Unusual Relapse of Primary Central Nervous System Lymphoma at Site of Lumbar Puncture

Figure 2

Stereotactic biopsy diagnostic of diffuse large B cell lymphoma.

(a) Stereo tactic biopsy showed diffuse proliferation of large lymphoid cells with frequent mitotic figures and necrotic cells

(b) A CD20 immunostain was strongly positive in the tumor cells

(c) A ki-67 immunostain showed a proliferation index of approximately 90%