Autologous Hematopoietic Stem Cell Transplantation in Extranodal Natural Killer/T Cell Lymphoma: A Multinational, Multicenter, Matched Controlled Study

Abstract

Extranodal natural killer (NK)/T cell lymphoma, nasal type, is a recently recognized distinct entity and the most common type of non-B cell extranodal lymphoma in Asia. This retrospective analysis studied the potential survival benefits of hematopoeitic stem cell transplantation (HSCT) compared with a historical control group. A total of 47 patients from 3 previously published series of HSCT were matched according to NK/T cell lymphoma International Prognostic Index (NKIPI) risk groups and disease status at transplantation with 107 patients from a historical control group for analysis. After a median follow-up of 116.5 months, the median survival time was not determined for the HSCT group, but it was 43.5 months for the control group (95% confidence interval [CI] = 6.7 to 80.3 months; P = .127, log-rank test). In patients who were in complete remission (CR) at the time of HSCT or at surveillance after remission, disease-specific survival rates were significantly higher in the HSCT group compared with the control group (disease-specific 5-year survival rate, 87.3% for HSCT vs 67.8% for non-HSCT; P = .027). In contrast, in subgroup analysis on non-CR patients at the time of HSCT or non-HSCT treatment, disease-specific survival rates were not significantly prolonged in the HSCT group compared with the control group (1-year survival rate, 66.7% for HSCT vs 28.6% for non-HSCT; P = .141). The impact of HSCT on the survival of all patients was significantly retained at the multivariate level with a 2.1-fold (95% CI =1.2- to 3.7-fold) reduced risk of death (P = .006). HSCT seems to confer a survival benefit in patients who attained CR on postremission consolidation therapy. These findings suggest that, in particular, patients in CR with high NKIPI risk scores at diagnosis should receive full consideration for HSCT.

Current and future management of NK/T-cell lymphoma based on clinical trials

“…To develop a less toxic therapy than CCRT-VIPD, CISL is conducting two prospective clinical trials of modified CCRT-VIPD therapy (CCRT-VIDL [41] and CCRT-MIDLE). Notably, both prophylactic therapies for central nervous system (CNS) relapse [42] and high-dose chemotherapy with autologous hematopoietic stem cell transplantation (HD-AHSCT) [43,44] were not included in the protocol treatments in these two clinical trials of concurrent chemoradiotherapy.…”

Prognostic relevance of pretransplant Deauville score on PET-CT and presence of EBV DNA in patients who underwent autologous stem cell transplantation for ENKTL

“…Although, several studies have investigated the clinical efficacy of ASCT relative to historical controls in the settings of upfront or salvage therapy, the results have been inconclusive. 7,8,10,11,[18][19][20] Overall survival gain has been demonstrated for patients who were treated with ASCT compared to those who were treated with chemotherapy. 7,8 In particular, patients with high-risk NKPI and who attained CR demonstrated significantly improved survival after undergoing ASCT.…”

“…7,20 Published data using PET scans for patients with ENKTL are sparse, but several parameters, such as standardized uptake value (SUVmax), whole-body metabolic tumor volume, and recently, Deauville score have shown good correlation with clinical outcomes. 12,21 In the current study, we applied a Deauville score based on PET/CT to assess tumor response, because it has been reported to be feasible and reproducible, with good interobserver agreement.…”

“…However, previous studies have failed to clearly determine the efficacy of ASCT, because most of them were retrospective analyses with small sample sizes, and the enrolled patient populations were very heterogeneous, including various transplantation settings. [7][8][9][10][11] Moreover, although previous data showed that disease status at the time of ASCT was the most important prognostic factor for survival and relapse-free survival, 9,11 the optimal response assessment with respect to existing computed tomography (CT) scans, positron emission tomography/computed tomography (PET/CT) findings, and EBV DNA in blood has not yet been evaluated in ENKTL. Recently, our group suggested that post-treatment Deauville score (DS) based on PET/CT scan combined with the status of circulating EBV DNA at the end of treatment could predict the risk of treatment failure in patients with ENKTL.…”

NK/T cell non-Hodgkin lymphoma in a HIV-positive patient

“…Furthermore, as she presented with disseminated disease, radiation was thought to be most likely of little benefit. Thus, she did not receive radiation therapy despite the fact that at least some investigators think that it supplies the greatest part of treatment efficacy [16]. Although the impact of an improved CD4 count, secondary to HAART compliance, on survival is large, this patient's complete response and relatively long survival raise the possibility that NK/T cell lymphomas may be more sensitive to methotrexate-based treatment regimens than those employing anthracycline as well as implying that radiation therapy may not be as important as has been previously thought.…”