Prognostic implications of CD30 expression in extranodal natural killer/T-cell lymphoma according to treatment modalities.

Extranodal natural killer/T-cell lymphoma (NKTCL) has aggressive behaviors and poor clinical outcomes. A monomethyl auristatin E-conjugated anti-CD30 antibody (brentuximab vedotin) was recently introduced to treat CD30-positive lymphomas. Thus we investigated the clinicopathological features and prognostic implications of CD30 expression in 72 patients with NKTCL. CD30-positive cases, defined as cases with CD30 expression in more than 1%, 5% and 25% of tumor cells as cut-off values (COVs), accounted for 40 (56%), 27 (38%) and 16 (22%) cases of NKTCL, respectively. CD30 expression was significantly higher in large/anaplastic cell-predominant NKTCL than in small/medium cell-predominant cases. CD30-positive NKTCL showed better responses to non-anthracycline-based therapy. CD30-positive NKTCL with COV of 25% showed a lower rate of relapse. Moreover, in patients treated with non-anthracycline-based chemotherapy, CD30 positivity with COV of 5% was significantly and independently associated with longer overall survival. CD30 may be useful as a prognostic factor and therapeutic target in NKTCL.