CHEMOTHERAPY FOR PROGRESSIVE PILOCYTIC ASTROCYTOMAS IN THE CHIASMO-HYPOTHALAMIC REGIONS

Over the past 25 years, we have treated 17 patients with chiasmo-hypot halamic astrocytomas. Before 1988, the initial treatments consisted of surgery and/or radiotherapy, while since 1989, 4 children (1 male, 3 females, aged 3-8 years) were treated primarily with chemotherapy. Non e of them was associated with neurofibromatosis. After a biopsy of the tumor, the intraveneous administration of ranimustine (MCNU; 30-86 mg /m(2)) and/or nimustine (ACNU; 30.3-64.1 mg/m(2)) was given without ra diation therapy. Chemotherapy was usually given as an out-patient, wit h a total of 5-13 courses. The total doses of MCNU and ACNU administer ed ranged from 150 to 570 mg and from 64.8 mg to 100 mg, respectively. After chemotherapy 2 patients showed clinical improvement and tumor r egression on neuro-imaging, while one patient showed clinical improvem ent and tumor size stabilization on neuro-imaging. The remaining one c hild, however, showed a clinical worsening and tumor progression on ne uro-imaging studies. He was thus treated with a second chemotherapy re gimen with carboplatin and etoposide, which brought about tumor regres sion. The acute and subacute toxicity of chemotherapy was mild. All pa tients are now leading almost normal lives with a median of 43 months after diagnosis. Although a longer and more careful clinical observati on is required, the authors conclude that chemotherapy with MCNU and/o r ACNU may benefit patients with unresectable pilocytic astrocytoma re quiring treatment. The advantages of this therapy include its mild sid e effects and the lack of any hospitalization in most patients. It may also delay the need for radiation therapy, which can have a deleterio us effect on the young developing brain.