Hem n Onc 8-8 (11) Flashcards Preview

Hematology and Oncology USMLE 1 > Hem n Onc 8-8 (11) > Flashcards

Flashcards in Hem n Onc 8-8 (11) Deck (30):
1

This patient presents with progressive hearing loss and tinnitus, and an MRI of the head reveals a radiopaque mass. This patient’s symptoms of progressive hearing loss and tinnitus as well as the location of her tumor indicate that she has?

bilateral vestibular schwannomas (radiopaque masses in cerebellopontine angles in the MRI). These rare benign tumors commonly arise in the vestibular portion of the eighth cranial nerve.

2

Since her tumor is bilateral, it is most likely a manifestation of an inherited condition called neurofibromatosis type 2 ((NF2). NF2 is an autosomal dominant disorder due to a mutation of the merlin gene, also called NF2, found on chromosome 22. It can predispose patients to development of multiple tumors in the nervous system.
Manifestations of NF2 can include meningiomas, ependymomas, neurofibromas, and posterior subcapsular lenticular opacities. Patients with NF2 are at heightened risk for?

developing cataracts, meningiomas, and benign eye tumors. As a result they may present with blurry or cloudy vision.

3

Bilateral vestibular schwannomas present with only sensorineural hearing loss, so this patient would not have an abnormal Rinne test, which tests solely for conductive hearing. Pigmented nodules of the iris are present in neurofibromatosis type 1, not type 2.

Nevus flammeus, also known as port wine stain, is commonly found in?

Sturge-Weber syndrome. Galactorrhea is due to increased prolactin levels, and is not a symptom of neurofibromatosis type 2.

4

The patient is presenting with a severe normocytic anemia, ptosis, and double vision. The ocular symptoms and muscular fatigue are commonly seen in patients with myasthenia gravis (MG). MG is a disorder of the neuromuscular junction, caused by ?

the autoimmune destruction of the acetylcholine receptors in the postsynaptic membrane of skeletal muscle. Symptoms of MG include diplopia, ptosis, dysphagia, weakness, and fatigue. MG is also known to be associated with thymomas. (tumors of the thymus).

5

Colon adenocarcinoma is associated with iron deficiency anemia, weight loss, bowel obstruction, colicky pain, or hematochezia.
Glioblastoma multiforme is a malignant brain tumor that is rapidly progressive and leads to death within 1 year of diagnosis in most cases. It would manifest with more neurologic symptoms, including seizures, altered mental status, and ataxia.
Lymphomas may lead to?

anemia by occupying the bone marrow and resulting in paucity of other marrow elements.
Small cell carcinomas of the lung are known for causing a variety of paraneoplastic syndromes, such as the syndrome of inappropriate ADH secretion and ectopic ACTH production.

6

This patient presents with cough, hoarseness, severe left-sided shoulder pain, droop of her left eyelid (ptosis), and constricted left pupil (miosis). The patient’s symptoms and physical exam findings are consistent with a superior sulcus tumor, otherwise known as a ?

Pancoast tumor.

Located in the apex of the lung, the mass compresses the cervical sympathetic plexus as it grows. This results in shoulder pain, Horner syndrome (ipsilateral ptosis, anhidrosis, and miosis--shown in the image), and occasionally ipsilateral neurologic deficits, such as hand weakness and hoarseness. The patient has signs and symptoms affecting the left side, so the tumor must be located in the apex of the left lung.

7

More recent data has shown that adenocarcinoma is now the most common cause of Pancoast tumors. Lung adenocarcinoma is not usually associated with paraneoplastic syndromes, and is generally found in the periphery of the lung.
Since mass invasion of cervical sympathetic plexus leads to ?

ipsilateral Horner syndrome and shoulder pain, right-sided signs and symptoms would indicate tumors at the apex of right lung. Squamous cell carcinoma of the lung would be suspected in patients with a smoking history or significant second-hand smoke exposure.

8

This patient presents with fatigue, shortness of breath, and a history of a viral upper respiratory tract infection. His physical examination reveals conjunctival pallor with slight scleral icterus and delayed capillary refill time. His laboratory test results indicate increased lactate deydrogenase (LDH), elevated bilirubin, and decreased haptoglobin. The positive direct Coombs test result and his other signs and symptoms point to a diagnosis of?

autoimmune hemolytic anemia

9

Anemia, manifesting with fatigue, jaundice, and shortness of breath, is the common thread running through the other causes listed?

