Radiolabeled cetuximab plus whole-brain irradiation (WBI) for the treatment of brain metastases from non-small cell lung cancer (NSCLC).

Background and Purpose: The addition of systemic drugs to whole-brain irradiation has not improved the survival of patients with multiple brain metastases, most likely because the agents did not readily cross the blood-brain barrier (BBB). Radiolabeling of cetuximab was performed to investigate whether this antibody crosses the BBB.
Case Report: A patient with multiple brain lesions from non-small cell lung cancer was investigated. The largest metastasis (40 x 33 x 27 mm) was selected the reference lesion. On day 1, 200 mg/m(2) cetuximab (0.25% hot and 99.75% cold antibody) were given. On day 3, 200 mg/m(2) cetuximab (cold antibody) were given. Weekly doses of 250 mg/m(2) cetuximab were administered for 3 months.
Results: The reference lesion showed enhancement of radiolabeled cetuximab ((123)I-Erbi) on scintigraphy; (123)I-Erbi crossed the BBB and accumulated in the lesion. The reference lesion measured 31 x 22 x 21 mm at 4 months. Enhancement of contrast medium was less pronounced.
Conclusion: This is the first demonstration of cetuximab crossing the BBB and accumulating in brain metastasis.