Question 134
A 35-year-old male presents to his primary care physician. Over the past 4 months he has felt a lump in his neck. Palpation reveals a painlessly enlarged lymph node. He has no past medical history and and review of systems is negative. Biopsy of the lymph node reveals occasional large binucleated cells with prominent nucleoli in a background of mixed inflammatory cells including eosinophils. The large cells are CD15 positive. Of the following markers, which is most likely to also be positive in these large cells?
A. CD5
B. CD20
C. CD30
D. CD45
E. CD103
Answer for Question 134
Answer: C (CD30)
Explanation: The histologic description is that of mixed cellularity Hodgkin disease, with the large cells being Reed-Sternberg cells. The clinical presentation of painless cervical lymphadenopathy is also consistent with Hodgkin disease. Reed-Sternberg cells are positive for CD15 and CD30, but negative for CD45 (common leukocyte antigen) as well as CD20 (B cell marker), CD5 (T cell marker) and CD103, which is found in hairy cell leukemia.
Question 135
A 56-year-old male presents to his primary care physician. Over the past 6 months, he has had frequent sweating at night, sometimes which drenches his bed clothes. Review of systems reveals occasional subjective fevers and a 15 lb. weight loss over the past several months. His past medical history includes diet-controlled diabetes mellitus and hypertension. A chest x-ray reveals enlarged mediastinal lymph nodes. A biopsy of one of the involved lymph nodes reveals scattered large binucleated cells in a background of mixed inflammatory cells. Infection with which of the following viruses is associated with the change in the lymph node?
A. CMV
B. EBV
C. HTLV
D. Hepatitis C
E. HIV
F. HSV
Answer for Question 135
Answer: B (EBV)
Explanation: The binucleated cells in a background of mixed inflammatory cells, presenting as mediastinal lymphadenopathy in a patient with B symptoms (weight loss, fever, and night sweats), is consistent with mixed cellularity Hodgkin lymphoma, which is bimodal in distribution and affects patients around 50-60 years of age. Of the viruses listed, Hodgkin lymphoma is associated with EBV.
Question 136
Over the past two days, a 12-year-old boy has had episodes of diarrhea and abdominal cramping. At first, his parents attributed it to a virus that was going around town, but then decided to take him to the emergency room when his symptoms did not improve. At CT scan of his abdomen reveals a mass at the ileocecal junction. If the mass is determined to be malignant, which of the following is the most likely diagnosis?
A. Follicular lymphoma
B. Mantle cell lymphoma
C. Extranodal marginal zone lymphoma
D. Burkitt lymphoma
E. Mycoses fungoides
Answer for Question 136
Answer: D (Burkitt lymphoma)
Explanation: In the United States, Burkitt lymphoma commonly involves the gastrointestinal tract, often at the ileocecal junction. Follicular lymphoma, mantle cell lymphoma, and extranodal marginal zone lymphoma are more frequently identified in adults and adolescents. Mycoses fungoides affects the skin.