Geller S, et al. - Forty-nine cases (41 patients) with CD8+ cutaneous T-cell lymphoma (CTCL)/lymphoproliferative disorders (LPDs) were reviewed, including CD8+ mycosis fungoides (MF) (n = 14), aggressive epidermotropic CD8+ cytotoxic T-cell lymphoma (AETCL, n = 8), subcutaneous panniculitis-like T-cell lymphoma (SPTCL, n = 7), CD30+ LPD (n = 6), primary cutaneous γδ T-cell lymphoma (GDTCL, n = 6) and others (n = 8) by the researchers in order to investigate C-C chemokine receptor 4 (CCR4) expression as a diagnostic and therapeutic biomarker in CD8+ CTCL/LPDs. In 69% of the studies cases, CCR4 expression was observed. In all CD8+ MF cases, any CCR4 positivity was noted, along with, in 83%, 75%, 33%, and none of CD30+ LPD, AETCL, GDTCL and SPTCL cases, respectively. In comparison with 33% of CD30+ LPD, 17% of GDTCL, 12.5% of AETCL cases, high CCR4 expression was observed in 79% of CD8+ MF. Higher CCR4 expression was perceived in patients with more advanced MF stage. Hence, in differentiating advanced CD8+ MF from other CD8+ CTCL/LPDs, CCR4 immunohistochemistry could be an assistant. The role of such therapies in other CD8+ CTCL/LPDs was not yet apparent, while CCR4 expression may confirm the therapeutic targeting of this receptor in CD8+ MF.