Editor’s Note
Extranodal NK/T cell lymphoma (ENKTCL), nasal type, is a rare subtype prevalent in Asian populations and associated with the Epstein-Barr virus (EBV). Currently, patients’ prognosis remains poor, especially for relapsed/refractory (R/R) cases. From June 8th to 11th, 2023, the 28th European Hematology Association (EHA) Annual Congress was held in Frankfurt, Germany. A selected oral presentation (Abstract No: S226) revealed significant efficacy in treating R/R ENKTCL patients with PD-1 inhibitors alone or in combination. This study once again confirms that immune checkpoint inhibitors have become a crucial therapeutic approach for R/R ENKTCL patients. Oncology Frontier had the privilege of inviting Dr. Huang Huiqiang from Sun Yat-sen University Cancer Center, China, to share the results and insights from this research at the conference.
Oncology Frontier: EHA 2023 released research data on immunotherapy for ENKTCL. Could you share insights from this French study?
Dr. Huang Huiqiang: It is an honor to participate in the EHA Annual Congress, especially after a special three-year period. NK/T lymphoma is common in Asian populations, making us highly interested in this French study’s results. Lymphoma has entered the era of immune-targeted therapy, and this French research utilized PD-1 combined regimens for treating NK/T lymphoma. Due to the close association of NK/T lymphoma with EBV infection, there is significant immune escape in tumors, and PD-L1 overexpression is an important adverse prognostic factor. In recent years, especially at our cancer center, there have been many reports on using PD-1 inhibitors alone or in combination for treating NK/T lymphoma, accumulating valuable pioneering treatment experiences for relapsed/refractory lymphomas and gradually forming a new treatment system. However, NK/T lymphoma is less common in the West, so we are very interested in seeing research on NK/T lymphoma immunotherapy at EHA. This study included 37 patients from 24 centers in France, with long-term follow-up from 2006 to 2019. I am pleased to share the real-world treatment results from Europe with fellow professionals.
Oncology Frontier: How were the treatment results of this study, and could you provide specific details?
Dr. Huang Huiqiang: The patients included in this study all had relapsed/refractory NK/T lymphoma, treated with PD-1 or PD-1 combined with chemotherapy. The patients’ ages ranged up to 79 years old, and the overall response rate (ORR) reached 40.5%, indicating a good therapeutic effect. The 2-year progression-free survival (PFS) reached 22.4%, and the 2-year overall survival (OS) reached 50.2%. Researchers also compared the results with previous chemotherapy alone using statistical methods and found that the PFS was similar between the two groups, but the OS difference was significant (48.4% vs. 23.1%, P=0.011, Figure 1), more than doubling the long-term OS rate. Researchers believe that PD-1 inhibitors can be combined with current treatment methods, improving the overall survival of relapsed/refractory NKT lymphoma, and the toxicity is manageable. However, since this study is retrospective with a limited number of cases, researchers suggest that future prospective clinical studies incorporating PD-1 monoclonal antibodies are warranted.
Fig 1. Comparison of Survival between PD-1 Monoclonal Antibody Regimen and Chemotherapy Alone in Relapsed/Refractory NK/T Cell Lymphoma
Oncology Frontier: What profound significance does this study hold for our clinical practice, and how will we explore this treatment approach in the future?
Dr. Huang Huiqiang: Indeed, immunotherapy for NK/T cell lymphoma has just begun. Particularly for drugs like PD-1 inhibitors, the efficacy of monotherapy for NK/T cell lymphoma is often suboptimal, with some regimens having low complete response rates and short maintenance durations. Therefore, when using PD-1 for NK/T cell lymphoma, there is concern about poor efficacy or the occurrence of hyperprogression.
This study provides us with crucial information, indicating that the use of PD-1 inhibitors in combination with chemotherapy is highly effective for the general patient population. Of course, for patients with a tendency for fever or hemophagocytic lymphohistiocytosis (HLH), appropriate prophylactic measures need to be taken; after calming down inflammatory factors, using PD-1 inhibitors in combination with a regimen is safer and more effective.
Hence, such immunotherapy regimens are worth further exploration and promotion domestically. In particular, attention should be given to research on PD-1/PD-L1 inhibitor combined with lenalidomide or PD-1/PD-L1 inhibitor combined with chemotherapy as first-line treatments for NK/T cell lymphoma. Whether in the early or late stages of NK/T cell lymphoma treatment, regimens containing PD-1 inhibitors have promising clinical prospects. They are not only effective and safe but also cost-effective, bringing benefits to the majority of patients. Sufficient attention should be paid to these approaches.
▌References:
EFFICACY OF ANTI-PD1 THERAPY IN RELAPSED OR REFRACTORY EXTRANODAL NK/T CELLLYMPHOMA: A MATCHED COHORT ANALYSIS FROM THE LYSA. EHA 2023 S226.
TAG: EHA 2023, Review，Hematological Malignancy, ENKTCL
