Clinicopathological analysis of primary cutaneous CD4-positive small/medium pleomorphic T-cell lymphoproliferative disorder: a retrospective study of 22 patients.

Primary cutaneous CD4-positive small/medium pleomorphic T-cell lymphoproliferative disorder is complex. Some features like folliculotropism should also be noted. Besides, the expression of follicular helper T-cell markers is not invariable. Moreover, CD8 positivity, Ki-67 index, and lesion number were perhaps not absolute prognostic indicators. To reach a diagnosis of this rare entity, putting all the pieces together is important.