gms | German Medical Science

Objective: Despite advances in the treatment of gliomas, recurrence remains a matter of time. During surgery for recurrences the surgeon encounters a different environment caused by scar tissue, tissue alterations due to radiation as well as chemotherapy and orientation may be difficult. Five-Aminolevulinic Acid (5-ALA) has been used more frequently over the past years to guide surgery especially in primary gliomas, but only cautiously in recurrent gliomas dreading over resection, insufficient or false-positive fluorescence in pretreated tumors. We evaluated intraoperative fluorescence based on tumor pathology and pretreatment as well as surgical and neurological outcome in patients with recurrent gliomas who underwent fluorescence guided repeat-surgery.

Method: The surgical database was retrospectively searched for patients who underwent fluorescence guided surgery between January 2011 and October 2013 at our institution. Patients with recurrent gliomas were selected for this analysis. Pre- and early postoperative MRI scans were evaluated for degree of surgical resection. Pre- and postoperative neurological status, pathology results and intraoperative fluorescence as well as follow-up status were analyzed.

Results: 47 patients were included. 29 patients (61.7%) were male and 18 female (38.3%). Mean age at surgery was 49 years (range: 26-75years). 11 of 47 tumors (23.4%) failed to fluoresce intraoperatively (WHO °II n =2, WHO° III n=7, WHO °IV n=2) of which eight (72.7%) had been pretreated with radiation and/or chemotherapy. Likewise, 31 of the 36 fluorescing tumors (86.1%) had been pretreated in the same way (p=0.101). 21 tumors (44.6%) were located eloquently. The surgical goal was achieved in 91.5% of cases. 37 (78.7%) patients showed no new neurologic deficits at discharge. No major side effect from 5-ALA were noted. Mean progression free survival was 7.6 months without significant differences between fluorescent and non-fluorescent tumors (p=0.501). 15 patients (31.9%) showed no signs of recurrence at their most recent follow-up. Eight patients were lost to follow-up.

Conclusions: Fluorescence guided surgery in recurrent gliomas is safe and allows for a good surgical as well as neurological outcome in a difficult surgical environment, especially when used in addition to neuronavigation and intraoperative ultrasound to prevent over resection. Adjuvant therapy did not significantly influence fluorescing properties in our series.