A 63-year old man presented with massive splenomegaly, lymphadenopathy and a total leucocyte count of 17000 per mm3. The flow cytometery showed CD 19 +, CD5 +, CD23 -, monoclonal B-cells with bright kappa positively comprising 80% of the peripheral blood lymphoid cells. Which of the following is the most likely diagnosis?
Mantle cell lymphoma Follicular lymphoma Hairy cell leukemia Splenic lymphoma with villous lymphocytes