Concurrent cisplatin therapy and iodine 125 brachytherapy for recurrent malignant brain tumors

Toxicity and safety study of concurrent cisplatin therapy and iodine 125 (125I) brachytherapy.

Iodine 125 brachytherapy has an established role in surgically accessible recurrent tumors of brain. Cisplatin has antitumoral activity against glial neoplasms and has demonstrated sensitization of tumor to radiotherapy.

In 16 patients (age range, 13 to 68 years, median, 47 years), stereotactically placed catheters were afterloaded with 125I sources. A median 50-Gy minimum treatment volume dose was delivered during a 100-hour period along with cisplatin (20 mg/m2 per day for 5 days). Histologic diagnoses included glioblastoma multiforme (n = 11), anaplastic astrocytoma (n = 3), ependymoma (n = 1), and anaplastic oligodendroglioma (n = 1). Tumor volumes ranged from 7.0 to 73 cm3 (median, 25 cm3).

Early complications included headache (n = 7), transient exacerbations of preexisting neurologic deficits (n = 5), seizures (n = 3), and nausea/vomiting (n = 3). Late complications included steroid dependency (n = 10), progressive dementia in the absence of recurrent tumor (n = 1), and radiation-induced necrosis (n = 9) requiring reoperation (n = 9). Fifteen of 16 patients were assessable, with a median follow-up time of 9.5 months. Brachytherapy was discontinued in one patient owing to an acute subdural hematoma. A partial response was seen in five patients, disease remained stable in seven patients, and disease progressed in three patients.

We conclude that 125I brachytherapy with concurrent cisplatin therapy is associated with an acceptable level of toxic effects and warrants further investigation.