CD4 and lymphoma: Considering the abovementioned papers, despite the lack of a consensus, TCL is likely to be correctly diagnosed if a lymph node presents with cytology/histology suggestive of lymphoma and if (1) a prevalent population of medium-to-large lymphoid cells (≥1.3 times the size of normal T-lymphocytes) expresses uniformly CD3 and/or CD5; (2) more than 80% of total lymphoid cells have a homogeneous expression of CD4 or CD8; or (3) any aberrant phenotype in CD3 or CD5 positive cells is present, including the loss of membrane expression of CD3 in cells retaining cytoplasmic expression of CD3 only.