The effects of PDT in primary malignant brain tumours could be improved by intraoperative radiotherapy

Introduction: GBM has a poor survival despite surgery and chemoradiotherapy. Cytoreduction and PDT have postulated to afford better local GBM-control. However, the interaction of PDT with newer novel therapies had not been fully investigated. This study reviewed the impact of PDT in conjunction with intraoperative radiotherapy.

Methods: Case note review of prospectively collected data of GBMs treated surgically by the senior author (SE). Patients received standard therapy (ST), ST + PDT or ST + PDT + IORT. ST involved maximum safe resection, PDT involved intracavity 100 J/cm(2) 630 nm laser and IORT involved intracavity 10-15 Gys using the PRS400 (R). Patients were followed up clinically and radiologically till death.

Results: There were 73 patients included in this analysis (42 males). The average age was 59 years. Thirty received PDT and 43 did not. The mean survival of PDT-patients was significantly longer than those had ST alone (62.9 weeks vs. 20.6 weeks) (p=0.001). Patients <65 year of age survived longer than those >= 65 year (p=0.033). IORT on its own did not make a significant difference to survival (p=0.111). However the average survival for patients who received PDT + IORT was substantially higher than those who received PDT alone (79 weeks vs. 39.7 weeks). Using a Cox regression covariant analysis, demonstrated that PDT was the only therapy to make a statistically significant difference to survival (p=0.018).

Conclusions: PDT in high grade glioma was statistically significant therapeutic modality and its effects were further improved by IORT. (c) 2011 Elsevier B.V. All rights reserved.