Proliferative Potential of Sporadic and Neurofibromatosis 2-Associated Schwannomas as Studied by MIB-1 (Ki-67) and PCNA Labeling

The Molecular Biology of Vestibular Schwannomas: Dissecting the Pathogenic Process at the Molecular Level

“…However, before this can be stated as fact, the cellular mechanism leading to the development of cystic schwannomas needs to be better understood. Lastly, NF2-associated schwannomas have been shown to have an increased proliferation index by Ki-67 and proliferating cell nuclear antigen immunostaining when compared with unilateral solid schwannomas (98).…”

Mild familial neurofibromatosis 2 associates with expression of merlin with altered COOH-terminus

“…The cell proliferation indices of seven schwannomas from five family members were analyzed using two markers, MIB-1 (n ϭ 7) and PCNA-LI (n ϭ 6), and compared with 31 unrelated NF2-associated schwannomas as described earlier. 27 Statistical analysis was performed using the Mann-Whitney U test.…”

Management strategies for bilateral vestibular schwannomas

“…2,4,31 However, a comparison of the anatomical preservation rates of facial nerves of bilateral versus unilateral VS shows significant differences in the present study (43.8% vs. 80.2% respectively). This may be because schwannomas in patients with NF2 have multifocal origins from the VIIth/VIIIth nerve complex so that the facial nerve dissection is difficult in comparison to sporadic unilateral VS. 2,26,27,32 Moreover, the plane of cleavage between the tumor and the VIIth nerve is not as good in patients with NF2 when compared to non-NF2 patients. 28 Fifteen of our patients had large or giant VS, which also greatly increased the surgical morbidity.…”

“…Therefore, hydrocephalus, symptoms of raised intracranial pressure and neurological deficits develop earlier in NF2 patients as the brain does not have sufficient time to compensate. [26][27][28] Thus, papilledema was present in 81.3% of patients with bilateral VS compared to 60.1% with unilateral VS; secondary optic atrophy leading to complete blindness was present in 37.5% of patients with bilateral VS in contrast to 11.8% of patients with unilateral VS. The incidence of lower cranial nerve involvement was also significantly higher in bilateral VS than in unilateral VS.…”