Neoplasms Flashcards
A 65-year-old right-handed woman began having neurological problems about 1 week ago. She began experiencing nausea, vomiting, and numbness in the left hand and left foot. Today she had a generalized convulsion, and since then she has had a throbbing headache that is worse when she bends forward. On examination, the only deficits she has are loss of double simultaneous tactile stimulation and left lower facial droop when smiling. MRI reveals a lesion suggestive of a primary brain tumor.
- The most common sources of primary brain tumors are
a. Glial cells
b. Neurons
c. Meningeal cells
d. Lymphocytes
e. Endothelial cells
A
(Bradley, p 1266.) Between 2 and 5% of all tumors occurring in the general population are primary CNS tumors. In adults, the most common primary brain tumor is the astrocytoma. In children, brain tumors are more likely to arise in the posterior fossa. Even in childhood, glial cell tumors, such as the cerebellar astrocytoma and the optic glioma, are common.
A 65-year-old right-handed woman began having neurological problems about 1 week ago. She began experiencing nausea, vomiting, and numbness in the left hand and left foot. Today she had a generalized convulsion, and since then she has had a throbbing headache that is worse when she bends forward. On examination, the only deficits she has are loss of double simultaneous tactile stimulation and left lower facial droop when smiling. MRI reveals a lesion suggestive of a primary brain tumor.
- The most common type of primary brain tumor is
a. Meningioma
b. Astrocytoma
c. Lymphosarcoma
d. Oligodendroglioma
e. Medulloblastoma
B
(Bradley, p 1266.) The most common primary brain tumors are malignant astrocytomas. These are classified as grade 3 or 4. Grade 4 astrocytoma is more commonly called glioblastoma multiforme. It is malignant in the very conventional sense that it invades adjacent tissue. This type of glial tumor is usually seen in adults; men are more susceptible than women.
- Most brain tumors in children are
a. Metastatic lesions from outside the central nervous system (CNS)
b. Oligodendrogliomas
c. Glioblastomas multiforme
d. Meningiomas
e. Infratentorial
E
(Bradley, p 1276.) The posterior fossa is the usual location for brain tumors in children. Medulloblastomas, ependymomas, and cerebellar (or brainstem) gliomas account for most of the tumors that occur before puberty. Other common tumors developing intracranially in children include optic gliomas and metastatic leukemias.
- The incidence of primary brain tumors in children - about 1 to 5 per 100,000 per year - is mainly accounted for by
a. Meningiomas and neurofibromas
b. Astrocytomas and medulloblastomas
c. Melanomas and choriocarcinomas
d. Gliomas and adenomas
e. Colloid cysts of the third ventricle
B
(Rowland, p 297.) Meningiomas may occur in childhood but are more likely to appear and become symptomatic during adult life. Neurofibromas are not primary brain tumors, although schwannoma of the eighth cranial nerve is sometimes incorrectly referred to as an acoustic neurofibroma rather than an acoustic schwannoma. Colloid cysts of the third ventricle are not necessarily neoplastic, although most are assumed to have started as neoplasms rather than as developmental anomalies. Glioma is a broad category that includes the astrocytoma. Adenomas, such as pituitary adenomas, do develop in children, but much less commonly than either astrocytomas or medulloblastomas. Central nervous system tumors account for a large proportion of the tumors seen in childhood. In fact, they are second in frequency only to childhood leukemias and account for 15 to 20% of childhood tumors.
- A 72-year-old woman has a head CT performed because of headaches. It is significant for a left hemisphere mass with an overlying hyperostosis of the skull. She most likely has which of the following?
a. Meningioma
b. Pituitary adenoma
c. Astrocytoma
d. Schwannoma
e. Hemangioblastoma
A
(Rowland, p 306.) Hyperostosis is thickening of the bone and is much less commonly induced by tumors in or about the brain than is thinning of the bone. Thinning occurs especially with pituitary adenomas, which may cause erosions in the floor of the sella turcica as an early feature. Calcifications may develop in schwannomas or astrocytomas, but both of these tumor types will usually cause bony erosions where they impinge on the skull. Calcifications may develop in many primary or metastatic brain tumors, but calcification sufficient to be readily seen on a skull x-ray suggests an astrocytoma, meningioma, oligodendroglioma, or metastatic tumor. Calcification can be visualized on CT scan in about 17% of medulloblastomas. With meningiomas, hyperostosis may develop in the bone adjacent to the tumor even if there is no infiltration of the bone by the tumor.
