Only The Best Of The Neurologists Can Beat This Quiz About Brain Tumors

The correct answer is lung, breast, melanoma. These three primary malignancies are known to be the most common causes of metastatic brain tumors. Lung cancer often spreads to the brain through the bloodstream, while breast cancer can metastasize to the brain through lymphatic channels or blood vessels. Melanoma, a type of skin cancer, is also known for its tendency to spread to the brain. These three primary malignancies have a higher likelihood of metastasizing to the brain compared to the other options listed.

The correct answer is pituitary gland and stalk. A bi-temporal hemianopsia is characterized by loss of vision in the outer half of the visual field of both eyes. This is typically caused by a lesion in the optic chiasm, which is located near the pituitary gland and stalk. Tumors in this region can compress the optic chiasm, leading to visual field defects. Therefore, based on the symptoms described, the most likely location of the tumor is near the pituitary gland and stalk.

The symptoms of unilateral tinnitus, unilateral hearing loss, facial weakness, and loss of corneal reflex on the same side suggest a lesion in the cerebellopontine angle. The cerebellopontine angle is located between the cerebellum and the pons, and it contains important structures such as the facial nerve, vestibulocochlear nerve, and the trigeminal nerve. A lesion in this area can result in compression or damage to these nerves, leading to the observed symptoms. The other options listed do not correspond to the anatomical location that would explain the patient's symptoms.

The presence of a tumor near the cerebellopontine angle arising from the VIIIth nerve suggests a diagnosis of Schwannoma. Schwannomas are benign tumors that arise from Schwann cells, which are responsible for myelinating peripheral nerves. The histological findings of benign spindle-shaped cells with Antoni A and Antoni B patterns are consistent with Schwannoma. Ependymoma, Astrocytoma, Medulloblastoma, and Glioblastoma multiforme are not typically associated with the VIIIth nerve and do not exhibit the specific histological features described.

The most likely cause of the patient's pupillary findings is increased edema leading to uncal herniation and compression of CNIII. The patient's MRI shows a tumor involving the left fronto-temporal lobes with a large amount of surrounding edema. Increased edema can cause herniation, specifically uncal herniation, which occurs when the uncus of the temporal lobe is displaced medially and compresses the third cranial nerve (CNIII). CNIII compression can lead to pupillary findings such as a dilated and unreactive pupil, which is consistent with the patient's symptoms.

The correct answer is well circumscribed nodule, whorls of spindle-shaped cells, and psammoma bodies. Meningiomas are typically characterized by a well-circumscribed nodule, meaning they have a clear boundary separating them from surrounding tissue. They also exhibit whorls of spindle-shaped cells, which refers to the arrangement of cells in a swirling pattern. Psammoma bodies, which are concentrically calcified structures, are often present in meningiomas. These pathomorphologic criteria help in the diagnosis of meningioma.

The criteria used for the diagnosis of oligodendroglioma include a well circumscribed nodule, the presence of "fried-egg" cells, and a chicken-wire capillary pattern. These features are characteristic of oligodendroglioma and help distinguish it from other types of brain tumors. A well circumscribed nodule refers to a distinct and clearly demarcated mass within the brain. "Fried-egg" cells are oligodendroglial cells with round nuclei and clear cytoplasm, resembling a fried egg. The chicken-wire capillary pattern refers to the network of blood vessels that appear like a chicken wire mesh. These criteria together help in the accurate diagnosis of oligodendroglioma.

The attending resident states that the tumor is the most common kind of intracranial tumor with a poor prognosis. This suggests that the tumor belongs to a specific type that is known for being common and having a poor prognosis. The correct answer, astrocytomas, fits this description as they are the most common type of brain tumor and are known for having a poor prognosis. Schwannomas, oligodendrogliomas, meningiomas, and ependymomas are not typically associated with being the most common type of intracranial tumor or having a poor prognosis.

The correct answer is secondary polycythemia. This is because the patient's symptoms and physical examination findings are consistent with von Hippel-Lindau (VHL) disease, which is characterized by the development of multiple tumors and cysts in various organs, including the brain, retina, kidneys, and adrenal glands. One of the manifestations of VHL disease is the development of hemangioblastomas in the cerebellum and retina, which can lead to gait disturbance and blurred vision. Additionally, VHL disease can cause the production of excess erythropoietin, leading to secondary polycythemia.