The role of Gliadel wafers in the treatment of high-grade gliomas

Abstract

Glioblastoma multiforme (GBM) is the most aggressive brain tumor. Standard treatment includes surgery, radiation and chemotherapy. Prognosis is dismal with an average survival of approximately 1 year. Gliadel wafers are one treatment option, working as a source for local chemotherapy delivery. Their use is controversial with questionable survival benefit and potential side effects. We reviewed the literature in an effort to clarify their role in the treatment of high-grade gliomas. A systematic PubMed search was performed using the keywords ‘Gliadel’, ‘carmustine’ or ‘BCNU wafers’ in newly diagnosed high-grade glioma patients. Treatment regimen, and median survival were analyzed. Adverse event ratio was calculated by computing the number of adverse events in a study per patient receiving carmustine wafers. Nineteen studies with 795 patients were included in our review. Survival was 8.7–22.6 months with a mean overall survival (OS) of 16.2 months (control survival is approximately 14 months with surgery and adjuvant chemoradiotherapy). Adverse event ratio using Gliadel wafersin control group. Complication rate was 42.7%. Gliadel wafers may marginally increase survival and local control in newly diagnosed GBM patients but are associated with a high complication rate; therefore, we do not recommend using Gliadel wafers in patients with GBM. Further research may be warranted once a safer alternative to Gliadel wafers has been introduced.

Keywords::

• carmustine
• chemotherapy
• gliadel wafers
• glioblastoma multiforme

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• • Placement of carmustine wafers for high grade gliomas remains controversial.

• • Wafer placement may confer a slight survival advantage for patients (<6 weeks) with high grade glioma compared to control.

• • Carmustine wafer placement is associated with significant toxicities in approximately 40% of patients including myelosurpression, intracranial infections, worsening of neurological deficits, or mass effect.

• • Carmustine wafers may work in conjunction with oral temozolomide, but the risk of hematological toxicity is markedly increased when used in conjunct.

• • Treatment response and malignant cerebral edema/mass effect may be hard to distinguish after wafer placement.

• • Newer safer drug delivery systems including convection-enhanced delivery and personalized drug therapy are necessary to provide a safer efficacious alternative to wafer placement.