- A 9-year-old girl with papilledema and precocious puberty is most likely to have
a. A pineal region tumor
b. An oligodendroglioma
c. A Kernohan class II astrocytoma
d. A brainstem glioma
e. An ependymoma
A
(Rowland, p 343.) The pineal region is the source of an extraordinarily diverse group of tumor types, ranging from astrocytomas (derived from glial tissue) to hemodectomas (derived from sympathetic nervous tissue). Several different types of germ cell tumors arise from the tissues in this region, presumably from embryonal cell rests. In the United States, pineal tumors account for only 1% of intracranial tumors, but one-third of these pineal tumors are germ cell tumors, including germinomas and choriocarcinomas.
- A 15-year-old boy has multiple angiomatoses of the retina and cysts of the kidney and pancreas. The brain tumor that is most likely to develop in this child is which of the following?
a. Glioblastoma multiforme
b. Meningioma
c. Hemangioblastoma
d. Ependymoma
e. Pinealoma
C
(Rowland, p 375.) With von Hippel-Lindau syndrome, the patient may exhibit tumors in multiple organs. In the brain, hemangioblastomas are the tumors most likely to arise, and these tumors are usually limited to the cerebellum or brainstem. Hemangioblastomas are often multiple and become symptomatic by bleeding into themselves. The initial episode of bleeding may prove lethal.
- A 56-year-old right-handed woman who had breast cancer 1 year ago began having neurological problems about 1 week ago. She began experiencing nausea, vomiting, and numbness in the right hand and foot. Today she is experiencing crescendo pain in the left retroorbital area. Her headache is throbbing and positional, particularly when she tries to bend forward. The headache was intense in the morning, and at times it woke her up last night. On examination, the only deficits are loss of double simultaneous tactile stimulation and right lower facial droop when smiling. The most appropriate next action would be to
a. Administer intravenous prochlorperazine
b. Give the patient a prescription for zolmitriptan
c. Make a follow-up appointment for next month
d. Order an electroencephalogram to rule out seizures
e. Get a brain MRI
E
(Victor, pp 658–660, 684–686.) The headache is typical of that caused by intracranial hypertension. Additionally, the patient has focal neurological symptoms and signs. This creates particular concern about a brain tumor or hemorrhage, and the patient should be evaluated as soon as possible. An appointment next month is too late. Intravenous prochlorperazine is a good treatment for status migrainosus; however, this history is atypical for such a diagnosis and more serious problems should be ruled out first in the emergency room. Zolmitriptan is a treatment for migraines. This history is not typical for migraine, and zolmitriptan is also relatively contraindicated in patients with complex migraine. This history is very atypical for seizures, and an electroencephalogram is not likely to provide useful information in this case.
- Further evaluation reveals multiple brain masses. The most common source of metastatic tumors to the brain is the
a. Breast
b. Lung
c. Kidney
d. Skin
e. Uterus
B
(Osborn, p 660.) The breast, lung, kidney, skin, and uterus are all common sources of metastases to the brain. The incidences of metastases from the lung and breast in women are very close, but with the climbing rates of pulmonary carcinoma in women, the lung has become the more common source. Skin lesions metastasizing to the brain include malignant melanomas.
- Metastatic lesions to the brain most often appear
a. At the gray-white junction
b. In the thalamus
c. In the posterior fossa
d. In the caudate
e. In the sella turcica
A
(Osborn, pp 660–661.) Metastatic lesions are spread primarily by the vascular system. The gray-white junction (where the white matter and the gray matter meet) is the interface at which blood-borne cells are most likely to lodge and grow. No part of the brain is exempt from the spread of metastases, but the cerebral hemispheres and the cerebellum are especially vulnerable.
