a mean age of 46 years, and with a 2:1
female predominance. There are only 3 reports of a chordoid glioma in children: a
12-year-old boy[6] and two girls, one aged 7, and the other 13.[7]
[8]
The presenting symptoms reported are headache and vomiting, visual disturbances, gait
difficulties, fatigue, syncopal episodes, urinary incontinence, weight gain, hyperphagia,
hypothyroidism, memory loss and psychosis.[9] These symptoms are not specific, and are related to the coexisting hydrocephalus,
or are due to the invasion in or mass effect on surrounding structures such as the
hypothalamus, optic the chiasm or the fornices. Calanchini et al[3] described a unique form of presentation, so far consisting of a chordoid glioma
presenting with hyponatremia due to the inappropriate secretion of the antidiuretic
hormone (ADH). Most patients present with several months or even years of clinical
history.[9] There is only one report by Gallina et al of an incidentally diagnosed chordoid
glioma after a minor head injury.[10]
Our case has some rare features. It is a case of a male patient, older (71 years old)
than the usually described patients, with a previous eye pathology, in which the diagnosis
of the chordoid glioma was most likely precipitated by the accidental ocular trauma
that resulted in left eye blindness. In our interpretation, the patient probably already
had some visual deficit for several months, or even years, but did not complain about
it. Only after the accident, being blind in the left eye, he noticed he was also losing
vision of his only useful eye (right). The difficulty in this case, besides the advanced
age of the patient, was also the lack of other symptoms. The outcome after discharge
from the hospital three weeks after the operation was also totally unexpected.
According to Pomper[11], chordoid gliomas are ovoid in shape, well circumscribed, located in the anterior
third ventricle, and separated from the pituitary gland. They are isointense on T1-weighted
images, and are uniformly enhanced after gadolinium contrast administration. Most
tumors are solid, but in 25% of them, a small central cystic area is present. The
differential diagnosis includes other third ventricular lesions, such as craniopharyngioma,
ependymoma, central neurocytoma, pituitary macroadenoma, choroid plexus papilloma
and meningioma. In our case, due to the advanced age of the patient and the cystic
aspect of the lesion in the MRI, the first diagnostic hypothesis was a craniopharyngioma.
Additionally, our case is included in the rarer 25% of chordoid gliomas that present
with a central cystic area.
Similar to the majority of the reports in the literature, in our case, the histopathological
exam revealed a chordoid glioma immunohistochemically stained for GFAP, vimentin,
CD 34 and epithelial membrane antigen (EMA), and negative reactivity for MNF 116 and
S100, with Ki-67 lower than 1%. Lastly, we also observed positive immunoreactivity for D2–40 and
negative for neurofilament protein (NFP). Monoclonal antibody D2–40 is known to act
against M2A protein derived from germ cell tumors, which makes it a useful marker
for ependymal tumors, especially when combined with EMA.[12]
This way, in our case, adding the positive immunoreactivity for D2–40, for EMA and
GFAP and the negativity for NFP points to a more likely ependymal origin of chordoid
gliomas, as described in the majority of the previous reported cases in the literature.
Gross total resection is the treatment of choice for chordoid gliomas, since no recurrence
has been reported after a macroscopically complete resection, but this is often difficult
because of the size and location of the tumor and its adherence to the hypothalamus.[3] When this is the case, the risk of surgical morbidity cannot be ignored.
Other authors have suggested that a less invasive surgical treatment, with or without
the addition of gamma knife radiosurgery, can provide a safer and more effective therapeutic
approach to these lesions.[13]
However, previous reports show that, when not completely resected, chordoid gliomas
can continue to grow slowly, and some patients have a poor outcome;[14]
[15] so, whenever possible, in our perspective, GTR should be the goal.
Additionally, in a recent review by Ampie et al[2] that gathered 81 cases of surgically treated chordoid gliomas, there were 31 patients
(37%) suffering from postoperative complications, and 18 (22.2%) deaths, none related
to tumor progression. Although reported morbidity and mortality were considerably
high, there was no association with the extent of resection, age or tumor size. Moreover,
patients in whom GTR was achieved had no tumor progression, while a progression of
25% and 14.7% was noted after biopsy and subtotal tumor resection (STR) respectively.
In the same review, when comparing the transcortical and transcallosal approaches
with the trans-lamina terminalis approach, this last one showed a strong trend towards
decreased overall rates of postoperative morbidity, although this difference did not
achieve statistical significance (p = 0.051).
In our case, GTR through a transSylvian trans-lamina terminalis approach was possible.
The patient was discharged from the hospital three weeks later, with no major postoperative
complications. He was started on hormonal therapeutic substitution due to hypopituitarism,
a consequence of pituitary stalk section during surgery, but besides that, the patient
had no additional morbidity. However, 48 hours later he had a major brainstem hemorrhagic
stroke associated with a subdural hematoma, following a hypertensive crisis, and unfortunately
died. There was no trauma related to the event. This was totally unexpected and, to
the best of our knowledge, it is the first case described in the literature of a hemorrhagic
stroke as a cause of death after surgical resection of a chordoid glioma.
Previous reports on death causes after chordoid glioma surgery reach as high as 18
cases (22.2%) out of 81 patients, and 50% (9 patients) of them died in the first 18
days after surgery.[2] Most patients died from pulmonary embolism, infectious causes or myocardial infarction.
No death related to the disease's progression was reported.
There are three reports of postoperative hematoma after chordoid glioma surgery,[7]
[13]
[16] and none resulted in the patient's death. In one report, the patient had an intraventricular
bleeding that was surgically evacuated, but the patient died one week later, from
another cause, namely bacterial meningitis.[7] In another case, there was a small subfrontal hematoma, but with no further consequence
for the patient.[13] Another report of a postoperative subdural hematoma and hemorrhage in the surgical
field was managed conservatively, and the patient recovered after one week.[16]
We can only speculate about what caused this major brainstem hemorrhage and subdural
hematoma that eventually resulted in our patient's death. There was no associated
head trauma, the patient was lying in his bed when a neurological deterioration was
noted. The patient had no previous history of hypertension before surgery, so maybe
the hypertensive crisis was a consequence of the iatrogenic hormonal imbalance that
followed the GTR of the tumor accompanied by the section of the pituitary stalk. Although
hormonal substitution treatment was started, this must have interfered with the arterial
blood pressure regulation mechanisms and, associated with the advanced age of the
patient and vascular fragility, ended up causing a major hemorrhagic stroke and subdural
hematoma.
Conclusions
The third ventricle chordoid glioma is an uncommon tumor with an uncertain origin;
however, it must be considered in the differential diagnosis of third ventricle tumor
lesions, even in older male patients.
Although surgical resection, especially GTR, is considered the gold standard, the
high morbidity and mortality associated with the procedure cannot be ignored. For
older and other high-risk patients, planned subtotal resection followed by stereotactic
radiosurgery may be a safe, effective alternative, and should be taken into account.
For this issue, further studies, with longer follow-up periods are needed to understand
the role of radiotherapy and radiosurgery in the management of these tumors.
Furthermore, even though the immediate postoperative course might be uneventful, major
complications resulting in patient death seem to occur after the second postoperative
week. Therefore, close surveillance of these patients is advised in the first weeks
after surgery, especially regarding hormonal substitution and thromboembolic event
prophylaxis.
