Therapeutic strategy and long-term outcome of meningiomas located in the posterior cranial fossa.

The clinical and surgical findings of 41 consecutive cases of posterior cranial fossa meningiomas operated on between January 1987 and December 2011 at Saitama Medical Center/Saitama Medical University were reviewed. The 31 female and 10 male patients were aged from 19 to 74 years (mean 54 years). The tumors were located in the petroclival (N=15), craniovertebral junction (N=6), lateral tentorial (N=12), and cerebellopontine angle (N=8) regions. Mean tumor equivalent diameter was 4.3 cm (range 2-9 cm). Head pain (46.3%) and gait disturbance (26.8%) were the most common presenting symptoms, and cranial neuropathies were the most common neurological signs on admission. Mean preoperative performance status (Karnofsky scale) was 83% (range 40-100%). Surgical approaches to these tumors included presigmoidal transpetrosal, retrosigmoidal, transcondylar, and combined approaches. In 4 cases, a staged procedure was performed. Gross total resection was achieved in 85.4% of patients, and subtotal/partial resection in 12.2%. Surgical mortality was 2.4% and complications were encountered in 11 patients (26.8%) including temporary neurological deficits in 4 patients. The mean follow-up period was 8.2 years, ranging from 1 to 24 years, and the mean performance status of patients at 12 months after the last surgery was 92% (range 0-100%). Recurrence or progression of disease was found in 9.8% of cases. Postoperative adjuvant therapy was performed in 6 cases. My experience suggests that although posterior cranial fossa meningiomas represent a continuing challenge for contemporary neurosurgeons, such tumors may be completely or subtotally removed with low rate of mortality and acceptable morbidity, allowing most of these patients to achieve good outcome in long-term follow up.