A 9-year-old boy presents to the emergency department with emesis and headache of 3 weeks' duration. MRI reveals a large heterogeneous mass in the cerebellum. He undergoes a resection, and the pathology is most consistent with a classic medulloblastoma. Which of the following findings would classify the patient as a high-risk medulloblastoma?
- A. Elevated serum and CSF AFP and beta-HCG tumor markers
- B. WNT subgrouping on molecular classification
- C. A presurgical spine MRI that reveals bulky tumor in the spine
- D. A postoperative brain MRI with no signs of residual tumor
Correct Answer: C
Rationale: The correct answer is C. A presurgical spine MRI revealing bulky tumor in the spine classifies the patient as high-risk medulloblastoma due to metastasis. This finding indicates dissemination of the tumor beyond the primary site in the cerebellum, which is associated with poorer prognosis and necessitates more aggressive treatment.
Choice A is incorrect because elevated serum and CSF tumor markers are not specific indicators of high-risk medulloblastoma. Choice B (WNT subgrouping) is associated with favorable prognosis, so it does not classify the patient as high-risk. Choice D (postoperative brain MRI showing no residual tumor) is a positive outcome but does not address the presence of metastasis, which is crucial in determining high-risk status.
You may also like to solve these questions
Platelet aggregation is an important event in hemostasis. Which of the following statement is true for platelet aggregation in vascular injury?
- A. There will be initial vasodilation
- B. Clotting factors play no role in its formation
- C. Platelets change their shape during the process
- D. Serotonin stimulates platelet aggregation
Correct Answer: C
Rationale: The correct answer is C: Platelets change their shape during the process of platelet aggregation in vascular injury. Platelets undergo shape change from a discoid to a spiky form, leading to the exposure of their glycoprotein receptors, which then bind to fibrinogen and other platelets to form a platelet plug. This process is crucial for hemostasis and preventing excessive bleeding.
Explanation for why other choices are incorrect:
A: There will be initial vasodilation - Vasodilation is not a direct result of platelet aggregation but rather an initial response to vascular injury to increase blood flow to the area.
B: Clotting factors play no role in its formation - Clotting factors are essential for the later stages of hemostasis, but platelet aggregation is primarily driven by platelet activation and shape change.
D: Serotonin stimulates platelet aggregation - While serotonin is released from platelets upon activation, it does not directly stimulate platelet aggregation.
A nurse is administering epoetin intravenously to a client who has renal failure. Which of the following actions should the nurse take?
- A. Shake the vial before using.
- B. Administer via IV bolus over 1 to 3 min.
- C. Dilute the drug first with D5W.
- D. Save the used vial for the next dose.
Correct Answer: B
Rationale: The correct answer is B: Administer via IV bolus over 1 to 3 min. This is the correct action because epoetin is typically administered intravenously over a specified time frame to prevent adverse reactions such as rapid changes in blood pressure or heart rate. Shaking the vial before using (option A) is unnecessary and may lead to frothing. Diluting the drug with D5W (option C) is not recommended for administration as an IV bolus. Saving the used vial for the next dose (option D) is incorrect and violates medication safety protocols. Administering via IV bolus over 1 to 3 min ensures safe and effective delivery of the medication.
A 5-year-old boy is evaluated for apparent ongoing hemolysis. His hemoglobin is 9.5 g/dL, with 8% reticulocytes and MCV 87 fL. Platelets and leukocytes are normal. His direct antiglobulin test (DAT) is negative. No cold agglutinin is detectable. His family history is negative for blood disorders. Peripheral smear reveals basophilic stippling in 10% of the red blood cells. Given these findings, which of the following blood disorders is most likely?
- A. Rh-null disease
- B. Hereditary pyropoikilocytosis
- C. Glucose phosphate isomerase deficiency
- D. Unstable hemoglobin
Correct Answer: E
Rationale: I'm sorry, but it seems like there might be a mistake in the question as there is no option "E" provided. Could you please provide the correct answer choice so that I can give you a step-by-step rationale for why that answer is correct?
An 8-year-old girl presents with National Cancer Institute (NCI) Standard Risk acute pre-B-cell acute lymphoblastic leukemia. Her family history is significant for her mother having been diagnosed with breast cancer at age 34 years and a maternal uncle who developed osteosarcoma as a teenager. What cytogenetic abnormality is most likely to be detected in this patient?
- A. t(1;19)
- B. CRLF2 rearrangement with a JAK2 mutation
- C. KMT24 rearrangement
- D. Hypodiploidy with a modal chromosome number of 34
Correct Answer: D
Rationale: The correct answer is D, Hypodiploidy with a modal chromosome number of 34. In pediatric pre-B-cell acute lymphoblastic leukemia, hypodiploidy with fewer than 44 chromosomes is associated with a poor prognosis. This cytogenetic abnormality is commonly seen in cases of NCI Standard Risk acute pre-B-cell ALL.
A: t(1;19) is typically associated with T-cell ALL, not pre-B-cell ALL.
B: CRLF2 rearrangement with a JAK2 mutation is more commonly seen in high-risk B-cell ALL.
C: KMT24 rearrangement is not a recognized cytogenetic abnormality in ALL.
In summary, the presence of hypodiploidy with a modal chromosome number of 34 is the most likely cytogenetic abnormality in this patient based on her clinical presentation and family history.
A nurse is caring for a client who has chronic stable angina. The nurse should identify that which of the following drugs inhibits the action of adenosine diphosphate receptors (ADP) on platelets and can be prescribed to reduce the client's risk for myocardial infarction?
- A. Clopidogrel
- B. Heparin
- C. Warfarin
- D. Alteplase
Correct Answer: A
Rationale: Clopidogrel is the correct answer because it inhibits the action of ADP receptors on platelets, reducing platelet aggregation and the risk of myocardial infarction. Heparin works by inhibiting clotting factors, Warfarin interferes with vitamin K-dependent clotting factors, and Alteplase is a thrombolytic drug that dissolves blood clots. None of these drugs target ADP receptors specifically like Clopidogrel does.