Natural history of petroclival meningiomas

OBJECTIVE: For evaluation of the natural history of petroclival meningiomas, a cooperative retrospective study of 21 conservatively treated patients is reported. METHODS: All patients had petroclival meningiomas that were observed for at least 4 years, with regular clinical and radiological control examinations. The follow-up periods ranged from 48 to 120 months (mean, 82 mo; median, 85 mo). Functional evaluations were performed by using the Karnofsky index. Individual growth curves and rates were defined. RESULTS: Age and sex distributions and presenting symptoms were comparable to those of other studies. During follow-up monitoring, radiological tumor growth was observed in 76% of the cases. With 63% of the growing tumors, there was functional deterioration. We performed statistical analyses of demographic features, radiological findings, and functional deterioration. Severe functional deterioration was observed to be statistically significantly associated with infratentorial growth and increased growth rates. A change in the growth pattern often preceded functional deterioration. CONCLUSION: This study provides a better understanding of the natural course of petroclival meningiomas. The growth patterns of these tumors are unpredictable and variable. The exact factors influencing growth remain unclear. This study can contribute to the optimization of individual management of these tumors.