- The shortest life expectancy with metastatic disease to the brain will be found in the patient with metastatic
a. Malignant melanoma
b. Breast cancer
c. Lung cancer
d. Renal cancer
e. Prostate cancer
A
(Victor, pp 697–699.) The outlook with malignant melanoma, breast cancer, lung cancer, or renal cancer metastatic to the brain is poor and limited to a matter of months, but malignant melanoma is especially grim because it is highly likely to bleed after it metastisizes to the brain. Malignant melanoma and choriocarcinoma are likely to produce lethal intracranial hemorrhages, and the former may in fact first become apparent only after it has precipitated an intracranial hemorrhage. Prostate cancer does not typically metastasize to the brain.
- A patient has a MRI performed and a colloid cyst of the third ventricle is identified. The most common complication of this lesion is
a. Bitemporal hemianopsia
b. Hydrocephalus
c. Gait ataxia
d. Optic atrophy
e. Oscillopsia
B
(Victor, pp 708–709.) Colloid cysts may produce transient or persistent obstruction of the flow of CSF. Because this is an especially deep-seated lesion, it may be more practical to simply shunt the fluid from the lateral ventricles rather than attempt to excise the cyst. These cysts are usually lined with epithelial cells and may arise from a variety of sources, including low-grade neoplasms that involute early in their evolution.
- The tumor type that is common in the brain of patients with AIDS, but otherwise extremely rare, is
a. Lymphocytic leukemia
b. Metastatic lymphoma
c. Primary lymphoma
d. Kaposi’s sarcoma
e. Lymphosarcoma
C
(Victor, pp 693–696.) Kaposi’s sarcoma is unusually common in patients with AIDS, but it is rarely metastatic to the brain. Metastatic lymphomas producing meningeal lymphomatosis are not especially rare in the general population, but primary lymphomas (that is, lymphomas apparently arising in the CNS) were rare before the AIDS epidemic. The primary brain lymphoma usually presents as a solitary mass and can occur anywhere in the brain, but it does have a predilection for the periventricular structures.
- A 37-year-old man presents with visual impairment. Examination reveals a bitemporal hemianopsia. Which of the following tumors is most likely responsible for this finding?
a. Optic glioma
b. Occipital astrocytoma
c. Brainstem glioma
d. Pituitary adenoma
e. Sphenoid wing meningioma
D
(Victor, p 714.) With bitemporal hemianopsia, the visual fields in both eyes are impaired, but only the temporal quadrants of the field in each eye are affected. Pressure on the optic chiasm inferiorly by a tumor arising in or near the sella turcica will crush the fibers crossing in the chiasm from the medial aspects of the optic nerves. The most medial fibers in both optic nerves are contributed by the nasal aspects of the retina. The nasal or medial aspects of the retina receive light from the temporal or lateral aspects of the visual field.
- A 9-year-old girl presents with precocious puberty and episodes of uncontrollable laughter. Which of the following mass lesions might explain her symptoms?
a. Craniopharyngioma
b. Choroid plexus papilloma
c. Giant aneurysm
d. Metastatic carcinoma
e. Hypothalamic hamartoma
E
(Swaiman, pp 1058–1050. Victor, pp 594–595.)
Hypothalamic hamartomas are nonneoplastic malformations involving neurons and glia in the region of the hypothalamus. They may be discovered incidentally, either on imaging performed for other reasons or at autopsy, or they may cause symptoms referable to the hypothalamus. Most often, the latter involves neuroendocrine functions, causing precocious puberty or acromegaly due to overproduction of growth hormone–releasing hormone. Patients may also experience paroxysms of laughter, known as gelastic seizures. They may be cured surgically. Craniopharyngiomas are epithelial neoplasms arising in the sellar and third ventricular regions. They may cause hypopituitarism and visual field disturbances. Choroid plexus papillomas usually develop intraventricularly and do not extend down into the sella turcica. These tumors affect both children and adults, but they are rare. They are benign if they are surgically accessible and are extirpated early in their evolution. Giant aneurysms occur in many locations, but typically do not cause gelastic seizures or precocious puberty. Metastatic carcinoma generally occurs in older patients and would not be expected to cause these symptoms.
