gms | German Medical Science

Objective: The use of 5-aminolevulinic acid (5-ALA) is well established for high grade glioma resections. Meningiomas have also been observed to accumulate fluorescence in response to 5-ALA. Atypical meningiomas tend to recur, despite radiotherapy and are difficult to control surgically, possibly because the true extent of infiltration of adjacent tissue is not distinguishable. We tested the usefulness of 5-ALA for distinguishing residual infiltration in two cases of atypical meningiomas.

Methods: A 47-year-old woman presented with a recurrence of an atypical meningioma (WHO grade II) of the left wing of the sphenoid bone after initial resection two years previously (June 2009). The tumor recurred in November 2011 was operated on using 5-ALA (Gliolan^®). Fuorescence was visualized using a Zeiss Pentero Microscope. The second case was a 21-year-old woman with a recurrence of an parasagital postcentral atypical meningioma (WHO grade II) of the right hemisphere. The initial tumor was resected five years before (April 2006) with consecutive radiotherapy. The tumor recurred 2011 and was resected using 5-ALA.

Results: In both cases macroscopic fluorescence was observed in the gross tumor. However, fluorescence was also found in adjacent dura not clearly distinguished as tumor under white light. Furthermore, small areas of distinct fluorescence were observed within the arachnoid of the adjacent cortex which was removed. Histologically, fluorescence corresponded to tumor infiltration.

Conclusions: 5-ALA (Gliolan^®) derived tumor fluorescence appears to be useful for distinguishing areas of residual infiltration in patients suffering recurrences of atypical meningiomas. Thus, this tool appears to bear potential for enhancing surgery and possibly prognosis in these patients.