Key-words:
Double tumors - glioma - meningioma
Introduction
Multiple primary brain tumors are usually seen in the presence of genetic disorders
such as neurofibromatosis, tuberous sclerosis, or in patients who have received radiotherapy.[[1]] In the absence of such factors, multiple primary brain tumors, especially at adjacent
sites, are rare. We present a case of a 51-year-old male patient who presented to
us after a single episode of generalized tonic-clonic seizure and was finally diagnosed
with “adjacent site” anaplastic oligodendroglioma and meningioma. This is only the
second such case reported in literature.
Case Report
A 51-year-old male presented to us with a complaint of one episode of generalized
tonic-clonic seizure 15 days ago. The seizure was associated with loss of consciousness
for 10 min and jerky movements of all four limbs. There was no history of aura, postictal
headache or weakness, tongue bite, or loss of continence associated with it. On examination,
he had no neurological deficit. There were no neurocutaneous markers. Magnetic resonance
imaging brain [[Figure 1]] revealed an ill-defined area of altered signal intensity in the right frontotemporal
and insular region which was hypointense on T1, hyperintense on T2 with patchy areas
of enhancement suggestive of a high-grade glioma. Another avidly enhancing lesion
dural-based extra-axial lesion was overlying right temporal lobe (adjacent to the
other lesion) suggestive of a meningioma.
Figure 1: (a) Magnetic resonance imaging brain Tl-weighted image showing a hypointense right
insular lesion (asterisk) and an isointense dural-based lesion (arrow). (b and c)
Contrast Magnetic resonance imaging image showing strongly enhancing dural-based lesion
suggestive of a meningioma (arrow) and an heterogeneously enhancing lesion in right
insular region suggestive of a glioma (asterisk)
Under neuronavigation, the patient underwent the right frontotemporal craniotomy.
After reflecting the dural flap anteroinferiorly, a dural-based lesion was seen attached
to the temporal dura and extending into sylvian fissure suggestive of meningioma [[Figure 2]]. The sylvian fissure was opened up due to lesion. The other tumor was intra-axial,
soft, grey-white, suckable, moderately vascular, and extended into frontal operculum
and temporal lobe around the right middle cerebral artery suggestive of high-grade
glioma. Postoperative period was uneventful, and the patient was discharged on postoperative
day 6. On histopathological examination [[Figure 3]], the dural-based lesion revealed a tumor composed of sheets and whorls of spindle
cells. There was mild nuclear atypia. Few psammoma bodies were also present. These
findings were suggestive of Grade 1 meningioma. The intra-axial lesion revealed a
moderately cellular tumor composed of sheets of tumor cells with a fibrillary background.
There was moderate nuclear atypia with increased mitotic activity. On immunohistochemistry,
tumour cells were positive for glial fibrillary acidic protein, p53. Ki-67 was 12%–15%.
The findings were suggestive of anaplastic oligodendroglioma (Grade 3).
Figure 2: Intraoperative image showing the dural-based meningioma extending into the sylvian
fissure (arrow)
Figure 3: (a) Highly cellular tumor with perinuclear halos and capillary network in the background.
Brisk mitosis (arrow) is seen. (H and E, x40) suggestive of an anaplastic oligodendroglioma.
(b) Ki67 immunohistochemistry showing high proliferative activity. (c) Meningioma
with sheets and whorls of tumor cells. Psammoma bodies are seen (H and E, *20)
Discussion
Multiple intracranial tumors are extremely rare. They are more commonly seen in patients
with genetic disorders such as neurofibromatosis or tuberous sclerosis.[[1]] They may also be seen in patients who have received radiotherapy treatment.[[1]] The incidence of primary brain tumors with different histology is 0.3% of all brain
tumors.[[1]] The most frequently occurring combination is that of meningioma and glioma, followed
by meningioma and neurinoma and meningioma and pituitary adenoma.[[1]] Even though meningioma along with glioma is the most frequently occurring combination,
its occurrence at adjacent sites has been reported by only a few authors [[2]],[[3]],[[4]],[[5]],[[6]],[[7]],[[8]],[[9]],[[10]] [[Table 1]]. More so, occurrence of an oligodendroglioma adjacent to a meningioma is even rarer,
this case being only the second such case available in the English literature.[[2]]
Table 1: Summary of reported cases of "adjacent site" glioma and meningioma
Various hypotheses have been proposed to explain the occurrence of this rare phenomenon.
Since meningiomas and gliomas are the most commonly occurring primary brain tumors,
most authors feel that this concurrence of meningioma and glioma at adjacent sites
is a mere co-incidence.[[1]],[[6]],[[7]] Certain genetic factors, exposure to chemicals, trauma, or some immunological mechanism
may be responsible for this phenomenon. Some are of the opinion that a locally acting
oncogenic paracrine factor from meningioma may induce malignant transformation in
adjacent brain parenchyma and glial cells.[[6]] Similarly, irritative effects from low-grade glioma may induce meningeal proliferation.
Exact mechanism is, however, yet to be elucidated.
In such cases, it is usually not possible to make a preoperative diagnosis of “double
tumors.” One must be aware of the possibility of such an entity and suspect it if
perilesional edema does not correlate with the presence of a single benign lesion
or intraoperatively the tumor does not correlate with preoperative radiology. In certain
cases, perilesional edema in meningioma may mask a small low-grade astrocytoma. Biopsy
helps to provide tissue diagnosis in such cases.
Conclusion
Multiple primary brain tumors are rare in the absence of predisposing factors such
as genetic disorders or radiotherapy. A surgeon must be aware of the entity “adjacent
site” double tumors when radiological and intraoperative findings do not corroborate.
Biopsy helps to confirm the diagnosis in these cases.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms.
In the form the patient(s) has/have given his/her/their consent for his/her/their
images and other clinical information to be reported in the journal. The patients
understand that their names and initials will not be published and due efforts will
be made to conceal their identity, but anonymity cannot be guaranteed.
