Carmustine Wafers (Gliadel) in Brain Metastases: Revisiting an Old Concept With New Insights

Brain metastases (mets) are the most common type of brain tumor and a major cause of mortality in cancer patients. Better control of brain mets is therefore crucial for improving both quality of life and survival. Carmustine wafers (BCNU, Gliadel) have been shown to improve local control and survival in patients with high-grade gliomas. In this study, we reviewed patients at our institute who received BCNU wafers for brain mets over the past seven years to assess potential benefits in local disease control and overall survival.

This was a single-institute retrospective observational study evaluating the use of carmustine (BCNU) wafers following resection of brain mets. Data were retrieved from the pathology department records between 2018 and 2025, including 73 patients. Patients were divided into two groups: Arm A, who underwent brain tumor resection without BCNU implantation, and Arm B, who underwent resection with BCNU wafer placement. Statistical analysis was performed, and a two-tailed p-value < 0.05 was considered statistically significant.

There was an equal proportion of male and female patients, with comparable age distribution in both arms. The most common primary cancer was lung cancer, and the frontal lobe was the most frequent site of mets. Progression-free survival (PFS) and overall survival (OS) were assessed. PFS was significantly higher in patients who received BCNU wafers (p = 0.008), while OS also favored BCNU use but did not reach statistical significance. Survival outcomes were not influenced by the type of primary cancer or the site of brain mets. PFS was significantly better in patients aged ≤ 65 years who underwent resection (p = 0.01).

The use of BCNU wafers in brain mets has been reported in only a few studies, mostly with small sample sizes and published before 2015. In our study, we evaluated their role in the modern era of chemotherapy and targeted therapies, many of which have improved penetration across the blood-brain barrier. PFS was 95% at six months, one year, two years, and five years in patients treated with BCNU wafers, compared to 71% at six months and 68% at one and two years in the non-BCNU group. This strongly favors BCNU use after brain met resection. Our study demonstrated higher PFS rates than previously reported, which may reflect the synergistic effect of newer systemic treatment options. While BCNU is expected to improve local disease control rather than OS, we observed an OS advantage in the BCNU group during the first six months, although this did not reach statistical significance. The impact of age on survival was evident, with younger patients faring better, but this effect was independent of BCNU use. Further studies are warranted to explore this parameter in more detail.

Brain mets are most common in lung cancer, and the frontal lobe is the most frequent location. The use of BCNU after resection of brain mets improves PFS across primary cancer types, particularly lung cancer. OS also favored BCNU use, though not significantly. Younger patients (≤65 years) had better survival following surgery for brain mets, with or without BCNU use.