[Recent advances and future perspectives in the treatment of NK/T-cell lymphoma].

Extranodal natural killer/T-cell lymphoma (ENKL) is a rare lymphoid malignancy that has historically poor outcomes when treated with conventional lymphoma chemotherapy regimens such as CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone). In the early 2000s, treatment strategies designed to overcome multidrug resistance were adopted. The RT-2/3DeVIC (radiotherapy, dexamethasone, etoposide, ifosfamide, carboplatin) for newly diagnosed localized ENKL and SMILE (dexamethasone, methotrexate, ifosfamide, L-asparaginase, etoposide) chemotherapy for newly diagnosed advanced-stage or relapsed/refractory ENKL, developed through clinical trials, subsequently improved the prognosis of patients with ENKL in real-world clinical practice in Japan. However, two outcome studies have also highlighted the limitations of these approaches. More recently, therapeutic development for ENKL has shifted toward PD-1/PD-L1 inhibitor-based strategies, as well as molecularly targeted therapies informed by advances in basic research. This review summarizes the current treatment landscape for ENKL in Japan, describes therapeutic developments outside Japan and ongoing investigational approaches, and discusses future directions in ENKL treatment development.