Benjamin Brokinkel1, Sabrina Kröger2, Volker Senner3, Astrid Jeibmann3, Uwe Karst2, Walter Stummer4. 1. Department of Neurosurgery, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A1, 48149, Münster, North Rhine-Westphalia, Germany. benjamin.brokinkel@ukmuenster.de. 2. Institute of Inorganic and Analytical Chemistry, University of Münster, Münster, North Rhine-Westphalia, Germany. 3. Institute of Neuropathology, University Hospital, Münster, North Rhine-Westphalia, Germany. 4. Department of Neurosurgery, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A1, 48149, Münster, North Rhine-Westphalia, Germany.
Abstract
BACKGROUND: The advantages of 5-aminolevulinacid (5-ALA)-induced fluorescence-guided surgery in meningiomas are increasingly discussed. In this context, despite detectable tumor tissue in histopathologial analyses, no fluorescence was shown at the dura tail using the standard operating microscope. Thus, 5-ALA metabolism in this surgically important site remains unknown but needs to be elucidated when further evaluating indications of fluorescence-guided surgery in meningiomas. METHOD: We here present the spatially resolved identification of protoporphyrin IX (PpIX) in sphenoid ridge meningioma cryosections from a patient who underwent fluorescence-guided microsurgery using molecular imaging analysis by matrix-assisted laser desorption/ionization tandem mass spectrometry (MALDI-MS/MS). RESULTS: Despite a strong fluorescence of the main tumor, no fluorescence could be detected at the dura tail using the standard operating microscope (blue-light, 405 nm). However, histopathological analyses clearly showed meningioma tissue. Remarkably, MALDI-MS/MS analysis revealed PpIX formation also at the non-fluorescing dura tail. However, no PpIX was detected in the tumor free dura mater. CONCLUSION: MALDI-MS/MS visualized a selective accumulation of PpIX within the tumor tissue including the dura tail. Thus, absence of fluorescence in the dura tail as visualized by the operating microscope is not caused by the lack of PpIX formation.
BACKGROUND: The advantages of 5-aminolevulinacid (5-ALA)-induced fluorescence-guided surgery in meningiomas are increasingly discussed. In this context, despite detectable tumor tissue in histopathologial analyses, no fluorescence was shown at the dura tail using the standard operating microscope. Thus, 5-ALA metabolism in this surgically important site remains unknown but needs to be elucidated when further evaluating indications of fluorescence-guided surgery in meningiomas. METHOD: We here present the spatially resolved identification of protoporphyrin IX (PpIX) in sphenoid ridge meningioma cryosections from a patient who underwent fluorescence-guided microsurgery using molecular imaging analysis by matrix-assisted laser desorption/ionization tandem mass spectrometry (MALDI-MS/MS). RESULTS: Despite a strong fluorescence of the main tumor, no fluorescence could be detected at the dura tail using the standard operating microscope (blue-light, 405 nm). However, histopathological analyses clearly showed meningioma tissue. Remarkably, MALDI-MS/MS analysis revealed PpIX formation also at the non-fluorescing dura tail. However, no PpIX was detected in the tumor free dura mater. CONCLUSION: MALDI-MS/MS visualized a selective accumulation of PpIX within the tumor tissue including the dura tail. Thus, absence of fluorescence in the dura tail as visualized by the operating microscope is not caused by the lack of PpIX formation.
Authors: Sadahiro Kaneko; Benjamin Brokinkel; Eric Suero Molina; Nils Warneke; Markus Holling; Eva Christina Bunk; Katharina Hess; Volker Senner; Werner Paulus; Walter Stummer Journal: Acta Neurochir (Wien) Date: 2020-05-02 Impact factor: 2.216