Fluorescence-guided surgery and intraoperative photodynamic therapy for the treatment of glioblastoma: a technical case report

Photodynamic therapy (PDT) is a promising intraoperative adjunct in the surgical management of glioblastoma (GBM), targeting infiltrative tumor cells beyond visible resection margins. While 5-aminolevulinic acid (5-ALA) is FDA-approved for fluorescence-guided surgery (FGS) in high-grade gliomas (HGGs), its application in intraoperative PDT is under clinical investigation. We report the first use of a new 5-ALA drug-device combination, Pentalafen®-Heliance® Solution, for both FGS and intraoperative PDT in a GBM patient, as part of a Phase I/II clinical study. A 64-year-old woman presented with progressive headaches, visual field deficits, and cognitive symptoms. MRI revealed a heterogeneously enhancing right temporo-occipital lesion with vasogenic edema and midline shift, consistent with HGG. She was enrolled in a clinical trial evaluating PDT using the Pentalafen®-Heliance® platform. Oral Pentalafen® was administered 4 h prior to surgery. A voice-controlled robotic-assisted exoscope was used for FGS and gross total resection. Intraoperative PDT was then delivered through an inflatable balloon diffuser (Heliance®) positioned in the resection cavity, ensuring homogeneous light distribution. Postoperative MRI confirmed complete resection with no edema or complications. She was discharged on postoperative day 2 and began chemoradiotherapy at week 3. At 3-month follow-up, she remained neurologically stable with no radiographic recurrence. This case demonstrates the technical feasibility and safety of integrating 5-ALA-based intraoperative PDT into standard GBM surgery. The combination of modern visualization platforms, advanced optical delivery, and a next-generation photosensitizer supports further clinical investigation of PDT in neuro-oncologic workflows.