1. An isolated orbital mass present for several months was found in a 55-year-old female. A surgical excision was performed, and flow cytometry showed a CD20 positive, CD5 and CD10 negative, lambda restricted lymphoid cell population. Cytogenetic showed a t(14;18)(q32;q21) translocation. Representative histologic images for this case are shown along with selected immunohistochemistry. Which of the following is the best diagnosis?

2. Several subcutaneous nodules were found in the axillary region of a 59-year-old male. Representative histologic images and special stains are shown. Based on these findings, which of the following is the best diagnosis?

3. Examination of a lymph node shows extensive infiltration by macrophages with foamy cytoplasm. Staining with PAS, shows diastase resistant material. AFB stain is negative. Which of the following answers would be the best diagnosis:

4. Which of the following leukemias is least commonly associated with abnormalities involving chromosome 11q23?

5. B-cell prolymphocytic leukemia is characterized by which of the following?

6. An absolute leukocytosis was identified in a 71-year-old African-American male admitted to the hospital for an elective knee replacement. Based on the flow cytometry findings, what is the best diagnosis?

7. An osmotic fragility test was performed on the blood specimen from a 45-year-old patient who has a microcytic anemia (MCV = 73, RBC = 3.8 x 10^6 /mL, Hb = 11.0 g/dL, & Hct. = 33.4%). Based on these laboratory values and the findings on the osmotic fragility test, what is the most likely diagnosis?

8. A splenectomy was performed in a three-year-old female. The spleen is approximately twice the normal size when adjusted for age. Based on the histologic findings shown for this case, which the following is the best diagnosis?

9. A submandibular mass has been noted for several months in a 40-year-old female patient. A FNA was performed with flow cytometry, which was negative for a monoclonal lymphoid population. A surgical excision of the lesion was performed and submitted in formalin. Representative histologic sections are shown along with immunohistochemistry. Based on the findings and clinical history, which of the following is the best diagnosis?