A 58-year-old man complains of weakness and tumor-like formations that appeared on the anterior surface of his neck and in the inguinal region. Palpation detects soft painless mobile cervical and inguinal lymph nodes up to 2 cm in diameter. The liver protrudes by 2 cm from the edge of the costal margin, the lower splenic pole is at the umbilical level. In blood: erythrocytes - 3.5 × 1012/L, Hb- 88 g/L, leucocytes - 86 × 109/L, band neutrophils - 1%, segmented neutrophils - 10%, lymphocytes - 85%, eosinophils - 2%, basophils - 0%, monocytes - 2%, erythrocyte sedimentation rate - 15 ram/hour, Gumprecht shadows. What is the most likely diagnosis?