Ki67 approximately 8–10 % proliferative index.Īll of these features favored the diagnosis of glioblastoma WHO Grade-IV.

Immunohistochemical studies were performed by DAKO envision method using the following antibodies: Mitosis of approximately 3–4/10 HPF was noted. Patchy areas of palisading necrosis were also seen. Histopathology revealed fragments of neoplastic lesions showing dense cellularity composed of markedly atypical cells with abundant eosinophilic cytoplasm and pleomorphic enlarged nuclei with vesicular chromatin and prominent nucleoli. His central nervous system examination was the same as the preoperative examination, and hence, he was discharged and followed up as an outpatient in the clinic. Postoperatively, the patient remained stable with no new neurology. After taking a biopsy, intracapsular tumor debulking was done with the help of an ultrasonic aspirator and near-total resection was achieved with the possible removal of all visible tumor mass. The cerebellar invasion was evident along the medial aspect along with dense adhesions between the capsule and lower cranial nerves. It was encapsulated and firm in consistency. Cerebellum was retracted with the help of a Duro retractor and the tumor was identified. The cerebellomedullary cistern was opened followed by drainage of cerebrospinal fluid. After fixing the patient’s head in the Mayfield head clamp, retrosigmoid craniotomy was done and surgery progressed in a usual fashion. We positioned the patient in a park bench position with the right side facing up. Based on the abovementioned findings, a diagnosis of vestibular schwannoma was made preoperatively. The lesion was about 4 × 5 cm in size, compressing the ipsilateral cerebellar hemisphere and 4 th ventricle. Magnetic resonance imaging (MRI) of the brain with contrast showed a lesion in the right CPA, hypointense on T1-weighted sequences, hyperintense on T2-weighted sequences, and demonstrated homogeneous enhancement on T1 postgadolinium contrast images, with characteristic trumpet sign. His neurologic examination revealed a horizontal left beating nystagmus, right-sided sensorineural hearing loss, and no other cranial nerve dysfunction, however, Romberg’s test was positive with impaired tandem walking. There was no complaint of altered level of consciousness, fits, falls, no visual symptoms, or facial weakness. Symptoms had become severe over the past 2 months making him completely deaf in the right ear. This is the case of a 65-year-old male, with no known comorbid, who presented through outpatient clinic with the complaints of right-sided deafness, peripheral vertigo associated with vomiting, and progressive headache for the past 5 months. Keywords: Glioblastoma, Internal acoustic meatus, Cerebellopontine angle, Vestibular schwannoma Hence, despite being very rare, they should be considered as a differential in tumors at CPA. The final histopathology report showed glioblastoma multiforme.Ĭonclusion: As per our knowledge, this is the fourth reported case of an extra-axial VIII cranial nerve glioblastoma located in internal auditory canal. Maximum safe resection (near total) was done. His preoperative magnetic resonance imaging findings were consistent with vestibular schwannoma. We report the fourth case of primary internal auditory canal/cerebellopontine angle (CPA) glioblastoma which initially mimicked vestibular schwannoma on the basis of its location and presentation.Ĭase Description: A 65-year-old male presented with headache, vertigo, and progressive right ear deafness for 5 months. The presence of true extra-axial GBM infratentorially, especially in the internal auditory canal, is extremely rare with only three cases reported previously in the literature. Background: Glioblastomas are the most common adult primary brain tumor present supratentorially.

Decompression internal auditory canal