Tumor regression following autologous tumor lysate-loaded dendritic cell vaccination immunotherapy: illustrative case.

backgroundDespite years of research, the standard of care (SOC) treatment for grade 4 glioma has remained virtually unchanged for the last 2 decades. Autologous tumor lysate-loaded dendritic cell vaccination (DCVax-L), a novel immunotherapy, has demonstrated a significant survival benefit in a phase 3 trial. OBSERVATIONS: A 34-year-old male presented with episodes of lightheadedness and was subsequently diagnosed with a large fronto-insulo-temporal tumor, likely to be high grade. He underwent an asleep craniotomy for debulking, with a residual tumor noted in the frontal lobe and amygdala. Tumor histopathology was reported as isocitrate dehydrogenase (IDH) mutant methylated grade 4 astrocytoma. He received SOC treatment, alongside a course of DCVax-L. Surveillance imaging showed cystic transformation followed by a reduction in size of the residual tumor in the frontal lobe; the residual in the amygdala had regressed entirely. The patient remained clinically well and had returned to his preoperative functionality. LESSONS: The authors report a patient with grade 4 astrocytoma who received DCVax-L treatment in addition to SOC adjuvant therapy. The pattern and extent of tumor regression are highly unusual and atypical for what is seen or expected with adjuvant SOC treatment alone. The addition of DCVax-L to SOC opens new avenues in the management of this difficult disease. https://thejns.org/doi/10.3171/CASE24112.