Question 1

All of the following are included in the chronic myeloproliferative disorders except:

Accepted Answer

Acute myeloid leukemia is not included in the chronic myeloproliferative disorders as it is classified as a separate type of leukemia. The chronic myeloproliferative disorders include chronic myelogenous leukemia, polycythemia vera, essential thrombocythemia, and primary myelofibrosis.

Question 2

Which of the following would be an unexpected finding in chronic myelogenous leukemia?

Accepted Answer

In chronic myelogenous leukemia (CML), finding 20% blasts in the peripheral blood would be unexpected as it suggests a progression to a more acute phase of the disease, such as blast crisis, rather than the chronic phase which typically features less than 10% blasts.

Question 3

A patient has an increased red count, hemoglobin, and hematocrit. Which of the following features points to secondary polycythemia over polycythemia vera?

Accepted Answer

One of the main causes of secondary polycythemia is chronic hypoxia, which stimulates the production of erythropoietin (EPO) and leads to an increase in red blood cell production. As a result, patients with secondary polycythemia often have decreased arterial oxygen saturation. In contrast, polycythemia vera (a primary myeloproliferative disorder) typically presents with an increased red cell mass and bone marrow erythroid hyperplasia, but not necessarily with decreased arterial oxygen saturation. Increased white count may or may not be present in either condition.

Question 4

A high red count, hemoglobin, and hematocrit are found in all of the following except:

Accepted Answer

Bone marrow aplasia (also known as aplastic anemia) is characterized by a decrease in all blood cell types due to a failure of the bone marrow to produce enough new cells. This would result in a low red count, hemoglobin, and hematocrit. The other options listed all involve an increase in red blood cells and would exhibit high red count, hemoglobin, and hematocrit readings.

Question 5

Which of the following is true for the mutated erythroid progenitors in polycythemia vera?

Accepted Answer

Mutated erythroid progenitors in polycythemia vera are more resistant to apoptosis than normal erythroid progenitors, which leads to the excessive production of red blood cells. A is incorrect because the mutated progenitors actually require less erythropoietin for growth. C is incorrect because poikilocytosis (abnormal shape of red blood cells) is not a characteristic feature of polycythemia vera. D is incorrect because the Philadelphia chromosome, a translocation between chromosomes 9 and 22, is associated with chronic myeloid leukemia, not polycythemia vera.

Question 6

Which of the following is true for chronic myelogenous leukemia?

Accepted Answer

Chronic myelogenous leukemia is a clonal process arising from the pluripotent stem cell.

Question 7

Bone marrow or stem cell transplantation is the therapy of choice for patients younger than 55 years old with:

Accepted Answer

Bone marrow or stem cell transplantation is the therapy of choice for younger patients with chronic myelogenous leukemia. It is not typically used for essential thrombocytosis or polycythemia vera unless the patient has progressed to acute leukemia or myelofibrosis.

Question 8

Chronic myelogenous leukemia often progresses to:

Accepted Answer

Chronic myelogenous leukemia can transform into an acute leukemia, either myeloid or lymphoblastic, in a process called blast crisis. This is often the final and most aggressive phase of the disease, with a poor prognosis. The other options are not common progression paths for chronic myelogenous leukemia.

Question 9

A patient has a normal white blood count, a moderately high platelet count, and mild anemia. The differential shows immature granulocytes, nucleated red cells, and teardrop-shaped red cells. Which of the following is most likely?

Accepted Answer

The combination of immature granulocytes, nucleated red cells, and teardrop-shaped red cells suggests a myeloproliferative disorder with bone marrow fibrosis, which is characteristic of primary myelofibrosis. Polycythemia vera would typically show elevated red cell counts, while chronic myelogenous leukemia would show elevated white cell counts with immature myeloid cells. Essential thrombocythemia would show primarily elevated platelet counts, without the presence of immature granulocytes or nucleated red cells.

Question 10

The Janus kinase (JAK) mutation is seen in more than 90% of cases of what disease?

Accepted Answer

The Janus kinase 2 (JAK2) mutation is most commonly associated with polycythemia vera, where it is present in over 90% of cases.

Question 11

Which of the following is an expected finding in polycythemia vera?

