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 positive, CD 5 positive, CD 23 negative, monoclonal B-cells with bright kappa positively comprising 80% of the peripheral blood lymphoid cells. The most likely diagnosis is:
Mantle cell lymphoma Splenic lymphoma with villous lymphocytes Follicular lymphoma Hairy cell leukemia