Glucose-6-phosphate-dehydrogenase (G6PD) deficiency
Iron deficiency anemia
Microangiopathic hemolytic anemia (MAHA)
Paroxysmal nocturnal hemoglobinuria (PNH)

However, the result of a direct Coombs test would be negative in a patient with each of these disorders, thus ruling them out for this patient.

10

This is a 7-year-old girl presenting with cold intolerance, easy fatigability, and polyuria. She has symptoms of growth hormone deficiency (short stature), biochemically documented hypothyroidism, diabetes insipidus (polyuria), and increased intracranial pressure as suggested by bilateral papilledema (a nonspecific symptom for the patient’s condition). Imaging shows a suprasellar mass.

She likely has?

craniopharyngioma, the most common supratentorial tumor of childhood. Craniopharyngiomas account for 80% to 90% of neoplasms arising in the pituitary region. Imaging may reveal calcification within the tumor, like that shown in the images.

11

Ependymomas are most commonly found in the fourth ventricle and are tumors that can cause hydrocephalus. They rarely affect hormone levels or thyroid function.
Hemangioblastomas are associated with von Hippel-Lindau disease, retinal capillary hemangioblastomas, clear cell renal carcinoma, and pheochromocytoma.

Hemangioblastoma is not associated with?

alterations of hormone release. CT is the gold standard for diagnosis. Contrast enhanced MRI of the conus medullaris and cauda equina in a patient with vHL may demonstrate hemangioblastoma of the conus with extension into the nerve roots.

12

Like craniopharyngioma, prolactinoma also arises in the pituitary. It may manifest with symptoms similar to craniopharyngioma (such as growth hormone deficiency), but it only accounts for 2.7% of childhood tumors making it a far less likely diagnosis. In an adult patient prolactinoma would also present with signs of increased intracranial pressure, bitemporal hemianopsia, and hyperprolactinemia, which may present with amenorrhea and loss of libido.
Thyrotropinomas are very rare in childhood and do not typically suppress?

growth hormone release. This type of tumor leads to elevated T3, T4, and TSH levels and can cause similar symptoms to hyperthryoidism, including goiter, visual changes, and headache. They can be distinguished from primary hyperthyroidism by the lack of thyrotropin suppression.

13

This toddler presents with recurrent infections, abnormal facies, and a heart murmur secondary to a congenital heart defect. These findings are highly suggestive of DiGeorge syndrome, in which a deletion of 22q11 results in maldevelopment of the third and fourth pharyngeal pouches. Think CATCH-22 (Cardiac defects, Abnormal facies, Thymic hypoplasia/aplasia, Cleft lip/palate, Hypocalcemia, Chromosome 22 deletion), although most DiGeorge patients do not have all of these features.

Individuals with DiGeorge syndrome often have a ?

T-cell immunodeficiency (secondary to thymic aplasia) that renders them highly susceptible to infection. Flow cytometry of the peripheral blood for lymphocyte subsets will most likely reveal decreased numbers of T cells that are all CD3+. Not surprisingly, CD4+ helper and CD8+ effector T-cell numbers are also decreased.

14

The numbers of B cells (CD19/20) and natural killer (NK) cells (CD16/56) should be normal. Decreased B-cell counts can occur in humoral immunodeficiencies such as X-linked agammaglobulinemia and in certain variations of severe combined immunodeficiency (SCID) such as adenosine deaminase deficiency. Decreased NK cell counts can occur in ?

certain variations of SCID such as X-linked SCID and adenosine deaminase deficiency.

15

This patient is found at his well-child exam to have leukocoria in his left eye, which is an abnormal white reflection from the retina. In a patient this age, this finding is highly concerning for a retinoblastoma. Retinoblastoma occurs as a ?

result of the loss or mutation of both copies of the tumor suppressor gene Rb, which regulates the cell cycle and apoptosis.

Human papillomavirus virus (HPV) inactivates Rb through the action of the E7 viral protein. Additionally, HPV can inactivate the p53 tumor suppressor gene through the action of the E6 viral protein. HPV can thus cause cervical, anal, penile, and laryngeal cancer.

16

Although the other answer choices are associated with malignancies, they do not inactivate genes to those cause malignancies. Epstein-Barr virus (EBV, also called human herpesvirus 4 or HHV-4) is associated with Burkitt lymphoma (a B-lymphocyte lymphoma) and nasopharyngeal carcinoma. The t(8;14) translocation is associated with Burkitt’s lymphoma, but the translocation alone is not responsible for the lymphoma and is not found in nasopharyngeal carcinomas.

