Subpial en bloc resection improves extent of resection in infiltrating gliomas - A propensity matched comparative cohort analysis.

BACKGROUND

Surgery remains the mainstay of glioma therapy and extent of resection is an important prognostic factor. Optimization of surgical outcomes is essential and to this end the technique of resection can potentially play an important role. Based on patterns of glioma growth and extrapolating from other solid cancer surgical principles, a subpial dissection combined with an en-bloc resection (SPER) technique appears to have advantages METHODS: We performed a propensity matched analysis comparing gliomas that were resected using SPER versus a standard piecemeal debulking technique at our centre. Potentially confounding factors (including eloquent location, use of intraoperative imaging, surgeon experience) were adjusted for in the matching of the two cohorts. Outcomes included postoperative morbidity and blinded radiological review documented postoperative ischemia (on diffusion weighted MR imaging - DWI) as well as extent of resection.

RESULTS

In 57 gliomas (23 SPER and 34 standard), the gross total resection (GTR) rates were significantly higher with SPER (91 vs 65%). Postoperative DWI revealed significant ischemia in almost 50% of cases in either group, though many did not have postoperative deficits. Arterial ischemia was higher in the standard surgery group and this was associated with a significantly higher risk (seven times) of resulting in prolonged neurological deficits.

CONCLUSIONS

SPER is a useful technique which increases the GTR rates in gliomas undergoing resection. It is associated with lower incidence of arterial ischemia in the postoperative period and this can result in improved long term functional outcomes.