Nokea
An 8-year-old boy undergoes a resection of a tumor in the right cerebrum next to the lateral ventricle (supratentorial). The pathologist feels the histology is most consistent with an ependymoma. The tumor is sent for advanced molecular and genetic testing. Which of the following findings would further support a diagnosis of ependymoma?
- A. BRAFKIAA1549 fusion
- B. BRAFV600E mutation
- C. RELA fusion
- D. H3K27M mutation
Correct Answer: C
Rationale: The correct answer is C: RELA fusion. Ependymomas are known to have specific genetic alterations, including RELA fusions. The fusion of RELA gene is a hallmark genetic abnormality observed in certain subtypes of ependymomas, aiding in the diagnosis. Conversely, choices A, B, and D are associated with other types of brain tumors such as pilocytic astrocytoma (A), melanoma (B), and diffuse intrinsic pontine glioma (D), respectively. These genetic alterations are not characteristic of ependymomas, making them incorrect choices in this context.
You may also like to solve these questions
A 9-year-old boy is being treated for standard-risk acute lymphoblastic leukemia. His treatment protocol calls for administration of intravenous methotrexate and intramuscular L-asparaginase during interim maintenance chemotherapy. What is the most appropriate sequence of drug administration?
- A. Administer L-asparaginase during the methotrexate infusion.
- B. Administer L-asparaginase immediately after the methotrexate infusion.
- C. Administer both drugs at the same time to maximize synergistic activity.
- D. Administer methotrexate 24 hours after the asparaginase.
Correct Answer: B
Rationale: The correct answer is B: Administer L-asparaginase immediately after the methotrexate infusion. This sequence is appropriate because methotrexate can interfere with the activity of L-asparaginase if given concurrently, affecting the efficacy of both drugs. Administering L-asparaginase immediately after the methotrexate infusion allows for optimal therapeutic effects of both medications without compromising their individual actions.
Choice A (Administer L-asparaginase during the methotrexate infusion) is incorrect because it may lead to drug interactions and reduced effectiveness of both drugs. Choice C (Administer both drugs at the same time) is incorrect for the same reason as choice A. Choice D (Administer methotrexate 24 hours after the asparaginase) is incorrect as it does not follow the optimal timing for these medications during treatment.
Dohle bodies are patches of dilated endoplasmic reticulum that appear as cerulean blue cytoplasmic puddles. These findings are mostly seen in
- A. Chronic myeloid leukemia
- B. Leukemoid reaction
- C. Chediak-Higashi syndrome
- D. Infectious mononucleosis
Correct Answer: D
Rationale: The correct answer is D: Infectious mononucleosis. Dohle bodies are seen in infectious mononucleosis due to the accumulation of rough endoplasmic reticulum in neutrophils. This is a result of the viral infection causing stress on the neutrophils. In chronic myeloid leukemia (A), leukemoid reaction (B), and Chediak-Higashi syndrome (C), Dohle bodies are not typically observed. In chronic myeloid leukemia, the characteristic finding is the Philadelphia chromosome. Leukemoid reaction is a reactive increase in white blood cells due to infection or inflammation. Chediak-Higashi syndrome is a rare autosomal recessive disorder characterized by defective phagolysosome formation.
A laboratory study is conducted to determine the optimal usage of platelets for transfusion. The blood bank inventory along with the transfusion records and medical records of subjects who were recipients of platelet transfusion are reviewed. Which of the following conclusions is most likely to be made from this study?
- A. Frozen storage of platelets helps increase the units available.
- B. Platelet transfusions are rarely successful in patients with autoimmune thrombocytopenia.
- C. Platelet units carry no risk for transmission of hepatitis C infection.
- D. Pooled donor platelets are preferred over single-donor platelets.
Correct Answer: B
Rationale: The correct answer is B. Platelet transfusions are rarely successful in patients with autoimmune thrombocytopenia.
Rationale:
1. Patients with autoimmune thrombocytopenia have low platelet levels due to immune destruction.
2. Platelet transfusions may not be effective as the underlying autoimmune process continues to destroy transfused platelets.
3. Reviewing transfusion records of these patients would likely show low success rates of platelet transfusions.
Summary of Incorrect Choices:
A: Frozen storage of platelets increasing units available is not directly related to the success of platelet transfusions in autoimmune thrombocytopenia.
C: Platelet units do carry a risk of transmitting hepatitis C infection, so this conclusion is incorrect.
D: Preference for pooled donor platelets over single-donor platelets does not address the success of platelet transfusions in autoimmune thrombocytopenia.
A study is designed to investigate the rates of central line–associated blood stream infections among pediatric hematology/oncology patients. Three common central line types (totally implanted catheter [port], peripherally inserted central catheter [PICC], and tunneled externalized catheter [TEC]) were included in the study. What data structure is central line type?
- A. Continuous
- B. Dichotomous
- C. Nominal
- D. Ordinal
Correct Answer: C
Rationale: The correct answer is C: Nominal. The central line type is a categorical variable with no inherent order or ranking. Each type is distinct and cannot be quantitatively ordered or measured. It is not continuous (A), as it is not on a scale. It is not dichotomous (B) as there are more than two categories. It is not ordinal (D) because the types do not have a clear order or ranking. Therefore, central line type is best represented by a nominal data structure.
A 9-year-old boy is being treated for standard-risk acute lymphoblastic leukemia. His treatment protocol calls for administration of intravenous methotrexate and intramuscular L-asparaginase during interim maintenance chemotherapy. What is the most appropriate sequence of drug administration?
- A. Administer L-asparaginase during the methotrexate infusion.
- B. Administer L-asparaginase immediately after the methotrexate infusion.
- C. Administer both drugs at the same time to maximize synergistic activity.
- D. Administer methotrexate 24 hours after the asparaginase.
Correct Answer: B
Rationale: The correct answer is B: Administer L-asparaginase immediately after the methotrexate infusion. This is the most appropriate sequence because methotrexate can impair the activity of L-asparaginase if administered together. By waiting to administer L-asparaginase after the methotrexate infusion, the efficacy of both drugs is maximized without interference. Administering L-asparaginase during the methotrexate infusion (Choice A) would lead to decreased effectiveness of L-asparaginase. Administering both drugs at the same time (Choice C) is not recommended due to potential drug interactions. Administering methotrexate 24 hours after the asparaginase (Choice D) does not optimize the synergistic effects of the drugs during interim maintenance chemotherapy.