Cytology and FC of PTL. a Smear showing a relative polymorphous cell population of medium-sized lymphocytes with nuclear irregularities and coarse chromatin in a polymorphous background. Diff-Quik stain. ×430. b-e FC histograms showing: CD2/CD3 coexpression(b), CD5/CD3 coexpression(c), positivity for CD4 and negativity for CD8(d), and loss of CD8/CD7(e).