Initial surgical resection and long time to occurrence from initial diagnosis are independent prognostic factors in resected recurrent IDH wild-type glioblastoma.

Objective: IDH wild-type glioblastoma is the most common and aggressive primary brain cancer in adults. At tumor recurrence, treatment decision-making is not standardized; several options include second surgery, reirradiation, and a second line of chemotherapy. In this retrospective monocentric study conducted at the era of WHO 2016 classification, we investigated IDH wild-type glioblastoma patients below the age of 70 to see (i) the clinical benefit of second surgery at recurrence and (ii) the prognostic factors in resected recurrent glioblastoma patients.

Methods: 229 newly diagnosed IDH wild-type glioblastoma patients below the age of 70 treated with the standard of care (SOC) were enrolled in the current study and stratified into two subgroups according to treatment at recurrence: re-resection and no re-resection.

Results: All experienced tumor recurrence with a median progression-free survival of 11 months. 25 % of patients were reoperated. Patients reoperated at recurrence had longer post-progression median overall survival compared to their non-reoperated counterparts (14 versus 9 months, p < .05). Initial surgical resection and a long time from the initial diagnosis to the first recurrence were independent prognostic factors for good outcomes in resected recurrent IDH-wild-type glioblastoma patients; however, tumor size before and after surgery did not impact post-surgical survival.

Conclusion: Our study supports surgical resection at recurrence as therapeutic in IDH wild-type glioblastoma patients aged below 70 and in good clinical condition regardless of preoperative tumor size, particularly in patients who experienced a longer time before first recurrence and surgery at initial diagnosis. Further prospective and larger studies are warranted to validate our findings.