Thirteen patients with low grade astrocytomas were treated with alkylating agent or platinum-based chemotherapy regimens. Eleven of these patients received chemotherapy as their initial postoperative treatment modality, and 2 others as treatment for progressive disease postradiation therapy. Responses were objectively determined using CT or MRI. One patient had a complete response (CR), 6 had partial responses (PR), and 3 others had stable disease (SD) as their best response. Clinical responses paralleled those determined objectively. Chemotherapy was well tolerated with the exception of ototoxicity in 4 patients treated with cisplatin. Despite good initial responses, 5 of 6 patients who received no further treatment postchemotherapy (4 PR, 1 SD) developed progressive disease 5-13 months after completing chemotherapy. The remaining 4 patients with objective responses or stable disease (1 CR, 2 PR, 1 SD), all received further postchemotherapy treatment with radiation therapy or surgery, and have not demonstrated disease progression. Our experience suggests that alkylator or platinum-based chemotherapy can successfully delay the growth of these locally infiltrative neoplasms, and should be considered in their primary management. Despite the experience of others, further therapy appears necessary in patients with residual CT or MRI abnormalities postchemotherapy.