Safety and efficacy of Gliadel wafers for newly diagnosed and recurrent glioblastoma

Combining Gliadel wafers and radiochemotherapy with TMZ may carry the risk of increased adverse events (AE). We analyzed the efficacy and safety in patients with glioblastoma who underwent multimodal treatment with implantation of Gliadel wafers.

One hundred sixty-five consecutive patients with newly diagnosed (77 patients) or recurrent (88 patients) glioblastoma were studied. Forty-seven patients underwent surgery + Gliadel. The impact of age (≥65 vs. <65), resection extent (gross total vs. partial), use of Gliadel and adjuvant treatment (TMZ vs. other schemes/no adjuvant therapy) on overall survival (OS, for patients with newly diagnosed glioblastoma) and on recurrence-survival (for patients with recurrent glioblastoma) was analyzed with Cox regression. The impact of age, history (newly diagnosed vs. recurrent glioblastoma), number of Gliadel wafers implanted (0 vs. <8 vs. 8), resection extent (gross-total vs. partial) and adjuvant treatment (TMZ vs. other schemes/no adjuvant therapy) on the occurrence of AE and on the occurrence of implantation site-related AE (ISAE) was analyzed with the logistic regression model. Significance was set at p < 0.05.

Multivariate analysis showed the only factor associated with longer survival, both for newly diagnosed and for recurrent GBM, was resection extent. Both patients with a higher number of wafers implanted and patients with recurrent tumors were significantly at risk for AE and ISAE. Patients with eight Gliadel wafers implanted had a 3-fold increased risk of AE and a 5.6-fold increased risk of ISAE, and patients with recurrent tumor had a 2.8-fold increased risk of AE and a 9.3-fold increased risk of ISAE.

Adding Gliadel to standard treatment did not significantly improve the outcome. The toxicity after Gliadel use was significantly higher, both for patients with newly diagnosed and patients with recurrent glioblastoma.