Hepatitis C virus (HCV) infection is associated with ?

an increased risk of hepatocellular carcinoma. The chances of oncogenic mutation increase if the liver’s regenerative process is stressed, as in cirrhosis. Immune suppression and dysregulation caused by HIV infection can give rise to lymphomas and Kaposi sarcoma.
Human T-cell lymphotropic virus (HTLV-1) is associated with adult T-cell leukemia. There is some evidence that integration of HTLV-1 into the host genome at locations near cellular growth genes may play a role in pathogenesis.

17

The patient is presenting with shortness of breath, fatigue, and dark urine, which should raise suspicion for anemia secondary to RBC destruction. This is further supported by the patient’s low hematocrit, low RBC count, and elevated indirect bilirubin. Because systemic lupus erythematosus is a part of this patient’s current medical condition, a diagnosis of?

warm autoimmune hemolytic anemia (WAIHA) is most likely.

18

Warm autoimmune hemolytic anemia can be caused by ?

SLE, CLL, or certain drugs such as α-methyldopa. The direct Coombs test is used to detect autoantibodies directed against the patient's own RBCs. “Warm” temperatures cause agglutination of IgG and “cold” temperatures cause agglutination of IgM.

19

In a direct Coombs test (depicted in the diagram), anti-human immunoglobulin (AHG, also known as Coombs reagent) is added directly to the patient's RBCs. If the patient's RBCs are coated with antibodies, the AHG will bind to those antibodies, causing agglutination, and signifying a positive result. Warm agglutinins, if present, will cause the patient's blood to agglutinate at temperatures > 37°C.
IgM autoantibodies, which are optimally active below 30°C(86°F), cause cold autoimmune hemolytic anemia (CAIHA). In CAIHA, IgM autoantibodies bind the patient’s red cells in distal body parts (like the fingertips), and then fall off in warmer body parts (like the trunk). Since IgM is a pentamer, it can attach to several different red cells, causing large red cell clumps, or agglutinates, in these colder body parts.
The indirect Coombs test, or indirect antiglobulin test, is used to detect?

the presence of unbound antibodies in the patient’s serum, which can bind to RBCs from a normal, healthy donor. The indirect Coombs test has wide application in blood transfusion serology, including antibody screening, identification, and crossmatching, but is not a useful test in the diagnosis of this patient’s condition, since it looks for serum antibodies rather than antibody-coated red cells.

20

The patient presents with episodic bouts of sweating, tachycardia, and hypertension; and a 24-hour urine vanillylmandelic acid (VMA) collection reveals an elevated VMA level. Her symptoms are consistent with pheochromocytoma, which is a rare malignancy of chromaffin cells capable of producing and releasing catecholamines, causing unpleasant symptoms. Diagnosis is usually confirmed by urinary excretion of catecholamines and their metabolites, such as VMA.

The presence of similar symptoms in the patient’s father and brother is also a clue to the diagnosis. Pheochromocytomas are associated with?

multiple endocrine neoplasia types 2A and 2B (MEN 2A and 2B). These cancer syndromes are inherited in an autosomal dominant pattern.

21

Pheochromocytoma (with symptoms including sweating, tachycardia, and hypertension) is associated with heritable multiple endocrine neoplasia (MEN) syndromes (MEN 2A and MEN 2B). MEN 2A is linked to pheochromocytoma, parathyroid cancer, and medullary thyroid cancer; MEN 2B is linked to ?

pheochromocytoma, medullary thyroid cancer, and mucosal neuromas.

22

Growth hormone adenomas, pancreatic tumors, prolactinomas, and Zollinger-Ellison syndrome are not associated with?

MEN 2A or MEN 2B syndromes. These can be found in association with the pituitary and pancreatic endocrine tumors that are typical of MEN 1.

23

The patient is presenting with several painless, purple plaques on his upper back. He is homeless, has a history of IV drug use, and is showing signs of being immunocompromised due to two recent episodes of pneumonia and oral thrush seen on physical exam. These facts should raise the suspicion for AIDS.

A biopsy of one of the lesions is performed and results show ?

spindle-shaped tumor cells. In the context of a possible HIV infection, this is diagnostic for Kaposi sarcoma, a neoplasm of endothelial cells. Kaposi sarcoma classically appears as purple plaques or nodules. Human herpesvirus 8, also known as Kaposi sarcoma-associated herpesvirus, is the oncogenic virus that infects endothelial and spindle cells, giving rise to purple lesions, as seen on the patient. Kaposi sarcoma is a considered an AIDS-defining illness.

