Pontine extension of a tentorial schwannoma without cranial nerve involvement: a case report

Abstract

IntroductionIntracranial schwannomas unrelated to the cranial nerves are uncommon. We report a new case of tentorial schwannoma unrelated to the cranial nerves, with extension into the pons. A literature review with discussion of the most relevant pathogenetic aspects is also performed.Case presentationA 42-year-old Caucasian man was admitted with right-sided paresthesias and weakness of his upper and lower extremities. The neurological examination revealed right hemiparesis and hemi-hypoesthesia. A brain magnetic resonance imaging scan revealed a cerebellopontine lesion, arising from the left free edge of the tentorium, and extending into his pons. A piecemeal removal was performed through a retrosigmoid approach. The lesion was not found to be associated with any cranial nerves. The histological examination revealed a schwannoma Antoni type A. His postoperative course was uneventful. At one year follow-up, the patient was neurologically intact and the magnetic resonance imaging of his brain performed at that time showed complete removal without signs of recurrence.ConclusionTentorial schwannomas are rare clinical entities. Knowledge of their clinical, radiological and anatomical characteristics is very important for the correct diagnosis and management.

Tentorial ectopic schwannoma: A case report and literature review

“…Since the first case was reported by Flickinger et al. in 1988 [6] , we collated only 18 patients with TES all over the world, including this case ( Table 1 ) [1 , [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] . It is popular to occur in children and young adults, and no significant differences are found between genders [5] .…”

“…Reported symptoms included headaches, focal neurologic deficits, and seizures. Its hereditary mutation appears to associate with neurofibromatosis type 2 (NF2) [9] . In these cases, the mean age of patients was 37.83 years (range, 9-75 years).…”

“… Ref. Age/sex Clinic Site and growth pattern MRI imaging findings Other imaging findings Surgery Results Appearance Enhancement DTS Peritumoral edema [7] 64/F Transient global amnesia Right tentorium, supratentorial Cystic Heterogeneously enhancing mass - + Subtemporal approach Complete recovery [8] 60/F Long-lasting headaches Left tentorium, supra- and infratentorial Solid Homogeneously enhancing mass + - Suboccipital approach Complete recovery [1] 23/M Intermittent dizziness and difficulty swallowing Right tentorium, infratentorial Cystic and Solid Heterogeneously enhancing mass + - Petrosal craniotomy with retrolabyrynthine bony removal Complete recovery [9] 42/M Paresthesia and weakness of the 4 extremities Left CPA, infratentorial Cystic and Solid Homogeneously enhancing mass + - Retrosigmoid approach Complete recovery [10] 17/F Headaches, intermittent diplopia Left tentorium, supra-and infratentorial Cystic Heterogeneously enhancing mass - - Orbitozygomatic pterional craniotomy Complete recovery, MRI: no residual tumor [6] 22/M Headaches Tentorium, N/A Solid Homogeneously enhancing mass N/A …”