Abstract
PurposeCarmustine wafers can be implanted in the surgical bed of high-grade gliomas, which can induce surgical bed cyst formation, leading to clinically relevant mass effect.MethodsAn observational retrospective monocentric study was conducted including 122 consecutive adult patients with a newly diagnosed supratentorial glioblastoma who underwent a surgical resection with Carmustine wafer implantation as first line treatment (2005–2018).FindingsTwenty-two patients (18.0%) developed a postoperative contrast-enhancing cyst within the surgical bed: 16 uninfected cysts and six bacterial abscesses. All patients with an uninfected surgical bed cyst were managed conservatively, all resolved on imaging follow-up, and no patient stopped the radiochemotherapy. Independent risk factors of formation of a postoperative uninfected surgical bed cyst were age ≥ 60 years (p = 0.019), number of Carmustine wafers implanted ≥ 8 (p = 0.040), and partial resection (p = 0.025). Compared to uninfected surgical bed cysts, the occurrence of a postoperative bacterial abscess requiring surgical management was associated more frequently with a shorter time to diagnosis from surgery (p = 0.009), new neurological deficit (p < 0.001), fever (p < 0.001), residual air in the cyst (p = 0.018), a cyst diameter greater than that of the initial tumor (p = 0.027), and increased mass effect and brain edema compared to early postoperative MRI (p = 0.024). Contrast enhancement (p = 0.473) and diffusion signal abnormalities (p = 0.471) did not differ between postoperative bacterial abscesses and uninfected surgical bed cysts.ConclusionsClinical and imaging findings help discriminate between uninfected surgical bed cysts and bacterial abscesses following Carmustine wafer implantation. Surgical bed cysts can be managed conservatively. Individual risk factors will help tailor their steroid therapy and imaging follow-up.
Prognostic effects of O6-Methylguanine DNA methyltransferase promoter hypermethylation in high-grade glioma patients with carmustine wafer implants
