The use of adjuvant immunotherapy for the treatment of primary malignant brain tumors dates to studies performed in the 1960's and 1970's using non-specific immune stimulators. Although the theoretical designs have remained similar, recent advances in molecular biotechnology have produced a new group of recombinant cytokines, spawning a new generation of immunotherapy-based clinical trials. In contrast to other published Phase I/II studies, we have had highly encouraging preliminary results using lymphokine-activated killer (LAK) cells and recombinant human Interleukin-2 (rIL-2; Cetus, Emeryville, CA), when the patients' use of corticosteroids could be restricted while on study. Patients with recurrent grade 3/3 glioma received multiple cycles of autologous LAK cells and rIL-2, post-operatively, via an Ommaya reservoir implanted into the tumor cavity following re-operation. The overall median survival for 13 patients with grade 3/3 glioma has not yet been reached at 55 weeks following second surgery, [mean +/- SEM, 64.7 +/- 10.5 weeks], with 5 patients still alive. Three patients have had partial responses (PR) demonstrated by CT scanning. In addition, one patient with grade 2/3 glioma has had a complete response (CR), with the disappearance of all residual CT-documented enhancement and mass effect.