Typical and variant PB tumor cell morphology among mature T-cell leukemias. (A) T-PLL with typical prolymphocytoid morphology. (B) T-PLL with tumor cells having cerebriform nuclear morphology. (C) SS with typical cerebriform tumor morphology. (D) SS with large transformed nucleolated tumor cells (large cell, left) associated with a minor population of lower-grade tumor cells with cerebriform morphology (small cell, right). (E) T-LGL leukemia with monocytoid appearance. (F) T-LGL leukemia with high white blood cell count and variably nucleolated tumor cells. Original magnification, × 500 (Nikon Plan 50 0.5-0.85 oil lens).