Hematology & Oncology Practice Questions

A 68-year-old man presents for a routine physical examination. He reports no specific complaints, but a complete blood count reveals a white blood cell count of 80,000/microL with 75% lymphocytes. Peripheral blood smear shows numerous 'smudge cells.' Flow cytometry of the peripheral blood demonstrates lymphocytes that co-express CD5 and CD20. This patient's condition arises from the neoplastic proliferation of which of the following cell types?

A 10-year-old girl is brought to the pediatrician due to a history of recurrent epistaxis, easy bruising, and prolonged bleeding after minor cuts and dental procedures. Her mother reports having similar issues. Laboratory tests show a normal prothrombin time (PT), a prolonged activated partial thromboplastin time (aPTT), a prolonged bleeding time, and a normal platelet count. Which of the following is the most likely diagnosis?

An 8-year-old boy with a known history of sickle cell disease is brought to the emergency department by his parents due to a sudden onset of fever, cough, and chest pain. His temperature is 39.0°C (102.2°F), respiratory rate is 30 breaths/min, and oxygen saturation is 90% on room air. Auscultation of the lungs reveals crackles at the right lung base. A chest X-ray shows new pulmonary infiltrates in the right lower lobe. Which of the following is the most likely acute complication?