Chapter 25: Neurooncology
A 50-year-old man is diagnosed with a malignant brain tumor. Which of the following is the most likely cause of malignant brain tumors in this age group?
D. Anaplastic astrocytoma
B. Glioblastomas are the most common malignant brain tumors in adults.
A 9-year-old girl presents with headache and is found by imaging to have a cystic lesion with a protruding nodule in the cerebellum. On biopsy, the tumor is glial in origin, does not have brisk mitotic activity, and has eosinophilic granular droplets. What type of tumor is this?
B. Pilocytic astrocytomas are low-grade (World Health Organization grade I) astrocytomas that are found predominately in the pediatric age group, most commonly occurring around 9 to 10 years of age, and they are most often found in the posterior fossa, specifically in the cerebellum. Patients often present with signs of increased intracranial pressure, such as headache. Histologically, they are sparsely cellular without anaplasia or mitoses. These tumors often contain Rosenthal fibers, which are corkscrew-shaped, eosinophilic intracytoplasmic inclusions, and eosinophilic granular bodies, which are globular aggregates within astrocytic processes.
Which of the following finding is one of the features used to distinguish glioblastoma (GBM) from lower-grade astrocytomas?
C. GBM is a World Health Organization grade IV astrocytoma. Histologically, GBMs have anaplasia and increased mitotic activity and either microvascular proliferation or necrosis.
A patient presents with a tumor in the cerebellopontine angle. On biopsy, the pathology shows Verocay bodies, and the cells stain positive for S100. What type of tumor is this?
E. Schwannomas consist of alternating highly cellular regions (Antoni A regions) that have areas of nuclear palisading (Verocay bodies) and loosely ...