What is the most likely diagnosis?

C. Peripheral blood smear reveals that the majority of peripheral blood lymphocytes are larger in size than their normal counterparts, with ample amount of cytoplasm lacking granulation and prominent nucleoli. This finding and the immunophenotype are characteristic of B-PLL. B-PLL is a de novo leukemia in which prolymphocytes comprise 55% or more of the blood lymphocytes. Massive splenomegaly and systemic B symptoms are common presenting manifestations in patients with B-PLL. Flow cytometry reveals lack of T-cell markers and lack of CDS and CD23 expression. Lack of CDS and CD23 expression is not consistent with classical CLL, while the lack of CDS expression argues against the diagnosis of MCL. Absence of T-cell markers and cytoplasmic granulation does not sup-port the diagnosis of T-LGL or T-PLL. Cases of B-PLL are characterized by strong expression of sur-face IgM. There is no standard regimen for the treatment of B-PLL; however, fludarabine, rituximab, and alemtuzumab in addition to classical combination chemotherapy regimens have been used with variable success (Hematol Oneal Clin North Am. 1990;4(2):457, Hematol f. 2004;5 Suppl 1 :550, Leuk Lymphoma. 2002;43(5):1007, Am J Hematol. 2007;82(5):417, Ann Hematol. 2004;83(5)3 19, Blood. 2012;120(3):538, Leuk Lymphoma. 1999;33(1 -2):169).