Accepted Answer

Polycythemia vera is characterized by an increased production of red blood cells, as well as elevated platelet and white blood cell counts. Thrombocytosis is a commonly seen finding in polycythemia vera, while anemia is not. Low leukocyte alkaline phosphatase and normal white count are not specific findings for this condition.

Question 12

Which of the following would be an unexpected finding in primary myelofibrosis?

Accepted Answer

Primary myelofibrosis is a chronic myeloproliferative neoplasm characterized by bone marrow fibrosis and abnormal blood cell production. The presence of 80% blasts in the peripheral blood would be an unexpected finding since blast transformation is not typically associated with primary myelofibrosis. Micromegakaryocytes in the peripheral blood and extramedullary hematopoiesis are expected findings. Autoantibodies may be present in some cases but are not a defining feature of primary myelofibrosis.

Question 13

The bone marrow fibrosis observed in primary myelofibrosis is due to:

Accepted Answer

The bone marrow fibrosis seen in primary myelofibrosis is primarily due to the increased release of fibroblastic growth factors, such as platelet-derived growth factor, by the clonal megakaryocytes and platelets in the marrow. This leads to the proliferation of fibroblasts and subsequent fibrosis.

Question 14

What do all chronic myeloproliferative disorders share?

Accepted Answer

Chronic myeloproliferative disorders all involve an overproduction of blood cells, and the clinical and laboratory features can overlap between them. The Philadelphia chromosome is only present in chronic myeloid leukemia, and increased red cell mass is specific to polycythemia vera. Serious thromboembolic complications can occur in any of these disorders but are not a unifying feature.

Question 15

Although found in most chronic myeloproliferative disorders, increased fibrosis detected by the silver techniques and trichrome stain is the key feature of:

Accepted Answer

Increased fibrosis detected by silver techniques and trichrome stain is the key feature of primary myelofibrosis, also known as idiopathic myelofibrosis. The other chronic myeloproliferative disorders may have some degree of fibrosis, but it is not the primary feature. In secondary polycythemia, there is an increase in red blood cell production due to conditions such as hypoxia or EPO-producing tumors. Chronic myelogenous leukemia is characterized by the Philadelphia chromosome and increased granulocytes. Essential thrombocythemia is characterized by increased platelets.

Question 16

Which of the following is the most specific laboratory test to diagnose chronic myelogenous leukemia?

Accepted Answer

Leukocyte alkaline phosphatase (LAP) is a specific laboratory test that can help diagnose chronic myelogenous leukemia (CML). In CML, LAP activity is reduced or absent in neutrophils, which distinguishes it from other leukemias where LAP activity is normal or increased. Increased bone marrow fibrosis and reticulin fibers, increased eosinophils and basophils, and blasts in the bone marrow are non-specific findings that can be seen in other types of leukemias or myeloproliferative disorders.

Question 17

The Philadelphia chromosome:

Accepted Answer

The Philadelphia chromosome results from a reciprocal translocation between chromosomes 9 and 22, which creates a chimeric gene called bcr/abl. This gene produces a tyrosine kinase that leads to uncontrolled cell growth and is responsible for the development of chronic myelogenous leukemia.

Question 18

What clinical feature is more often associated with essential thrombocytosis than with the other chronic myeloproliferative disorders?

Accepted Answer

Essential thrombocytosis is more commonly associated with bleeding and thrombosis compared to the other chronic myeloproliferative disorders such as polycythemia vera and myelofibrosis. Splenomegaly is more commonly seen in myelofibrosis, while fatigue and infections can be observed in all three disorders.

Question 19

A patient has a platelet count of 1200 *10⁹/L. Many platelets are giant and have abnormal shapes. A mild anemia is present. The bone marrow has increased megakaryocytes in clusters; iron stores are present. Which of the following is most likely?

Accepted Answer

The platelet count is significantly elevated and the bone marrow shows increased megakaryocytes in clusters, which is consistent with essential thrombocythemia. The presence of giant and abnormal-shaped platelets and mild anemia also supports this diagnosis. Chronic myelogenous leukemia typically presents with increased white blood cell count and the presence of the Philadelphia chromosome. Thrombocytosis secondary to blood loss would not cause such a significant elevation in platelet count, and polycythemia vera would present with increased red blood cell count and hematocrit.

Question 20

Which chronic myeloproliferative disorder is treated with Imatinib mesylate (Gleevec), a drug that inhibits tyrosine kinase?

