Tumor treating fields (ttf) as maintenance therapy for an oligodendroglioma case and long-term follow-up

Abstract INTRODUCTION Recurrence of low- and high-grade gliomas is observed often after radiation and chemotherapy. Despite continued research on glioma management, there is limited knowledge regarding maintenance treatment after standard care. Tumor Treating Fields as maintenance therapy after radiation and chemotherapy may potentially help prevent recurrence. CASE REPORT In 2011, a 35-year-old male reported headaches to a local ED. A non-enhancing mass was detected on his brain MRI. Observation was advised by his local surgeon. The patient presented with seizures in early 2014, and his brain MRI found the mass developed new enhancement. In late 2014, the patient had multiple seizures, and significant progression of the tumor was discovered. The patient underwent craniotomy and biopsy in the middle cerebral artery distribution area in early 2015. Pathology reported grade II oligodendroglioma; however, the patient only underwent a biopsy, which might have missed the high-grade glioma region. His brain MRI showed a significant enhancing lesion with rapid growth, which was clinically more consistent with grade III oligodendroglioma. Radiation therapy was conducted followed by 6 cycles of PCV chemotherapy throughout 11 months. Post-radiation-chemotherapy brain MRI was stable with a moderate size residual tumor at the right insula region. Following patient wishes, NovoTTF-100A, or Optune, was administered 6 weeks after completion of chemotherapy as maintenance therapy for 2 years to prevent tumor progression. Now, after 3 years being off Optune, the patient is stable without new neurological symptoms or tumor progression. DISCUSSION: Our case highlights the potential effect of Tumor Treating Fields as maintenance therapy after initial radiation and chemotherapy for low- and high-grade oligodendrogliomas. The patient had rapid tumor progression prior to diagnosis and only underwent a biopsy without resection, yet uncommonly, has survived since initial image diagnosis 10 years ago and tissue diagnosis 6 years ago and is fully functional currently.