P06.20.b long-term clinical results of 493 cases of newly diagnosed glioblastoma and survival benefit by combination with pdt and aftv, aiming to establish new standard treatment

Abstract BACKGROUND Glioblastoma has the worst prognosis of brain tumors. Evidence for improving prognosis by maximal tumor removal is being established, and in recent years, new treatments such as photodynamic therapy (PDT, 2014 in Japan), and TTF therapy (2018) have been approved, the treatment results are improving. In principle, our facility performs maximum tumor removal using intraoperative MRI (iMRI) follow by the standard chemoradiation. Intraoperative PDT and autologous tumor vaccine (AFTV) will be given to desired patients. We retrospectively analyzed the long-term clinical results of the patients with newly diagnosed glioblastoma who underwent surgical treatment at our facility, and the treatment results by era and treatment method. MATERIAL AND METHODS The clinical features, extent of removal (EOR), OS and PFS of the adult patients with newly diagnosed glioblastoma treated from 2001 to 2021 were analyzed retrospectively. Clinical results of those patients who received PDT and AFTV treatment was also investigated. RESULTS The number of cases was 493, median age 58 years (18-85 years), 293 males, 200 females. The median and average EOR of contrast-enhanced lesions were 98% and 96.6%, respectively. The median PFS and OS of all cases (including biopsy) were 9.4 months and 22.7 months, respectively. When the cases were analyzed separately for 2001-2006 (before TMZ), 2007-2010, 2011-2015, and 2016-2021, the median OS for each age group was 12.9 months, 22.9 months, 23 months, and 31.1 months. The treatment results improved with age (p <0.0001). In particular, the median OS of 23 cases treated with PDT and AFTV was 63.1 months. The efficacy of AFTV for newly diagnosed glioblastoma is currently being verified in a multicenter Physician-led clinical trial. CONCLUSION The treatment results for glioblastoma have improved over the years. The combination of maximal tumor removal using iMRI, PDT and AFTV may aim for a 5-year survival rate of 50%.