24

Hepatitis C virus (HCV) can be transmitted through IV drug use and is associated with hepatocellular carcinoma. Porphyria cutaneous tarda is seens in some patients with HCV, but the blistering lesions of PCT are painful, not purple and painless as in this patient.

Human papillomavirus (HPV) infection is common in patients with HIV, but is not associated with Kaposi sarcoma. HPV type 16 and type 18 are associated with ?

cervical, anal, and penile carcinoma.
Human T-cell lymphoma virus type 1 (HTLV1) is associated with adult T-cell leukemia. HTLV1 can cause cutaneous skin lesions, but a biopsy would not show spindle-shaped tumor cells characteristic of Kaposi sarcoma.

Epstein-Barr virus (EBV) is associated with Burkitt lymphoma, nasopharyngeal carcinoma, and hairy leukoplakia.

25

This patient presents with persistent constriction of the right pupil and a nonproductive cough. This patient presents with persistent constriction of the right pupil and a nonproductive cough. The X-ray film reveals a lung tumor located in the right superior sulcus and lung apex (note the opacification in the area of the first rib). Cancers in this location, which are also termed Pancoast tumors, frequently strangulate and/or damage?

the second-order preganglionic sympathetic neurons that pass through the inferior cervical or stellate ganglion and ascend to eventually synapse in the superior cervical ganglion. This results in Horner syndrome: unilateral ptosis, miosis, and anhidrosis (shown in the image here).

26

Right-sided Pancoast tumors may also cause compression of the superior vena cava (SVC), causing SVC syndrome with exam findings of distended neck veins and facial/right arm swelling. Hoarseness may also be seen, due to compression of the recurrent laryngeal nerve in the neck.
Cranial nerve II involvement would cause?

visual disturbances. Cranial nerve III involvement would result in dilation of the affected pupil.First-order sympathetic involvement would occur due to a lesion at the level of the cervical spinal cord, upper thoracic spinal cord, or hypothalamus. Third-order sympathetic involvement would be implicated in injuries superior to the thoracic cavity, such as carotid dissection.

27

This patient presents with a primary brain tumor, ataxia, and elevated hematocrit. The brain tumor described in the vignette appears pathologically as foamy cells and is highly vascular (as shown in the image). These findings indicate a hemangioblastoma, a primary brain tumor found in the cerebellum in children.


A hemangioblastoma can cause?

increased levels of erythropoietin, which produces a secondary polycythemia (as signaled by this child's hematocrit at 55%). Taken together, these findings suggest von Hippel-Lindau (VHL) disease, which is associated with a defect in the VHL gene on chromosome 3.

28

Chromosome 5 is associated with familial adenomatous polyposis.
Chromosome 13 is implicated in retinoblastoma.
Chromosome 17 is linked to?

neurofibromatosis type 1.
Chromosome 22 is associated with neurofibromatosis type 2.

29

The clinical study described is a case-control study. In case-control studies, a group of participants with a disease (the cases) is compared with another group without the disease (the controls). Researchers then compare the odds of one or more exposures in the case group with those in the control group, reporting the results as odds ratios (ORs).

Based on the data provided, a 2 × 2 grid is created (see image). Of a total of 50 participants with brain cancer, 30 of them used cell phones, so 20 of them did not. Of a total of 400 participants who do not have brain cancer, 250 of them used?

cell phones, so 150 did not. In the scenario described, the OR is calculated as:
OR = (odds of using cell phones in disease group) / (odds of using cell phones in control group)
OR = (Diseased participants using cell phones/Diseased participants not using phones) / (Healthy participants using cell phones/Healthy participants not using cell phones)
OR = (30/20) / (250/150)
OR = 0.9, or 9/10

30

An OR of less 1.0 in this situation suggests that the use of cell phones decreases the odds of developing brain cancer. However, it may not be significantly different from an OR of 1.0, which indicates no association. An OR greater than 1.0 suggests that the exposure in question increases the odds of developing the disease.

Relative risk and attributable risk are metrics calculated in cohort studies. The relative risk represents the risk of patients exposed to the risk factor related to?

development of the disease compared with the patients not exposed. The attributable risk is the absolute difference in the rate of disease in an exposed population and an unexposed population. Because this scenario presents a case-control study, the answers that mention relative risk or attributable risk are incorrect. Although case-control studies can be used to report ORs, an OR of 10/9 is a calculation error in this example.