Surgery for Recurrent Glioblastoma

Background

Glioblastoma is a malignant, locally invasive brain tumor whose prognosis remains grim despite various intense treatment modalities. In the past, radical surgery was met with skepticism due to the aggressive infiltrative character of the tumor. However, an increasing number of retrospective studies over the last decade suggest a survival benefit for surgery. A recent post-hoc analysis of a randomized controlled trial on the use of the surgical adjunct 5-ALA reported a prolonged overall survival from 11.9 to 16.7 months (evidence level 2a) after more extensive resection. Thus, maximal safe resection has become a mainstay of treatment for newly diagnosed glioblastoma, followed by adjuvant radio-chemotherapy.

Glioblastoma almost invariably recurs after a median of 6.9 months, leaving but few options for further treatment. Recurrence of glioblastoma after surgery and concomitant adjuvant therapy represents an additional therapeutic challenge and may be treated with second-line pharmacotherapy. In addition, a second surgery may also be considered in highly selected patients.

The rationale for surgery - maximum safe resection - is to prolong survival through reduction of tumor load, and, maybe due to an increased efficacy of adjuvant treatment. However, surgery carries risks of complications, that may result in a decreased functional and survival outcome. The crucial question therefore is whether, to what extent, and at what costs in terms of neurological risks a second resection prolongs survival.

Objective

The primary objective of this randomized trial is to compare survival outcome after surgery followed by adjuvant second-line therapy to no surgery followed by second-line therapy in recurrent glioblastoma. An auxiliary objective to primary objective is to compare the survival outcomes of operated patients to control in the subgroups stratified by extent of resection: incomplete resection (non-CRET) vs complete resection (CRET).

Secondary objectives are: assessment of recruitment for all screened patients, comparison of progression-free survival between treatment arms, evaluation of crossover and comparison of patient quality of life between treatment arms.

Safety objectives are: to assess neurological deficits, local infections and morbidity associated to surgery and hospital stay after surgery and during follow-up.

Methods

All patients (≥18 years) with a radiological suspicion of first recurrence of glioblastoma are screened for this trial. Patients eligible for study participation are informed on the treatment options for recurrent glioblastoma (surgery followed by adjuvant second-line therapy, second-line therapy, or palliative therapy alone) by the center investigators. Patients randomized to the control group will receive second-line therapy according to local guidelines. Patients randomized to the interventional group will receive a craniotomy and resection of the tumor followed by adjuvant second-line therapy. Outcome will be measured at 3 months intervals.

Recruitment rate and reason for non-inclusion will be monitored.

• Recruitment rate for all screened patients [Time frame: Screening and inclusion]
• Progression-free survival [Time frame: From the date of inclusion until the date of objective progression or the date of patient's death, whichever occurs first, assessed up to 5.7 years]
• Morbidity of surgery [Time frame: Every 3 months up to 2 years or until death, assessed up to 5.7 years]
• Total number of days spent at home after recurrence [Time frame: From the date of inclusion until death/end of study, assessed up to 5.7 years]
• Total number of days spent outside home after recurrence [Time frame: From the date of inclusion until death/end of study, assessed up to 5.7 years]