Accepted Answer

Imatinib mesylate (Gleevec) is a drug that specifically inhibits the tyrosine kinase activity of the BCR-ABL fusion protein, which is present in most cases of chronic myelogenous leukemia (CML). Therefore, it is a targeted therapy for the treatment of CML. It is not used to treat polycythemia vera, essential thrombocythemia, or primary myelofibrosis.

Quiz 34: Myeloproliferative Neoplasms

All of the following are included in the chronic myeloproliferative disorders except:

Which of the following would be an unexpected finding in chronic myelogenous leukemia?

A patient has an increased red count, hemoglobin, and hematocrit. Which of the following features points to secondary polycythemia over polycythemia vera?

A high red count, hemoglobin, and hematocrit are found in all of the following except:

Which of the following is true for the mutated erythroid progenitors in polycythemia vera?

Which of the following is true for chronic myelogenous leukemia?

Bone marrow or stem cell transplantation is the therapy of choice for patients younger than 55 years old with:

Chronic myelogenous leukemia often progresses to:

A patient has a normal white blood count, a moderately high platelet count, and mild anemia. The differential shows immature granulocytes, nucleated red cells, and teardrop-shaped red cells. Which of the following is most likely?

The Janus kinase (JAK) mutation is seen in more than 90% of cases of what disease?

Which of the following is an expected finding in polycythemia vera?

Which of the following would be an unexpected finding in primary myelofibrosis?

The bone marrow fibrosis observed in primary myelofibrosis is due to:

What do all chronic myeloproliferative disorders share?

Although found in most chronic myeloproliferative disorders, increased fibrosis detected by the silver techniques and trichrome stain is the key feature of:

Which of the following is the most specific laboratory test to diagnose chronic myelogenous leukemia?

The Philadelphia chromosome:

What clinical feature is more often associated with essential thrombocytosis than with the other chronic myeloproliferative disorders?

A patient has a platelet count of 1200 *10⁹/L. Many platelets are giant and have abnormal shapes. A mild anemia is present. The bone marrow has increased megakaryocytes in clusters; iron stores are present. Which of the following is most likely?

Which chronic myeloproliferative disorder is treated with Imatinib mesylate (Gleevec) , a drug that inhibits tyrosine kinase?

Quiz 34: Myeloproliferative Neoplasms

All of the following are included in the chronic myeloproliferative disorders except:

Which of the following would be an unexpected finding in chronic myelogenous leukemia?

A patient has an increased red count, hemoglobin, and hematocrit. Which of the following features points to secondary polycythemia over polycythemia vera?

A high red count, hemoglobin, and hematocrit are found in all of the following except:

Which of the following is true for the mutated erythroid progenitors in polycythemia vera?

Which of the following is true for chronic myelogenous leukemia?

Bone marrow or stem cell transplantation is the therapy of choice for patients younger than 55 years old with:

Chronic myelogenous leukemia often progresses to:

A patient has a normal white blood count, a moderately high platelet count, and mild anemia. The differential shows immature granulocytes, nucleated red cells, and teardrop-shaped red cells. Which of the following is most likely?

The Janus kinase (JAK) mutation is seen in more than 90% of cases of what disease?

Which of the following is an expected finding in polycythemia vera?

Which of the following would be an unexpected finding in primary myelofibrosis?

The bone marrow fibrosis observed in primary myelofibrosis is due to:

What do all chronic myeloproliferative disorders share?

Although found in most chronic myeloproliferative disorders, increased fibrosis detected by the silver techniques and trichrome stain is the key feature of:

Which of the following is the most specific laboratory test to diagnose chronic myelogenous leukemia?

The Philadelphia chromosome:

What clinical feature is more often associated with essential thrombocytosis than with the other chronic myeloproliferative disorders?

A patient has a platelet count of 1200 *109/L. Many platelets are giant and have abnormal shapes. A mild anemia is present. The bone marrow has increased megakaryocytes in clusters; iron stores are present. Which of the following is most likely?

Which chronic myeloproliferative disorder is treated with Imatinib mesylate (Gleevec) , a drug that inhibits tyrosine kinase?

A patient has a platelet count of 1200 *10⁹/L. Many platelets are giant and have abnormal shapes. A mild anemia is present. The bone marrow has increased megakaryocytes in clusters; iron stores are present. Which of the following is most likely?